When was the last time it was cycled?
During storage when not cycling do you keep it refrigerated?
Is it covered while it's stored or fermenting?
Provided you've got a proven sourdough formula, you've followed it correctly,
and you've maintain the fermentation parameters, it should be alright if you
break the top surface by opening it to expose the fresh dough under it. Use the
fresh dough and discard the outer moulded crust. Although? Mould can sometimes
be a sign of poor lactobacillus activity.
If I make a spontaneous sourdough, I no longer use flour to culture the
desirable microflora. I find the results more variable and requiring more
cycles to achieve the desired microflora in the ascendency. I now use fruit skins
for the initial culture period.
Jeremy, could well be right, and you may save yourself time to start from scratch. However, you could try it for three or five cycles using the fresh dough under the crust that's not mould infected. I'm
willing to bet it'll be ok if you keep it refrigerated but cycle it regularly
ensuring you keep to the schedule parameters.
at the prospect of making your own bread, there's a primeval resonance, a bit like hunting or growing your food.I've been baking for almost 30 years but I still get excited when I see great bread. Keep us informed of your progress, it'd be nice to see the fruits of your labour.
i remember reading that many types of mould are toxic and you should not eat anything with mould on it.
not sure what happens with mould during baking, maybe it becomes harmless?
if it was me i would make sure to refresh for few days and watch if it comes back.
Croc, moulds and other bacterial groups are also present in healthy sourdoughs but their population numbers are kept in check by Lactobacullus presence and the by-products it produces. If the sourdough is allowed to degenerate by careless hygiene or disregarding fermentation parameters, especially in the early stages other groups can move into the ascendency. Moulds are often the first to appear. However, moulds are also a sign of reduced Lactobacullus numbers and/or activity. Della's starter is still imature, especially if flour was the only original substrate.
I did mention that to begin a spontaneous sourdough I now use fruit as the original substrate to culture the desirable bacteria and yeasts and only after seven days do I introduce the liquid from this into a dough. I have had better results using this method comapred to using flour.
Actually when I started the culture I use now I had mould issues as well. I started using fruit(organic grapes) as the original substrate and it got off to a bubbly start in a few days which I then poured into my dough mixture. But after the 2nd or 3rd feeding (I think) there was mould on the little bits of semi-dried dough that I didn't mix in properly with the rest of the mass. I think it was probably me being careless since by not keeping the sides of the container clean I left bits of dough (really small particles actually, but still) that didnt get to be fermented with the rest of the lot, other organisms kinda colonized it. I suppose cleaning the bits up with a wet paper towel would have probably made a difference.
But I just spooned out some of the good starter into a cleaner container and fed it again and it's been fine since. Lucky me!
Yesterday, I got the starter out of the fridge at work which has been idle for 10 weeks. Of course, to the uninitiated it looked beyond redemption. It was slightly mouldy and had a surface aroma with a Camembert backnote. The other bakers not familiar with sourdough were horrified that I was going to use it to start a sourdough. When I broke open the crust to reveal a bright paste underneath their fears were somewhat allayed.
However, I weighed up the flour, water, and the clean starter from under the discoloured mouldy crust in the desired proportions and mixed it for the desired time. Allowed it to ferment 15hrs; the fermentation was strong, aromatic, and the sourdough exhibited all the characteristics it should. Today I used the whole sourdough to again start a larger sourdough that will be used next week to make a variety of bread.
The missed opportunity lies in the fact that I didn't photograph it in its idle mouldy state and then in its recycled state for you to see it.
Anyway, I'll photograph the bread later next week and post it here so you can see that healthy sourdoughs are more robust than most imagine.
What about an acidic sourdough that sits in the fridge, is that spawn of satan?(John Downes gave it that moniker!) What should home bakers do with sour, keep it out and keep feeding daily, weekly? Or can some be stored in the fridge?
[quote=Jeremy]What about an acidic
sourdough that sits in the fridge, is that spawn of satan?(John Downes gave it
that moniker!)
What should home bakers do with sour, keep it out and keep feeding daily,
weekly? Or can some be stored in the fridge?
[/quote]
G'day Jeremy, "acidic sourdough"? Am I correct to assume you're
referring to a sourdough that is over mature and has an acetate aroma? (Akin to
'butyl acetate' a bit like nail polish remover) Is this what you're referring
to?
In the case I outlined in the previous post where the starter sat idle for 10
weeks the starter was actually a mature sourdough that was refrigerated
immediately after the conclusion of the specified fermentation time. This means
that it was at its peak in viable microbe numbers and the fermentation had not
continued to form significant quantities of more exotic by-products such as
acetates and lactylates. This was done precisely because it was to be stored
for an extended period. In our case we were leaving for summer holidays and
were not to return until the beginning of February. My reason for posting this
example was to show Della that once a healthy sourdough is achieved it should
continue to remain relatively viable even if moulds appear on the surface.
In the case of home bakers I'd suggest keep baking and refreshing your
sourdoughs regularly. The more often the sourdough is cycled within tried and
tested parameters the better its resilience. I would also use the refrigerator
when the sourdough is outside the specified fermentation time. The reason for
this is to retard the production of fermentation by-products. I've seen home
bakers mystified by the variation they find in their bread from one day to the
other in spite of insisting they did..."everything the same" and upon
questioning it becomes clear their sourdough maturity has varied due to lack of
consistent fermentation times. The fridge can mitigate extended fermentation
times by simple temperature control.
However, John's advice to Ruth - [url=http://sourdough.com.au/?q=forum/topic/1103#comment-8347][b]see
here[/b][/url] - makes plenty of sense. For commercial bakers consistency is
critical but for home bakers there plenty of acceptable latitude. Besides, its
better for it to be an enjoyable experience and not a source of anxiety or
pressure. Sometimes I just don't feel like baking, so I don't. It gives me a
chance to grab some bread from one of the sourdough bakeries and try something
new.
I hope I've answered your question without being tedious.
I too can attest to your statement with success. I too left my starter in the refrigerator, but it was for only 3 weeks. When I came back, there was "hooch" on the top of the starter but no mold that I could detect. I discarded the liquid and proceeded to feed my over starved starter. After about 4 days of feeding, my starter was back to life.
Ok, I had no idea it was called hooch. Do you know the origins of the word "hooch" in this context?
If I find my sourdough that has been sitting for a while and develops hooch, I use the paste, much like you, TP, from under the liquid or crust to cycle it. I have never used it directly into a bread dough.
The rye is from Weston milling and is a very low extraction rye - endosperm only - I've contacted them for a report which will among other things have the ash content. The bakers flour will have .550 ash content.
The young apprentice who made those loaves was very proud of the results. Thanks for the compliments.
Do you think sourdough should have a Rheinheitsgebot (purity code or law?) and who would administer those rules?
[/quote]
Jeremy, I'm not too keen on 'administers' of anything, for good reasons, but I can see the need to have clear definitions. In the past the Trade Guilds were the custodians of these matters.
Of course i do Jeremy, but..."as if"...even the Germans are now allowing sugar in beer!!! It would be good because it sperates wheat from chaff,ie,the consumer knows what they are getting,and that has two aspects.
Firstly,ive got a right to know that i am getting what i pay for, its contractual law actually. At present one can purchase a "sourdough" completely made with yeast and having no sourdough microbiology at all, they are everywhere. Thats a fraud,but we have bakers, writers and educators who dont know or care, or think that sourdough is just a name to be exploited.So from the point of our culinary culture,it means everything is just a mush (mutton is lamb and honey is sugar), and consumers are fair game.
On a more serious note,it is documented that genuine sourdough bread is therapeutic,notably with type 2 diabetes. A diabetic who is aware or this and seeks remission through dietary means,using s/d, will not get that benefit, and thats a clinical fraud really.
Also,as an Artisan making genuine sourdough bread,my trade is reduced by unfair competition from those who fake their sourdoughs. Im not sure,but i reckon this actually breaches the Trade Practices Act. I sell less because there are analogs out there. This is not allowed in other trades.
The big problem is that there are no Trade standards,and frankly i dont think the trade cares.Consumers do,and are becoming more informed than the bakers themselves.
But as far as what i was saying about the fruit ferments which Danubian is doing,well thats just good news really,and as we have the pleasure of enjoying Pils or lager or ale, or shiraz ,sangiovese or nebbiolo, it enriches our enjoyment of proper food, and is a plus for the trade.
Its just a shame all of this gets lost ,unlike in the wine or cheese industry which promote authenticity and diversity, because the bakery trade is frankly,braindead.
I wonder or assume that it is because of agribusiness taking over farms and encouraging crops for there market, without really benefiting either the land or the whole spectrum of what is in our diet? (Did I make sense?) Even beer one of my favored fermented beverages has been neutered, watered down, and dare I say it, taken over by the largest multinationals! Thank goodness for small underground food culture, but even there craft is hodge-podge I think? My own humble opinion. And what about craft guilds, are those also too restraining in terms of individual efforts, what your opinion? Should do another interview, got to get the other edited still, bloody hell!
[quote=JohnD]Its just a shame all of this gets lost ,unlike in the wine or cheese industry which promote authenticity and diversity, because the bakery trade is frankly,braindead.[/quote]
I have to agree with most of your post. However, not all are "braindead", you - although you may not consider yourself part of the "Baking Industry" you are! - and I are examples of enlightened bakers. There are many others and our ranks are swelling by the day.
Im part of the industry yep, and i wasnt saying the "Industry" is braindead,but the "trade" i said shows signs of it....bread missed out on the niches wine and cheese have established through good marketing and vision, because of the torpor of the bread trade....that is the purveyors of bread, who seem content with the LCD. Agreed, this is changing, but only as a reaction to what was initiated outside the "trade". The big challenge for the trade,is to not fake it, and deliver the goods for the public.
Just wanted to ask John about barm, we touched on it a bit and I was reading a thread on Dan Lepards site where he defines it as pregelatinized starch from grain...let me get the thread up and make sure I am not blaspheming or not correctly quote verbatim! http://www.danlepard.com/forum/viewtopic.php?t=117&postdays=0&postorder=...
lepard Site Admin
Joined: 15 Jun 2003 Posts: 1212
Posted: Tue Dec 07, 2004 9:35 am Post subject:
To start with, a little definition of a barm, from 'The Bakers ABC', by John Kirkland (Gresham Publishing, London, 1927)
Barm - An old word, the name for the thick froth produced in brewers'
vats, and sold for breadmaking purposes, and for brewing of home-brewed
ales, ginger beer, and treacle beers.
In the trial of the Earl of Somerset for high treason and for the
murder of Sir Thomas Overbury, in the reign of James I, the arraigning
counsel, Sir Francis Bacon, mentions barm, or yeast, as an agent for
poisoning.
"As we may see in the example of Henry VIII, that where the purpose was
to poison one man, there was poison put into barm or yeast; and with
the barm, pottage or gruel was made, whereby sixteen of the Bishop of
Rochester's servants were poisoned."
Thus the word barm, with a precise if sinister meaning and
association, was in use over three hundred years ago. The term is still
used in country districts as meaning brewer's yeast, and in some parts
is even applied to pressed yeast.
But since bakers, or others for them, began to make a fermenting
agent for themselves, about 1800, that has been described as barm,
while the word yeast has been retained for the brewery product, as well
as for the more modern article sold in solid form.
Barm contains yeast cells, generally of a variety of species, as well
as some of the liquor in which the yeast has been grown. Barms are of
many kinds, and of all degrees of "strength"; that is, a particular lot
may contain few or many yeast cells, and much or little of the acids,
peptones, alcohols, &c., which have resulted from previous
fermentations.
Probably the earliest barm made, as distinguished from leavens, was
that from malt and hops, as the baker in the first instance merely
copied the brewer or the distiller. This barm was known as "compound",
or "comp", or "patent". Some makers used a quantity of flour in the
mixture, some did not.
In Scotland, where barms were first made, and where they still
continue in favour, the compound barm was displaced by a kind made with
scalded flour and malt. To this was given the name of " Parisian ",
although there is no precise evidence to show that it was copied from
the practice of Parisian bakers. Another sort which may contain a
little malt, but may be all scalded and raw flour, is called " Virgin
Barm ".
A kind much used in Australia, South Africa, &c., has boiled
potatoes, sugar, baked flour, and bran as the constituents of the mash.
This is called " spontaneous", or "spon", probably because, in the
regions in which it is used, the liquid will start fermenting without a
"stock" of old barm, and mature sufficiently to be used for
breadmaking, by a straight dough process, under such conditions in
about 30 hours.
Barms have, of course, to be used in comparatively large quantity.
It is a strong barm that contains 12 oz. of yeast to the gallon, and
the work is done by the yeast cells only. Barms have much influence on
the nature of the bread. Flour barms produce a condition of crumb that
might be described as raw: it seems moist and slightly clinging, but
the bread is white and its skin smooth.
As a rule, except in the case of "spontaneous " referred to above,
barms are used with a long process of fermentation, either in two or
three stages, and the flavours attributed to the barm may be due really
to the changes in material within the dough, resulting from the
processes.
Quote:
Why heat the beer?
To drive off the alcohol and to gelatinize the starch. For a little
more detail about the changes that occur, here is a passage from
William Jago's classic late 19th century treatise, 'The Science and Art
of Breadmaking' (Simpkin, Marshall, Hamilton, Kent & Co., London,
1895)
'The barm tub and contents are left in the brew-house uncovered for
21 hours or so. During that time the mixture, undergoes several
changes. The scalding water bursts a proportion of the starch granules
of the flour, converting them into starch paste: the diastase of the
malt inverts or hydrates this paste into a sugar, maltose, and a brown,
gummy body, dextrin. The mixture, after scalding, tastes very sweet; in
half an hour after it is sweeter, and thinner, and browner. These
changes continue for several hours, then a distinct acid taste is
felt.'
Quote:
What is the effect of combining the yeast in the beer with the yeast in the starter?
Simply to add complexity to the flavour of the barm.
Quote:
Do you maintain a barm in the same way as a starter or do you make up a new one each time?
You would have made a new one at the end of the week, otherwise the
ferment becomes sour. And sourness wasn't an intention of bakers, but
rather something to avoid as it stopped bread selling - we didn't have
a big tradition of sour flavours in the British diet, even our pickles
are sweet.
But… now we do. However, if you were to simply refresh the barm
with flour and water the result would eventually be no different to a
leaven. So I would remake the barm from scratch in order to keep a
hoppy taste to the loaf.
For a much sharper and brighter taste to the loaf, omit the water
from the final dough and decrease the flour and salt accordingly (to
your preference, and chosen crumb structure)
I'll say it once again. A
starter or leaven made from beer yeast, flour and water is just that. A
barm, however, as known by bakers working up until the introduction of
compressed German yeast, is a gelatinized mixture of mashed malted
grains, hops and flour. As the traditional recipe is very
complicated and involves mashing malted grains and boiling hops, I have
written a recipe that takes live beer and attempts to take it back a
stage prior to fermentation creating alcohol, by heating the mixture
both to gelatinize the flour and to try and return beer to its state
before fermentation commenced.
Is there a difference between a barm and a starter made from a live beer?
Yes. A 'starter made from live beer' is a starter made from live
beer. A barm is a gelatinized mixture of mashed malted grains, hops and
flour.
Could you touch on this topic a bit and it's role within sourdough?
I have a different view. A Parisian barm only,is made with the boiling water used to gelatinise the starch in flour, and malt is added,according to sources ive read,and this is attested by the fact that this barm is called "Parisian",which means it is distinguised from a "regular" barm, usually grown on a wort of malted grains, seeded from a "stock".
But to be definitive about a historical term is fraught,especially as it is source dependant and there are few sources, and these cannot be seen as covering the whole gamut of usage. We are not talking scientific taxonomy here,but very fluid colloquial language. The bit about the poisoning supports the conclusion that these terms were not precise at all, especially when used by a "lay person"....just look at the way we use the term"yeast".
Also is the term "barmy" which is a metaphor for effervescent silliness...either in reference to the activity of the barm,or as a result of drinking aged barm which is of course alcoholic....its ancient ale (pre-lager). These ales actually predate the use of hops, which was considered an adulterant for a long while,and a cheap substitute for the herbs previously used,particularly heather, the most common...which has an hallucinogenic co-fungus on it when freshly cut...barmy! Also,this way of making bread from ale yeasts was described by Pliny when Caesar first campaigned in Gaul. The Romans had never seen it and much admired the bread of the Gauls (celtic French) and Iberians (Spanish)even then! I think this distinguishes the Celtic and Germanic bread making practices in antiquity, which have remained as the English/Scotch/Irish tradition of making bread with ale-barm,not sauertieg or Levain.
Barm making is quite a refined business,much more difficult than sourdough,and Australian bakers were expert at it. Using documented techniques of Australian bakers, my barms produce beautiful bread.
Interesting post from Dan Lepards site. I think you've probably asked the right bloke to comment as John has a very interesting handbook about barms and spons in Australia in the 1930's and I'm sure he's got lots of other sources material to drw from to contribute to this topic.
I have to confess to much ignorance in this aspect of baking and will read with interest. However, this really warrants its own thread so it doesn't get confused with other discussions. Go on, start a thread dedicated to this and over time we can watch it grow into a reference on barms and spons.
[quote=doughman]Danubian, out of curiosity...how long of a 1st and 2nd fermentation did you give these breads, and what % of starter did you add in the final dough? [/quote] <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
I guess here's an example of the need for a specific nomenclature for sourdough baking. Bakers in <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Australia have a nomenclature for many of their processes, etc. but not a specific nomenclature for the sourdough process, and to the extent that it exists, it's 'confused' as it's a hybrid of American and European, which have differences.
When you use the term "starter" you are referring to the acidified dough that's added to the final bread dough. This usage as far as I can tell is American. However, when I use the term "starter" I'm referring to the mature acidified dough used to inoculate a new batch of acidified dough that will be added to the final bread dough. As far as I can tell this usage is European.
To recapitulate;
American usage;
· starter = acidified dough added to the final bread dough (sourdough)
European usage;
· starter = mature sourdough used to inoculate a new batch of flour and water to become the acidified dough (sourdough)added to the final bread dough.
Doughman, this is not a criticism of your usage, only a clarification so we can both understand each other.
To answer your question, the first 50% rye - the sourdough ferments for approx. 6-8 hours (relatively short) at 24'C. This takes advantage of early yeast growth and C02 production. The level of addition is calculated on the basis of the total flour weight at 30%. The final bread dough has a relatively short DTO (Dough to Oven Time) - from the time the dough finishes mixing until it enters the oven - there's an example of bakers nomenclature. The bulk fermentation is approx. 2 1/2 - 3 hours at a relatively cool temp -approx 26'C - and final proof approx. 2 1/2 to 3 hours.
The second is entirely different. 20% Rye - the sourdough ferments for approx. 15 - 18hrs at 22'C. This takes advantage of Lactobacillus growth and acid production, pH and TA. The final dough has a relatively long DTO. Bulk fermentation for approx. 4 -5 hours at approx. 24'C and the final proof approx. 18hours (overnight in refrigerated environment for approx. 15 hours) and a final 3 hours at approx. 24'C.
Thanks for the clarification. Sometimes the 2 words are use interchangably over here. I guess the French equivalent would be levain. I was wondering about the . length of fermentation time for the 1st and 2nd fermentation of the 20% rye bread because I noticed the tiny blisters on the bread. My guess was right.
I realise those terms are interchangable but many don't, and it's
helpful and even proper that the baking trade in Australia adopts or
develops consistent definitions.
I like to use the European definition because it implies the
intermediate step of a seperate acidified dough (sourdough) prior to
and added to the final dough, as well as it being the medium to be
inoculated.
The French term "levain" is consistent with the European definition
above as it's also the intermediate step to be inoculated which is
added to the final dough after the levain (sourdough) matures. French
bakers refer to the "starter" as the "chef" which is the inoculant
that initiates the fermentation in the levain (sourdough).
I suppose it may seem like semantics to the home baker, but at a time
when science has achieved precise measurements and definitions, it
seems fitting to use as much precision as possible with our
definitions also.
Of course, you're free to choose to use your own terms and definitions but it makes for efficent communication if we agree on a standard language.
plastic scrapers to ensure the sides of the bowl are free of dough and flour particles that can dry out or as you say attract mould.
You mentioned you used fruit for two days? I soak the fruit skins in water for seven days, sometimes some of the skins exposed to the air (protruding from the water) are colonised by fine moulds. I just ignore that and strain off the liquid, discard the solids and use the liquid to form a dough with flour. This is then expanded through stages with time and used to ferment a bread dough.
Spontaneous sourdoughs made from fruit make some wonderful bread. The pity is that the particular aroma from the fruit used disappears from the sourdough after a week or so and to achieve the same aroma a new batch of fruit started dough needs to be made and used. Of course I'm talking about a speciality bread that relies on the fruit for it's aroma. The sourdough continues to be very good and as a fine sourdough but without the particular fruit aroma.
I'll never forget a batch of bread I made using a sourdough made from quince peels. (haven't made it since) My wife came home with some fresh quince which has a wonderfully pronounced tropical fruit salad aroma. The skins were fermented as described above. The sourdough had an amazing aroma of quince as if it was an essence oil. The bread was fantastic but over a week of cycling the sourdough it eventually lost the quince aroma reverting to a more normal sourdough.
Edit: I think the hijack started here. This should alert new readers to beware.
In terms of nomenclature,im not convinced that a bread fermented from a culture of fruit is technically a Sourdough. It is a fruit ferment,and these are distinct from a grain-leaven,particularly under organoleptic (that word sorry) or sensory analysis using corresponded or agreed criteria. I would also reckon that the yeast profile is different....apart from more complex analysis of the microbiology which is sure to be different..... This just demonstrates the variety of ferments possible when we get outside monoculture, and the need for some sort of taxonomy for these ferments. Must breads generated from a grape ferment,which i make often are very very different to my sourdoughs. As you say,these fruit ferments are ,or can be, exceptionally good breads,but i dont think they are sourdoughs, but as there is no taxonomy at all...or even trade standards...its just what i experience,and i think the sensory analysis bears out a clear difference.
There is a well documented tradition of using fruit yeasts(the blueberry was a favourite) to make sourdoughs in the American tradition, and apple ferments are well known in Europe,particularly with Rye. I reckon these yeasts morph after culturing with flour,and the rest of the microbiology comes more into line with what we know of SF sourdough for example. But this is in sharp distinction to the practices of classic French or Flemish levain generation. But these are also idiosyncratic.
Its not that any of these breads or methods are right or wrong,its just that we have lost the classifications of them in culinary culture, and it is enriching to restore them, and to be using them again.But its good to name them accurately...its culturally enriching. I think its so interesting that you have evolved this process,and its what makes one treasure a bakers true skill..."lets go to danubians bakery and get that rye he makes"
[quote=JohnD] <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
In terms of nomenclature,im not convinced that a bread fermented from a culture of fruit is technically a Sourdough. It is a fruit ferment,and these are distinct from a grain-leaven,particularly under organoleptic (that word sorry) or sensory analysis using corresponded or agreed criteria. I would also reckon that the yeast profile is different....apart from more complex analysis of the microbiology which is sure to be different.....
This just demonstrates the variety of ferments possible when we get outside monoculture, and the need for some sort of taxonomy for these ferments. Must breads generated from a grape ferment,which i make often are very very different to my sourdoughs. As you say,these fruit ferments are ,or can be, exceptionally good breads,but i dont think they are sourdoughs, but as there is no taxonomy at all...or even trade standards...its just what i experience,and i think the sensory analysis bears out a clear difference.
There is a well documented tradition of using fruit yeasts(the blueberry was a favourite) to make sourdoughs in the American tradition, and apple ferments are well known in Europe,particularly with <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Rye. I reckon these yeasts morph after culturing with flour,and the rest of the microbiology comes more into line with what we know of SF sourdough for example. But this is in sharp distinction to the practices of classic French or Flemish levain generation. But these are also idiosyncratic.
Its not that any of these breads or methods are right or wrong,its just that we have lost the classifications of them in culinary culture, and it is enriching to restore them, and to be using them again.But its good to name them accurately...its culturally enriching. I think its so interesting that you have evolved this process,and its what makes one treasure a bakers true skill..."lets go to danubians bakery and get that rye he makes"
[/quote]
I think you're definitely correct in your contentions about the differences in terms of microbiological profiles, and of course other flavours, aroma oils, and volatile substances which are part of the given fruit characteristics which give these types of [sour]doughs their sensory uniqueness. However, in my experience after cycling this type of culture in flour over a period of time they loose many of those sensory characteristics unless they are reinvigorated with a fresh culture, generationally closer to the specific fruit.
I'm prepared to agree with you that taxonomy is an invaluable tool which would enable bakers and customers to identify subtle and not so subtle differences and that seems to be sorely needed. I suppose the taxonomy of wine is an obvious example of what you're suggesting. Under this sort of taxonomy of the sourdough system it would enhance everybody’s understanding and could very well lead to the awareness of many idiosyncratic breads and methods not widely appreciated that should be appreciated.
Having said that, I believe the term "sourdough" is a 'generic' - genus - term that encompasses many types of cultures where various species of Lactobacillus and associated yeasts are introduced into bread doughs. The next step would be to devise specific names for the members of the genus.
What about when a sacc cerevisiae inoculated dough is aged and develops ripeness and "twang" indicating acidity and microflora?. I agree with you really, but perhaps there is a line as the guilds contended,and its to do with how the culture is generated?...from grain or fruit or wort...or monoculture. Seems like everything outside a monoculture is sourdough?...even a genuine sourdough which has Sacc C added?
[quote=JohnD]What about when a sacc cerevisiae inoculated dough is aged and develops ripeness and "twang" indicating acidity and microflora?. I agree with you really, but perhaps there is a line as the guilds contended,and its to do with how the culture is generated?...from grain or fruit or wort...or monoculture. Seems like everything outside a monoculture is sourdough?...even a genuine sourdough which has Sacc C added? [/quote]
I agree there needs to be a classification of every bread in relation to the entire constellation of the bread kingdom.
In my opinion the moment Saccharomyces cerevisiae is added to a sourdough its no longer sourdough, period!
I must caveat this statement with the admission that Sacc c is naturally present in healthy sourdoughs but in very small quantities They never assert themselves because they are kept in check by the natural tendency for sourdoughs to behave much like a relatively closed ecosystem. This is my main objection to labeling bread "yeast free" or "bakers yeast free", at best it's misleading, besides it just doesn't exist!
Saccharomyces cerevisiae (Sacc c) when added to a sourdough compete with Lactobacillus for maltose, and result is that Sacc c become the dominant microflora. Lactics are no longer able to influence the characteristics of the sourdough because their number decline. The endemic yeasts of healthy sourdoughs do not compete for maltose, they metabolise other simple sugars that Lactics do not. Of course there is some overlap but by and large it's nimiscule. Check Bergies Manual; you'll be able to identify which sugars are metabolised by which species of lactics and yeasts.
Hey this is gonna get complex,but ive never had anyone to take this journey,so thanks mate.....Theres a whole question about yeasts,because like viruses they are very dynamic organisms. Looking at yeasts and classifying them from a reductionist science`s view would lead us to believe that they are all morphologically quite distinct and identifiable. Everything neatly in its pigeon hole....which we now know its not...the pigeon flies.
Yep i agree putting sacc C in a sourdough renders it a not-sourdough. But youre saying that Sacc C exists in small quantities in a sourdough anyway...so is this a contradiction? And if this same Sacc C is endemic to the s/d,then why cant it compete with the bacteria and overcome them as the added Sacc C does?, given an "ecological" opportunity. (see blog on "the real thing").
It depends which Sacc C we are discussing.
Some experts like Ed Wood, an American microbiologist and sourdough maker (hes the guy who famously recreated Pharonic Egyptian bread for National Geographic) dont think that the yeast to which you refer as being Sacc C in sourdoughs , is actually Sacc C. He reckons its similar only,and that one couldnt actually be certain of that without an electron mic....and then not even....the only hope would be as you say classifying according to which carbs they metabolise, but this is demonstrably variable too..like viruses, yeasts are quantum critters....they morph so easily,and combine/mutate rapidly to suit the terroir.
But the Sacc C that bakers put in bread,isnt really the same Sacc C as this endemic one is it?
Apart from the GMO ones in UK,at very least, bakers Sacc C is seriously line bred and highly opportunistic/responsive, much like a thoroughbred horse compared to a draught horse...serious monoculture.
Sacc C naturally exists as a polyculture of families..which is a Barm in Gaelic-English, and desired strains are taken out and replicated in varying contexts until the required traits are found,and then that strain alone is used.
So the term "bakers yeast" is valid in so much as it defines a type of Sacc C. We used to use the term "brewers yeast" as a distinction to this.But we also know they were both Sacc C.
Just look at the difference between active dried yeast and the cake yeast which is available even.Those highly active dried yeasts actually die off quickly if you keep culturing them,or cycling the dough. Compressed yeast Sacc C lasts longer,but it dies off too, not from the threat of acidity but because they are hot-house flowers with no real virility.They require lots of refined carbs (read white sugar) to regenerate them,flour isnt enough,especially wholemeal.
Again,these Sacc C are really different to the Sacc C which one gets from a wort, of course full of maltose, which are incredibly robust and can be recycled from dough to dough and still be strong in action....as we know from documented historical Australian bakery practice.
I think the active dried yeast may be selected/bred to utilise sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which would also explain its lack of vigour.
So then,this is a bigger picture..which leads to the question of process...How was the yeast made? The whole fermentation process is a myriad, and clearly outstrips the tools we are trying to explain it with.Its not that our classifying/taxonomy is wrong,its just incomplete, and leaves out the possibilities of the fundamental of all realities...change. Ed sells various cultures hes collected from around the world,and he documents how different the yeasts are from various locations even. So our actual scientific taxonomy needs rewriting in terms of observable reality rather than intellectual convenience.We are still classifying a la Pasteur!
That means its prob better to use the term "bakers yeast" because it IS a special type of Sacc C. I agree its silly to call sourdough "yeast-free"....but consumers understand what this means, and want it.
[quote=JohnD]Hey this is gonna get complex,but ive never had anyone to take this journey,so thanks mate.....Theres a whole question about yeasts,because like viruses they are very dynamic organisms. Looking at yeasts and classifying them from a reductionist science`s view would lead us to believe that they are all morphologically quite distinct and identifiable. Everything neatly in its pigeon hole....which we now know its not...the pigeon flies.
Yep i agree putting sacc C in a sourdough renders it a not-sourdough. But youre saying that Sacc C exists in small quantities in a sourdough anyway...so is this a contradiction? And if this same Sacc C is endemic to the s/d,then why cant it compete with the bacteria and overcome them as the added Sacc C does?, given an "ecological" opportunity. (see blog on "the real thing").
It depends which Sacc C we are discussing.
Some experts like Ed Wood, an American microbiologist and sourdough maker (hes the guy who famously recreated Pharonic Egyptian bread for National Geographic) dont think that the yeast to which you refer as being Sacc C in sourdoughs , is actually Sacc C. He reckons its similar only,and that one couldnt actually be certain of that without an electron mic....and then not even....the only hope would be as you say classifying according to which carbs they metabolise, but this is demonstrably variable too..like viruses, yeasts are quantum critters....they morph so easily,and combine/mutate rapidly to suit the terroir.
But the Sacc C that bakers put in bread,isnt really the same Sacc C as this endemic one is it?
Apart from the GMO ones in UK,at very least, bakers Sacc C is seriously line bred and highly opportunistic/responsive, much like a thoroughbred horse compared to a draught horse...serious monoculture.
Sacc C naturally exists as a polyculture of families..which is a Barm in Gaelic-English, and desired strains are taken out and replicated in varying contexts until the required traits are found,and then that strain alone is used.
So the term "bakers yeast" is valid in so much as it defines a type of Sacc C. We used to use the term "brewers yeast" as a distinction to this.But we also know they were both Sacc C.
Just look at the difference between active dried yeast and the cake yeast which is available even.Those highly active dried yeasts actually die off quickly if you keep culturing them,or cycling the dough. Compressed yeast Sacc C lasts longer,but it dies off too, not from the threat of acidity but because they are hot-house flowers with no real virility.They require lots of refined carbs (read white sugar) to regenerate them,flour isnt enough,especially wholemeal.
Again,these Sacc C are really different to the Sacc C which one gets from a wort, of course full of maltose, which are incredibly robust and can be recycled from dough to dough and still be strong in action....as we know from documented historical Australian bakery practice.
I think the active dried yeast may be selected/bred to utilise sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which would also explain its lack of vigour.
So then,this is a bigger picture..which leads to the question of process...How was the yeast made? The whole fermentation process is a myriad, and clearly outstrips the tools we are trying to explain it with.Its not that our classifying/taxonomy is wrong,its just incomplete, and leaves out the possibilities of the fundamental of all realities...change. Ed sells various cultures hes collected from around the world,and he documents how different the yeasts are from various locations even. So our actual scientific taxonomy needs rewriting in terms of observable reality rather than intellectual convenience.We are still classifying a la Pasteur!
That means its prob better to use the term "bakers yeast" because it IS a special type of Sacc C. I agree its silly to call sourdough "yeast-free"....but consumers understand what this means, and want it.
[/quote]
I'd have to agree with you that the current taxonomy is inadequate to deal with the 'exceptions' as there seems to be enough of them to warrant a new 'rule' so to speak. Of course, strains of Sacc c which are called 'bakers yeast' bred by industrial plants exhibit a range of differences and characteristics compared to the endemic Sacc c of sourdoughs, and yes, they are continously monitored at the plant for consistent gassing power.
[quote][i]I think the active dried yeast may be selected/bred to utilise
sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which
would also explain its lack of vigour.[/i][/quote]
Not so, as far as I'm aware. These strains of Sacc c do metabolise sucrose, glucose and most importantly maltose. There isn't sufficient glucose or sucrose in a conventional bread dough to sustain gassing power into the initial baking stage without 'bakers yeast' also motabolising maltose. In fact enhanced amylase or diastatic activity is one of the important features of the rapid dough system and if the flour is deficient in alpha amylase - which Australian flours by and large tend to be - it's crittical to provide this additional diastatic activity as is common practice in rapid dough systems. But why? precisely because bakers yeast metabolises maltose, and in fact at the point where sucrose is exhausted it metaboiises maltose exclusively, it changes it's metabolic pathway.
However, to carry the point further, the industrial yeast plants I've visited, active dry bakers yeast is produced from the same batch as compressed bakers yeast although they are packaged dry in vaccum packs. They are indentical to compressed yeast. But you are correct to say there are some specific strains which have specialist applications such as frozen doughs, but they are in the main only a small specialised batch seperate from the common bakers yeast which is in compressed or dry form.
To reply to your contention that endemic Sacc c do not compete with Lactics on the basis that their presence but lack of dominance shows they do not metabolise maltose fails to take into consideration their small population in sourdoughs. As far as I understand the major reason for this is that they never reach crittical mass in a sourdough so pose no threat.
So where to from here; you've made some fair points which in my earlier
post I opted not to enter into on the basis that its a winding endless rabbit hole but to come to the issue of when is a sourdough not a sourdough can become a hair splitting exercise so I suppose we agree on most points but differ on others.
BTW I'm not familiar with Ed Wood's book except on a cursory basis, If you're willing can you post the ISBN so I can follow it up?
Intellectually it could be hair splitting,but in practice its plain: at no stage of the whole process from initiation to baking, is SaccC ADDED in any form...and this must include ambient contamination from a primarily yeast-using bakery.
[quote=JohnD]Intellectually it could be hair splitting,but in practice its plain: at no stage of the whole process from initiation to baking, is SaccC ADDED in any form...and this must include ambient contamination from a primarily yeast-using bakery.[/quote]
Yes, in the main it's plain, but I can't accept your statement ".....this must include ambient contamination from a primarily yeast-using bakery."
I would have thought the preceeding discussion had shown that a healthy sourdough will not be contaminated by ambient means in yeast using bakeries as Sacc c cells in an ambient process are nowhere near enough to reach crittical mass to endanger the sourdough's integrity.
Your statement doesn't follow logically, because if sourdoughs were "contaminated" by those means they would show characteristics of Lactobacillus decline, which they do not!
I've been using a sourdough from an original generation for more than 15 years without any decline in Lactics.
I can live with your repugnance of commercial yeast, but I cannot condone a dictatorial approach on the basis of a freedom limiting ideology. I suppose the roots of the next chapter of such a discussion may best be held over for another forum, when are you in Sydney next?
Hmm....would be a shame if, later, we can't find this animated discussion on sourdough nomenclature because it's embedded in Mould. Much of it can be shifted (if only it's that easy) to John's blog topic titled Sourdough Bread, the Real Thing or a new thread.
Feeling a bit heady (but loving it) from such spirited opinions... TP (*boing* *boing* aka Grasshopper)
[quote=TeckPoh]Hmm....would be a shame if, later, we can't find this animated discussion on sourdough nomenclature because it's embedded in Mould. [/quote]
[quote=Danubian][quote=TeckPoh]Hmm....would be a shame if, later, we can't find this animated discussion on sourdough nomenclature because it's embedded in Mould. [/quote]
You mean this thread hasn't gone mouldy, yet? [/quote]
Not at all! We all know that it's not so easy to kill off a starter/sourdough....just have to dig a bit deeper and refresh.
[quote=JohnD]Yep i agree putting sacc C in a sourdough renders it a not-sourdough.
But youre saying that Sacc C exists in small quantities in a sourdough
anyway...so is this a contradiction? And if this same Sacc C is endemic
to the s/d,then why cant it compete with the bacteria and overcome them
as the added Sacc C does?, given an "ecological" opportunity. (see blog
on "the real thing").[/quote]
You may be interested, (Spicher et al., 1979) isolated four sourdough yeasts and listed the sugars metabolised in two ways;
1. Fermentation (fer) 2. Assimilation (ass)
The table is much as you would find in Bergies Manual with positives (+) and negatives (-) to indicate which, are or are not, metabilised. For the sake of simplicity I've not listed those sugars which are negative but where a sugar is omitted from the list below the specific yeast indicates a negative for that sugar;
Picia saitoi
Glucose - fer, ass Athanol - ass
Candida Krusei
Glucose - fer, ass
Athanol - ass
Torulopsis holmii (Saccharomyces exiguus)
Glucose - fer, ass Galactose - fer, ass Saccharose - fer, ass Rafinose - 1/3fer, ass
Athanol - ass
Saccharomyces cerevisiae
Glucose - fer, ass
Galactose - fer, ass
Saccharose - fer, ass Maltose - fer, ass
Rafinose - 1/3fer, ass
Athanol - ass
Its revealing to note Sacc c is the only sourdough yeast to ferment and assimilate maltose yet they do not dominate or reach ascendancy but remain a minority population.
Replies
Dunno about mould being good, would start over! Where are you? How is the weather?Jeremy
I'm on the gold coast, so it's warm & humid.
Hi Della,
When was the last time it was cycled?
During storage when not cycling do you keep it refrigerated?
Is it covered while it's stored or fermenting?
Provided you've got a proven sourdough formula, you've followed it correctly, and you've maintain the fermentation parameters, it should be alright if you break the top surface by opening it to expose the fresh dough under it. Use the fresh dough and discard the outer moulded crust. Although? Mould can sometimes be a sign of poor lactobacillus activity.
If I make a spontaneous sourdough, I no longer use flour to culture the desirable microflora. I find the results more variable and requiring more cycles to achieve the desired microflora in the ascendency. I now use fruit skins for the initial culture period.
Jeremy, could well be right, and you may save yourself time to start from scratch. However, you could try it for three or five cycles using the fresh dough under the crust that's not mould infected. I'm willing to bet it'll be ok if you keep it refrigerated but cycle it regularly ensuring you keep to the schedule parameters.
It's a new starter (started from scratch last weekend) so all I've been doing so far is feeding, etc to try and get the right stuff growing!
I persevered with it, and it's looking fine today so I think I'll keep going - unless I get another mould convention in which case I'll give up :)
My hubby thinks I'm obsessed by sourdough - and I haven't even baked my first loaf yet! Apparently I keep going to stare at the starter....
at the prospect of making your own bread, there's a primeval resonance, a bit like hunting or growing your food.I've been baking for almost 30 years but I still get excited when I see great bread. Keep us informed of your progress, it'd be nice to see the fruits of your labour.
i remember reading that many types of mould are toxic and you should not eat anything with mould on it.
not sure what happens with mould during baking, maybe it becomes harmless?
if it was me i would make sure to refresh for few days and watch if it comes back.
I did mention that to begin a spontaneous sourdough I now use fruit as the original substrate to culture the desirable bacteria and yeasts and only after seven days do I introduce the liquid from this into a dough. I have had better results using this method comapred to using flour.
Lets see what happens over the next week.
Actually when I started the culture I use now I had mould issues as well. I started using fruit(organic grapes) as the original substrate and it got off to a bubbly start in a few days which I then poured into my dough mixture. But after the 2nd or 3rd feeding (I think) there was mould on the little bits of semi-dried dough that I didn't mix in properly with the rest of the mass. I think it was probably me being careless since by not keeping the sides of the container clean I left bits of dough (really small particles actually, but still) that didnt get to be fermented with the rest of the lot, other organisms kinda colonized it. I suppose cleaning the bits up with a wet paper towel would have probably made a difference.
But I just spooned out some of the good starter into a cleaner container and fed it again and it's been fine since. Lucky me!
Of course, to the uninitiated it looked beyond redemption. It was slightly mouldy and had a surface aroma with a Camembert backnote. The other bakers not familiar with sourdough were horrified that I was going to use it to start a sourdough. When I broke open the crust to reveal a bright paste underneath their fears were somewhat allayed.
However, I weighed up the flour, water, and the clean starter from under the discoloured mouldy crust in the desired proportions and mixed it for the desired time. Allowed it to ferment 15hrs; the fermentation was strong, aromatic, and the sourdough exhibited all the characteristics it should. Today I used the whole sourdough to again start a larger sourdough that will be used next week to make a variety of bread.
The missed opportunity lies in the fact that I didn't photograph it in its idle mouldy state and then in its recycled state for you to see it.
Anyway, I'll photograph the bread later next week and post it here so you can see that healthy sourdoughs are more robust than most imagine.
What should home bakers do with sour, keep it out and keep feeding daily, weekly? Or can some be stored in the fridge?
Jeremy
[quote=Jeremy]What about an acidic sourdough that sits in the fridge, is that spawn of satan?(John Downes gave it that moniker!)
What should home bakers do with sour, keep it out and keep feeding daily, weekly? Or can some be stored in the fridge?
[/quote]
G'day Jeremy, "acidic sourdough"? Am I correct to assume you're referring to a sourdough that is over mature and has an acetate aroma? (Akin to 'butyl acetate' a bit like nail polish remover) Is this what you're referring to?
In the case I outlined in the previous post where the starter sat idle for 10 weeks the starter was actually a mature sourdough that was refrigerated immediately after the conclusion of the specified fermentation time. This means that it was at its peak in viable microbe numbers and the fermentation had not continued to form significant quantities of more exotic by-products such as acetates and lactylates. This was done precisely because it was to be stored for an extended period. In our case we were leaving for summer holidays and were not to return until the beginning of February. My reason for posting this example was to show Della that once a healthy sourdough is achieved it should continue to remain relatively viable even if moulds appear on the surface.
In the case of home bakers I'd suggest keep baking and refreshing your sourdoughs regularly. The more often the sourdough is cycled within tried and tested parameters the better its resilience. I would also use the refrigerator when the sourdough is outside the specified fermentation time. The reason for this is to retard the production of fermentation by-products. I've seen home bakers mystified by the variation they find in their bread from one day to the other in spite of insisting they did..."everything the same" and upon questioning it becomes clear their sourdough maturity has varied due to lack of consistent fermentation times. The fridge can mitigate extended fermentation times by simple temperature control.
However, John's advice to Ruth - [url=http://sourdough.com.au/?q=forum/topic/1103#comment-8347][b]see here[/b][/url] - makes plenty of sense. For commercial bakers consistency is critical but for home bakers there plenty of acceptable latitude. Besides, its better for it to be an enjoyable experience and not a source of anxiety or pressure. Sometimes I just don't feel like baking, so I don't. It gives me a chance to grab some bread from one of the sourdough bakeries and try something new.
I hope I've answered your question without being tedious.
I too can attest to your statement with success. I too left my starter in the refrigerator, but it was for only 3 weeks. When I came back, there was "hooch" on the top of the starter but no mold that I could detect. I discarded the liquid and proceeded to feed my over starved starter. After about 4 days of feeding, my starter was back to life.
Ok, I had no idea it was called hooch. Do you know the origins of the word "hooch" in this context?
If I find my sourdough that has been sitting for a while and develops hooch, I use the paste, much like you, TP, from under the liquid or crust to cycle it. I have never used it directly into a bread dough.
Jeremy
[IMG]http://i22.photobucket.com/albums/b317/plutrach/IMG_4789.jpg[/IMG]
[IMG]http://i22.photobucket.com/albums/b317/plutrach/IMG_4796.jpg[/IMG]
It was cycled again over night and there will be more bread (different type) tomorrow.
50% rye and 50% bakers flour.
The rye is from Weston milling and is a very low extraction rye - endosperm only - I've contacted them for a report which will among other things have the ash content. The bakers flour will have .550 ash content.
The young apprentice who made those loaves was very proud of the results. Thanks for the compliments.
[img]http://sourdough.com.au/gallery2/main.php?g2_view=core.DownloadItem&g2_i...
Crust detail
[img]http://sourdough.com.au/gallery2/main.php?g2_view=core.DownloadItem&g2_i...
Crumb detail
[img]http://sourdough.com.au/gallery2/main.php?g2_view=core.DownloadItem&g2_i...
John,
Do you think sourdough should have a Rheinheitsgebot (purity code or law?) and who would administer those rules?
Jeremy
John,
Do you think sourdough should have a Rheinheitsgebot (purity code or law?) and who would administer those rules?
[/quote]
Jeremy, I'm not too keen on 'administers' of anything, for good reasons, but I can see the need to have clear definitions. In the past the Trade Guilds were the custodians of these matters.
Of course i do Jeremy, but..."as if"...even the Germans are now allowing sugar in beer!!! It would be good because it sperates wheat from chaff,ie,the consumer knows what they are getting,and that has two aspects.
Firstly,ive got a right to know that i am getting what i pay for, its contractual law actually. At present one can purchase a "sourdough" completely made with yeast and having no sourdough microbiology at all, they are everywhere. Thats a fraud,but we have bakers, writers and educators who dont know or care, or think that sourdough is just a name to be exploited.So from the point of our culinary culture,it means everything is just a mush (mutton is lamb and honey is sugar), and consumers are fair game.
On a more serious note,it is documented that genuine sourdough bread is therapeutic,notably with type 2 diabetes. A diabetic who is aware or this and seeks remission through dietary means,using s/d, will not get that benefit, and thats a clinical fraud really.
Also,as an Artisan making genuine sourdough bread,my trade is reduced by unfair competition from those who fake their sourdoughs. Im not sure,but i reckon this actually breaches the Trade Practices Act. I sell less because there are analogs out there. This is not allowed in other trades.
The big problem is that there are no Trade standards,and frankly i dont think the trade cares.Consumers do,and are becoming more informed than the bakers themselves.
But as far as what i was saying about the fruit ferments which Danubian is doing,well thats just good news really,and as we have the pleasure of enjoying Pils or lager or ale, or shiraz ,sangiovese or nebbiolo, it enriches our enjoyment of proper food, and is a plus for the trade.
Its just a shame all of this gets lost ,unlike in the wine or cheese industry which promote authenticity and diversity, because the bakery trade is frankly,braindead.
Even beer one of my favored fermented beverages has been neutered, watered down, and dare I say it, taken over by the largest multinationals! Thank goodness for small underground food culture, but even there craft is hodge-podge I think? My own humble opinion. And what about craft guilds, are those also too restraining in terms of individual efforts, what your opinion?
Should do another interview, got to get the other edited still, bloody hell!
Cheers
[quote=JohnD]Its just a shame all of this gets lost ,unlike in the wine or cheese industry which promote authenticity and diversity, because the bakery trade is frankly,braindead.[/quote]
I have to agree with most of your post. However, not all are "braindead", you - although you may not consider yourself part of the "Baking Industry" you are! - and I are examples of enlightened bakers. There are many others and our ranks are swelling by the day.
http://www.danlepard.com/forum/viewtopic.php?t=117&postdays=0&postorder=...
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Barm - An old word, the name for the thick froth produced in brewers' vats, and sold for breadmaking purposes, and for brewing of home-brewed ales, ginger beer, and treacle beers.
In the trial of the Earl of Somerset for high treason and for the murder of Sir Thomas Overbury, in the reign of James I, the arraigning counsel, Sir Francis Bacon, mentions barm, or yeast, as an agent for poisoning.
"As we may see in the example of Henry VIII, that where the purpose was to poison one man, there was poison put into barm or yeast; and with the barm, pottage or gruel was made, whereby sixteen of the Bishop of Rochester's servants were poisoned."
Thus the word barm, with a precise if sinister meaning and association, was in use over three hundred years ago. The term is still used in country districts as meaning brewer's yeast, and in some parts is even applied to pressed yeast.
But since bakers, or others for them, began to make a fermenting agent for themselves, about 1800, that has been described as barm, while the word yeast has been retained for the brewery product, as well as for the more modern article sold in solid form.
Barm contains yeast cells, generally of a variety of species, as well as some of the liquor in which the yeast has been grown. Barms are of many kinds, and of all degrees of "strength"; that is, a particular lot may contain few or many yeast cells, and much or little of the acids, peptones, alcohols, &c., which have resulted from previous fermentations.
Probably the earliest barm made, as distinguished from leavens, was that from malt and hops, as the baker in the first instance merely copied the brewer or the distiller. This barm was known as "compound", or "comp", or "patent". Some makers used a quantity of flour in the mixture, some did not.
In Scotland, where barms were first made, and where they still continue in favour, the compound barm was displaced by a kind made with scalded flour and malt. To this was given the name of " Parisian ", although there is no precise evidence to show that it was copied from the practice of Parisian bakers. Another sort which may contain a little malt, but may be all scalded and raw flour, is called " Virgin Barm ".
A kind much used in Australia, South Africa, &c., has boiled potatoes, sugar, baked flour, and bran as the constituents of the mash. This is called " spontaneous", or "spon", probably because, in the regions in which it is used, the liquid will start fermenting without a "stock" of old barm, and mature sufficiently to be used for breadmaking, by a straight dough process, under such conditions in about 30 hours.
Barms have, of course, to be used in comparatively large quantity. It is a strong barm that contains 12 oz. of yeast to the gallon, and the work is done by the yeast cells only. Barms have much influence on the nature of the bread. Flour barms produce a condition of crumb that might be described as raw: it seems moist and slightly clinging, but the bread is white and its skin smooth.
As a rule, except in the case of "spontaneous " referred to above, barms are used with a long process of fermentation, either in two or three stages, and the flavours attributed to the barm may be due really to the changes in material within the dough, resulting from the processes.
To drive off the alcohol and to gelatinize the starch. For a little more detail about the changes that occur, here is a passage from William Jago's classic late 19th century treatise, 'The Science and Art of Breadmaking' (Simpkin, Marshall, Hamilton, Kent & Co., London, 1895)
'The barm tub and contents are left in the brew-house uncovered for 21 hours or so. During that time the mixture, undergoes several changes. The scalding water bursts a proportion of the starch granules of the flour, converting them into starch paste: the diastase of the malt inverts or hydrates this paste into a sugar, maltose, and a brown, gummy body, dextrin. The mixture, after scalding, tastes very sweet; in half an hour after it is sweeter, and thinner, and browner. These changes continue for several hours, then a distinct acid taste is felt.'
Simply to add complexity to the flavour of the barm.
You would have made a new one at the end of the week, otherwise the ferment becomes sour. And sourness wasn't an intention of bakers, but rather something to avoid as it stopped bread selling - we didn't have a big tradition of sour flavours in the British diet, even our pickles are sweet.
But… now we do. However, if you were to simply refresh the barm with flour and water the result would eventually be no different to a leaven. So I would remake the barm from scratch in order to keep a hoppy taste to the loaf.
For a much sharper and brighter taste to the loaf, omit the water from the final dough and decrease the flour and salt accordingly (to your preference, and chosen crumb structure)
I'll say it once again. A starter or leaven made from beer yeast, flour and water is just that. A barm, however, as known by bakers working up until the introduction of compressed German yeast, is a gelatinized mixture of mashed malted grains, hops and flour. As the traditional recipe is very complicated and involves mashing malted grains and boiling hops, I have written a recipe that takes live beer and attempts to take it back a stage prior to fermentation creating alcohol, by heating the mixture both to gelatinize the flour and to try and return beer to its state before fermentation commenced.
Is there a difference between a barm and a starter made from a live beer?
Yes. A 'starter made from live beer' is a starter made from live beer. A barm is a gelatinized mixture of mashed malted grains, hops and flour.
Could you touch on this topic a bit and it's role within sourdough?
I have a different view. A Parisian barm only,is made with the boiling water used to gelatinise the starch in flour, and malt is added,according to sources ive read,and this is attested by the fact that this barm is called "Parisian",which means it is distinguised from a "regular" barm, usually grown on a wort of malted grains, seeded from a "stock".
But to be definitive about a historical term is fraught,especially as it is source dependant and there are few sources, and these cannot be seen as covering the whole gamut of usage. We are not talking scientific taxonomy here,but very fluid colloquial language. The bit about the poisoning supports the conclusion that these terms were not precise at all, especially when used by a "lay person"....just look at the way we use the term"yeast".
Also is the term "barmy" which is a metaphor for effervescent silliness...either in reference to the activity of the barm,or as a result of drinking aged barm which is of course alcoholic....its ancient ale (pre-lager). These ales actually predate the use of hops, which was considered an adulterant for a long while,and a cheap substitute for the herbs previously used,particularly heather, the most common...which has an hallucinogenic co-fungus on it when freshly cut...barmy! Also,this way of making bread from ale yeasts was described by Pliny when Caesar first campaigned in Gaul. The Romans had never seen it and much admired the bread of the Gauls (celtic French) and Iberians (Spanish)even then! I think this distinguishes the Celtic and Germanic bread making practices in antiquity, which have remained as the English/Scotch/Irish tradition of making bread with ale-barm,not sauertieg or Levain.
Barm making is quite a refined business,much more difficult than sourdough,and Australian bakers were expert at it. Using documented techniques of Australian bakers, my barms produce beautiful bread.
I have to confess to much ignorance in this aspect of baking and will read with interest. However, this really warrants its own thread so it doesn't get confused with other discussions. Go on, start a thread dedicated to this and over time we can watch it grow into a reference on barms and spons.
[quote=doughman]Danubian, out of curiosity...how long of a 1st and 2nd fermentation did you give these breads, and what % of starter did you add in the final dough?
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I guess here's an example of the need for a specific nomenclature for sourdough baking. Bakers in <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Australia have a nomenclature for many of their processes, etc. but not a specific nomenclature for the sourdough process, and to the extent that it exists, it's 'confused' as it's a hybrid of American and European, which have differences.
When you use the term "starter" you are referring to the acidified dough that's added to the final bread dough. This usage as far as I can tell is American. However, when I use the term "starter" I'm referring to the mature acidified dough used to inoculate a new batch of acidified dough that will be added to the final bread dough. As far as I can tell this usage is European.
To recapitulate;
American usage;
· starter = acidified dough added to the final bread dough (sourdough)
European usage;
· starter = mature sourdough used to inoculate a new batch of flour and water to become the acidified dough (sourdough)added to the final bread dough.
Doughman, this is not a criticism of your usage, only a clarification so we can both understand each other.
To answer your question, the first 50% rye - the sourdough ferments for approx. 6-8 hours (relatively short) at 24'C. This takes advantage of early yeast growth and C02 production. The level of addition is calculated on the basis of the total flour weight at 30%. The final bread dough has a relatively short DTO (Dough to Oven Time) - from the time the dough finishes mixing until it enters the oven - there's an example of bakers nomenclature. The bulk fermentation is approx. 2 1/2 - 3 hours at a relatively cool temp -approx 26'C - and final proof approx. 2 1/2 to 3 hours.
The second is entirely different. 20% Rye - the sourdough ferments for approx. 15 - 18hrs at 22'C. This takes advantage of Lactobacillus growth and acid production, pH and TA. The final dough has a relatively long DTO. Bulk fermentation for approx. 4 -5 hours at approx. 24'C and the final proof approx. 18hours (overnight in refrigerated environment for approx. 15 hours) and a final 3 hours at approx. 24'C.
Thanks for the clarification. Sometimes the 2 words are use interchangably over here. I guess the French equivalent would be levain. I was wondering about the .
length of fermentation time for the 1st and 2nd fermentation of the 20% rye bread because I noticed the tiny blisters on the bread. My guess was right.
I like to use the European definition because it implies the intermediate step of a seperate acidified dough (sourdough) prior to and added to the final dough, as well as it being the medium to be inoculated.
The French term "levain" is consistent with the European definition above as it's also the intermediate step to be inoculated which is added to the final dough after the levain (sourdough) matures. French bakers refer to the "starter" as the "chef" which is the inoculant that initiates the fermentation in the levain (sourdough).
I suppose it may seem like semantics to the home baker, but at a time when science has achieved precise measurements and definitions, it seems fitting to use as much precision as possible with our definitions also.
Of course, you're free to choose to use your own terms and definitions but it makes for efficent communication if we agree on a standard language.
You mentioned you used fruit for two days? I soak the fruit skins in water for seven days, sometimes some of the skins exposed to the air (protruding from the water) are colonised by fine moulds. I just ignore that and strain off the liquid, discard the solids and use the liquid to form a dough with flour. This is then expanded through stages with time and used to ferment a bread dough.
Spontaneous sourdoughs made from fruit make some wonderful bread. The pity is that the particular aroma from the fruit used disappears from the sourdough after a week or so and to achieve the same aroma a new batch of fruit started dough needs to be made and used. Of course I'm talking about a speciality bread that relies on the fruit for it's aroma. The sourdough continues to be very good and as a fine sourdough but without the particular fruit aroma.
I'll never forget a batch of bread I made using a sourdough made from quince peels. (haven't made it since) My wife came home with some fresh quince which has a wonderfully pronounced tropical fruit salad aroma. The skins were fermented as described above. The sourdough had an amazing aroma of quince as if it was an essence oil. The bread was fantastic but over a week of cycling the sourdough it eventually lost the quince aroma reverting to a more normal sourdough.
Edit: I think the hijack started here. This should alert new readers to beware.
[img]http://www.englishforum.ch/attachments/family-matters/98d1158920230-kind...
In terms of nomenclature,im not convinced that a bread fermented from a culture of fruit is technically a Sourdough. It is a fruit ferment,and these are distinct from a grain-leaven,particularly under organoleptic (that word sorry) or sensory analysis using corresponded or agreed criteria. I would also reckon that the yeast profile is different....apart from more complex analysis of the microbiology which is sure to be different..... This just demonstrates the variety of ferments possible when we get outside monoculture, and the need for some sort of taxonomy for these ferments. Must breads generated from a grape ferment,which i make often are very very different to my sourdoughs. As you say,these fruit ferments are ,or can be, exceptionally good breads,but i dont think they are sourdoughs, but as there is no taxonomy at all...or even trade standards...its just what i experience,and i think the sensory analysis bears out a clear difference.
There is a well documented tradition of using fruit yeasts(the blueberry was a favourite) to make sourdoughs in the American tradition, and apple ferments are well known in Europe,particularly with Rye. I reckon these yeasts morph after culturing with flour,and the rest of the microbiology comes more into line with what we know of SF sourdough for example. But this is in sharp distinction to the practices of classic French or Flemish levain generation. But these are also idiosyncratic.
Its not that any of these breads or methods are right or wrong,its just that we have lost the classifications of them in culinary culture, and it is enriching to restore them, and to be using them again.But its good to name them accurately...its culturally enriching. I think its so interesting that you have evolved this process,and its what makes one treasure a bakers true skill..."lets go to danubians bakery and get that rye he makes"
[quote=JohnD] <?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />
In terms of nomenclature,im not convinced that a bread fermented from a culture of fruit is technically a Sourdough. It is a fruit ferment,and these are distinct from a grain-leaven,particularly under organoleptic (that word sorry) or sensory analysis using corresponded or agreed criteria. I would also reckon that the yeast profile is different....apart from more complex analysis of the microbiology which is sure to be different.....
This just demonstrates the variety of ferments possible when we get outside monoculture, and the need for some sort of taxonomy for these ferments. Must breads generated from a grape ferment,which i make often are very very different to my sourdoughs. As you say,these fruit ferments are ,or can be, exceptionally good breads,but i dont think they are sourdoughs, but as there is no taxonomy at all...or even trade standards...its just what i experience,and i think the sensory analysis bears out a clear difference.
There is a well documented tradition of using fruit yeasts(the blueberry was a favourite) to make sourdoughs in the American tradition, and apple ferments are well known in Europe,particularly with <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />Rye. I reckon these yeasts morph after culturing with flour,and the rest of the microbiology comes more into line with what we know of SF sourdough for example. But this is in sharp distinction to the practices of classic French or Flemish levain generation. But these are also idiosyncratic.
Its not that any of these breads or methods are right or wrong,its just that we have lost the classifications of them in culinary culture, and it is enriching to restore them, and to be using them again.But its good to name them accurately...its culturally enriching. I think its so interesting that you have evolved this process,and its what makes one treasure a bakers true skill..."lets go to danubians bakery and get that rye he makes"
[/quote]
I think you're definitely correct in your contentions about the differences in terms of microbiological profiles, and of course other flavours, aroma oils, and volatile substances which are part of the given fruit characteristics which give these types of [sour]doughs their sensory uniqueness. However, in my experience after cycling this type of culture in flour over a period of time they loose many of those sensory characteristics unless they are reinvigorated with a fresh culture, generationally closer to the specific fruit.
I'm prepared to agree with you that taxonomy is an invaluable tool which would enable bakers and customers to identify subtle and not so subtle differences and that seems to be sorely needed. I suppose the taxonomy of wine is an obvious example of what you're suggesting. Under this sort of taxonomy of the sourdough system it would enhance everybody’s understanding and could very well lead to the awareness of many idiosyncratic breads and methods not widely appreciated that should be appreciated.
Having said that, I believe the term "sourdough" is a 'generic' - genus - term that encompasses many types of cultures where various species of Lactobacillus and associated yeasts are introduced into bread doughs. The next step would be to devise specific names for the members of the genus.
[quote=JohnD]What about when a sacc cerevisiae inoculated dough is aged and develops ripeness and "twang" indicating acidity and microflora?. I agree with you really, but perhaps there is a line as the guilds contended,and its to do with how the culture is generated?...from grain or fruit or wort...or monoculture. Seems like everything outside a monoculture is sourdough?...even a genuine sourdough which has Sacc C added?
[/quote]
I agree there needs to be a classification of every bread in relation to the entire constellation of the bread kingdom.
In my opinion the moment Saccharomyces cerevisiae is added to a sourdough its no longer sourdough, period!
I must caveat this statement with the admission that Sacc c is naturally present in healthy sourdoughs but in very small quantities They never assert themselves because they are kept in check by the natural tendency for sourdoughs to behave much like a relatively closed ecosystem. This is my main objection to labeling bread "yeast free" or "bakers yeast free", at best it's misleading, besides it just doesn't exist!
Saccharomyces cerevisiae (Sacc c) when added to a sourdough compete with Lactobacillus for maltose, and result is that Sacc c become the dominant microflora. Lactics are no longer able to influence the characteristics of the sourdough because their number decline. The endemic yeasts of healthy sourdoughs do not compete for maltose, they metabolise other simple sugars that Lactics do not. Of course there is some overlap but by and large it's nimiscule. Check Bergies Manual; you'll be able to identify which sugars are metabolised by which species of lactics and yeasts.
Hey this is gonna get complex,but ive never had anyone to take this journey,so thanks mate.....Theres a whole question about yeasts,because like viruses they are very dynamic organisms. Looking at yeasts and classifying them from a reductionist science`s view would lead us to believe that they are all morphologically quite distinct and identifiable. Everything neatly in its pigeon hole....which we now know its not...the pigeon flies.
Yep i agree putting sacc C in a sourdough renders it a not-sourdough. But youre saying that Sacc C exists in small quantities in a sourdough anyway...so is this a contradiction? And if this same Sacc C is endemic to the s/d,then why cant it compete with the bacteria and overcome them as the added Sacc C does?, given an "ecological" opportunity. (see blog on "the real thing").
It depends which Sacc C we are discussing.
Some experts like Ed Wood, an American microbiologist and sourdough maker (hes the guy who famously recreated Pharonic Egyptian bread for National Geographic) dont think that the yeast to which you refer as being Sacc C in sourdoughs , is actually Sacc C. He reckons its similar only,and that one couldnt actually be certain of that without an electron mic....and then not even....the only hope would be as you say classifying according to which carbs they metabolise, but this is demonstrably variable too..like viruses, yeasts are quantum critters....they morph so easily,and combine/mutate rapidly to suit the terroir.
But the Sacc C that bakers put in bread,isnt really the same Sacc C as this endemic one is it?
Apart from the GMO ones in UK,at very least, bakers Sacc C is seriously line bred and highly opportunistic/responsive, much like a thoroughbred horse compared to a draught horse...serious monoculture.
Sacc C naturally exists as a polyculture of families..which is a Barm in Gaelic-English, and desired strains are taken out and replicated in varying contexts until the required traits are found,and then that strain alone is used.
So the term "bakers yeast" is valid in so much as it defines a type of Sacc C. We used to use the term "brewers yeast" as a distinction to this.But we also know they were both Sacc C.
Just look at the difference between active dried yeast and the cake yeast which is available even.Those highly active dried yeasts actually die off quickly if you keep culturing them,or cycling the dough. Compressed yeast Sacc C lasts longer,but it dies off too, not from the threat of acidity but because they are hot-house flowers with no real virility.They require lots of refined carbs (read white sugar) to regenerate them,flour isnt enough,especially wholemeal.
Again,these Sacc C are really different to the Sacc C which one gets from a wort, of course full of maltose, which are incredibly robust and can be recycled from dough to dough and still be strong in action....as we know from documented historical Australian bakery practice.
I think the active dried yeast may be selected/bred to utilise sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which would also explain its lack of vigour.
So then,this is a bigger picture..which leads to the question of process...How was the yeast made? The whole fermentation process is a myriad, and clearly outstrips the tools we are trying to explain it with.Its not that our classifying/taxonomy is wrong,its just incomplete, and leaves out the possibilities of the fundamental of all realities...change. Ed sells various cultures hes collected from around the world,and he documents how different the yeasts are from various locations even. So our actual scientific taxonomy needs rewriting in terms of observable reality rather than intellectual convenience.We are still classifying a la Pasteur!
That means its prob better to use the term "bakers yeast" because it IS a special type of Sacc C. I agree its silly to call sourdough "yeast-free"....but consumers understand what this means, and want it.
Yep i agree putting sacc C in a sourdough renders it a not-sourdough. But youre saying that Sacc C exists in small quantities in a sourdough anyway...so is this a contradiction? And if this same Sacc C is endemic to the s/d,then why cant it compete with the bacteria and overcome them as the added Sacc C does?, given an "ecological" opportunity. (see blog on "the real thing").
It depends which Sacc C we are discussing.
Some experts like Ed Wood, an American microbiologist and sourdough maker (hes the guy who famously recreated Pharonic Egyptian bread for National Geographic) dont think that the yeast to which you refer as being Sacc C in sourdoughs , is actually Sacc C. He reckons its similar only,and that one couldnt actually be certain of that without an electron mic....and then not even....the only hope would be as you say classifying according to which carbs they metabolise, but this is demonstrably variable too..like viruses, yeasts are quantum critters....they morph so easily,and combine/mutate rapidly to suit the terroir.
But the Sacc C that bakers put in bread,isnt really the same Sacc C as this endemic one is it?
Apart from the GMO ones in UK,at very least, bakers Sacc C is seriously line bred and highly opportunistic/responsive, much like a thoroughbred horse compared to a draught horse...serious monoculture.
Sacc C naturally exists as a polyculture of families..which is a Barm in Gaelic-English, and desired strains are taken out and replicated in varying contexts until the required traits are found,and then that strain alone is used.
So the term "bakers yeast" is valid in so much as it defines a type of Sacc C. We used to use the term "brewers yeast" as a distinction to this.But we also know they were both Sacc C.
Just look at the difference between active dried yeast and the cake yeast which is available even.Those highly active dried yeasts actually die off quickly if you keep culturing them,or cycling the dough. Compressed yeast Sacc C lasts longer,but it dies off too, not from the threat of acidity but because they are hot-house flowers with no real virility.They require lots of refined carbs (read white sugar) to regenerate them,flour isnt enough,especially wholemeal.
Again,these Sacc C are really different to the Sacc C which one gets from a wort, of course full of maltose, which are incredibly robust and can be recycled from dough to dough and still be strong in action....as we know from documented historical Australian bakery practice.
I think the active dried yeast may be selected/bred to utilise sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which would also explain its lack of vigour.
So then,this is a bigger picture..which leads to the question of process...How was the yeast made? The whole fermentation process is a myriad, and clearly outstrips the tools we are trying to explain it with.Its not that our classifying/taxonomy is wrong,its just incomplete, and leaves out the possibilities of the fundamental of all realities...change. Ed sells various cultures hes collected from around the world,and he documents how different the yeasts are from various locations even. So our actual scientific taxonomy needs rewriting in terms of observable reality rather than intellectual convenience.We are still classifying a la Pasteur!
That means its prob better to use the term "bakers yeast" because it IS a special type of Sacc C. I agree its silly to call sourdough "yeast-free"....but consumers understand what this means, and want it.
[/quote]I'd have to agree with you that the current taxonomy is inadequate to deal with the 'exceptions' as there seems to be enough of them to warrant a new 'rule' so to speak. Of course, strains of Sacc c which are called 'bakers yeast' bred by industrial plants exhibit a range of differences and characteristics compared to the endemic Sacc c of sourdoughs, and yes, they are continously monitored at the plant for consistent gassing power.
[quote][i]I think the active dried yeast may be selected/bred to utilise sucrose/glucose more than maltose? Kind of a "diabetic" yeast, which would also explain its lack of vigour.[/i][/quote]
Not so, as far as I'm aware. These strains of Sacc c do metabolise sucrose, glucose and most importantly maltose. There isn't sufficient glucose or sucrose in a conventional bread dough to sustain gassing power into the initial baking stage without 'bakers yeast' also motabolising maltose. In fact enhanced amylase or diastatic activity is one of the important features of the rapid dough system and if the flour is deficient in alpha amylase - which Australian flours by and large tend to be - it's crittical to provide this additional diastatic activity as is common practice in rapid dough systems. But why? precisely because bakers yeast metabolises maltose, and in fact at the point where sucrose is exhausted it metaboiises maltose exclusively, it changes it's metabolic pathway.
However, to carry the point further, the industrial yeast plants I've visited, active dry bakers yeast is produced from the same batch as compressed bakers yeast although they are packaged dry in vaccum packs. They are indentical to compressed yeast. But you are correct to say there are some specific strains which have specialist applications such as frozen doughs, but they are in the main only a small specialised batch seperate from the common bakers yeast which is in compressed or dry form.
To reply to your contention that endemic Sacc c do not compete with Lactics on the basis that their presence but lack of dominance shows they do not metabolise maltose fails to take into consideration their small population in sourdoughs. As far as I understand the major reason for this is that they never reach crittical mass in a sourdough so pose no threat.
So where to from here; you've made some fair points which in my earlier post I opted not to enter into on the basis that its a winding endless rabbit hole but to come to the issue of when is a sourdough not a sourdough can become a hair splitting exercise so I suppose we agree on most points but differ on others.
BTW I'm not familiar with Ed Wood's book except on a cursory basis, If you're willing can you post the ISBN so I can follow it up?
Thanks.
Yes, in the main it's plain, but I can't accept your statement ".....this must include ambient contamination from a primarily yeast-using bakery."
I would have thought the preceeding discussion had shown that a healthy sourdough will not be contaminated by ambient means in yeast using bakeries as Sacc c cells in an ambient process are nowhere near enough to reach crittical mass to endanger the sourdough's integrity.
Your statement doesn't follow logically, because if sourdoughs were "contaminated" by those means they would show characteristics of Lactobacillus decline, which they do not!
I've been using a sourdough from an original generation for more than 15 years without any decline in Lactics.
I can live with your repugnance of commercial yeast, but I cannot condone a dictatorial approach on the basis of a freedom limiting ideology. I suppose the roots of the next chapter of such a discussion may best be held over for another forum, when are you in Sydney next?
Feeling a bit heady (but loving it) from such spirited opinions...
TP (*boing* *boing* aka Grasshopper)
You mean this thread hasn't gone mouldy, yet?
You mean this thread hasn't gone mouldy, yet?
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Not at all! We all know that it's not so easy to kill off a starter/sourdough....just have to dig a bit deeper and refresh.
Not me I am still wanting a thread on Desem and barm!
TeeeeHeeeee!
You may be interested, (Spicher et al., 1979) isolated four sourdough yeasts and listed the sugars metabolised in two ways;
1. Fermentation (fer)
2. Assimilation (ass)
The table is much as you would find in Bergies Manual with positives (+) and negatives (-) to indicate which, are or are not, metabilised. For the sake of simplicity I've not listed those sugars which are negative but where a sugar is omitted from the list below the specific yeast indicates a negative for that sugar;
- Picia saitoi
Glucose - fer, assAthanol - ass
- Candida Krusei
Glucose - fer, assAthanol - ass
- Torulopsis holmii (Saccharomyces exiguus)
Glucose - fer, assGalactose - fer, ass
Saccharose - fer, ass
Rafinose - 1/3fer, ass
Athanol - ass
- Saccharomyces cerevisiae
Glucose - fer, assGalactose - fer, ass
Saccharose - fer, ass
Maltose - fer, ass
Rafinose - 1/3fer, ass
Athanol - ass
Its revealing to note Sacc c is the only sourdough yeast to ferment and assimilate maltose yet they do not dominate or reach ascendancy but remain a minority population.
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