Blistered glaze like crust...?


great to see a sourdough forum down under... and such a nicely organised one at that... congrats!!

what I have for a long time been wondering is how do the bakers get the blistered glaze like in this spelt roll from Sonoma Bakery [url][/url]...??

here in South Australia the, what now seems defunct, Matisse Bakery used to get the same crust and I have often tried to find out how to do it... but with no success



Blisters come from the acidity level in the dough brought about by the level of levain used as well as by a long cool final proof, normally around 10c, for around 10 - 12hr, or also by retarding at 3 - 4c for similar periods or even over night.

The shiny crust comes from the break down of proteins in the crust due to the longer final proof leaving a higher level of starch, this combined with the addition of moisture at point of baking either via spray or steam injection causes a shiny finish. Similar principle as to the starch glazes like thosed used on traditional rye breads.


"Lifes Short, Bake Hard"

Merci à SourDom pour la réponse en français. J'apprécie l'effort. - Thank you to SourDom for the answer in French. I appreciate.

Northwestsourdough, nice pictures. [img][/img]
I understand that people can search for this effect because it is the mark of a slow fermentation and, so, usually a promise of a nice taste.
For me, I don't really care about the blisters. If the bread is beautiful and brings me what I want (a crispy crust, a soft crumb, a good texture and a fresh and delicate flavour), that is what it is important to me.

If in France it is usually seen as a defect it is because of our habits of a smouth crust. This comes from the fact that the French traditional method (more exactly, parisian) for the leaven bread is to work on several refreshes (minimum 3). This avoid a strong acidity and thus the blisters.
This method is not any more used because too hard (too long and too much opperations in the bread making process).
The appear of the blisters, came with the delayed proofing methods. So, it means less efforts for the baker and a modern way to produce (in opposition to the traditional way so often praised and that nobody uses anymore and even knows). Maybe is it for this reason that bakers don't like to see this on their breads. Originally, bakery is a hard job and bakers used to get a kind of pride about that. In my opinion, here is one of the reasons which incourage French bakers to try to avoid this phenomenon.
In fact, I don't think the French customer really minds about the blisters but it is a good opportunity for the suppliers to maintain this myth in the bakers' mind just to sell them some improvers with a good (very good) profit margin.




Interesting Eric,
The blistered effect here in the US is highly sought after. People go nuts trying to find out how I achieve it on my bread. I do the long cool fermentation and spraying to obtain it:




Bienvenue Eric!

votre anglais est tres clair. Ce n'est pas la peine de justifier.

avec tous votre travail comme boulanger vous aurez beaucoup de nous enseigner.

j'espere que vous trouverez des choses a apprendre aussi



That is my first post on this forum. Sorry if my English is not always perfect. Hopefully for me, my bread is better.


It is surprising and interesting for me to see this topic because the blistered crust is for us (in France) a defect and we always try to avoid it.
As said Doughman, this comes usually from a long fermentation in a cool ambiance (10°c or less) but it can be obtained shortly with a good amount of high acid leaven or sour dough (yeasted dough ; I know, this is banished here).
This effect is usually due to a high rate of fatty acid (produced by the fermentation) and to water migration phenomenons in the structure of the dough.

For the glaze, bakers usually get it with the steam injected in the oven. If you bake at home, you can put a bowl of water in your oven and drop the equivalent of 3 or 4 spoons of water on the bottom of you oven just at the loading (if you look at your loaves, you will see a kind of thin water film wich settle on them at this moment).
A convection oven is preferable to a faned oven too.




Just got the blistered effect you were after. No glaze just blisters.
Put the dough on the stone - closed the door for 1 min - sprayed top of dough - left for 3 min - sprayed again. This is as well as having a dish of water in the bottom of the oven.

you can also say "amusing" things like ,im off to feed and beat the baby!

Rolling Eyes

I guess that is better than spanking the monkey... especially after looking at all the bread porn...




Its 100% stoneground organic flour ,however it does have organic white flour in the recipe. It would be a pretty incredible loaf if it looked like that without


Thanks ,i myself am always up for a bit of horny *bling* *bling* loaf shots.

yes the babys , well its just a two day feed consistancy usualy with equal amounts water to flour ratio. we keep two "twins" in rotation for that recipe (up there) daily.
I believe its called a baby because its not yet matured into a ... mother. Its a fresh feed basicly .young! you can also say "amusing" things like ,im off to feed and beat the baby!

Rolling Eyes

thanks for the info and great bit of bread porn... as it seems to be getting referred to around the baking forums lately... fantastic looking loaf... especially considering it is a 100% wholemeal loaf...

baby method
what is this 'baby method" you refer to... not familiar with that...?

Dave above says spray water on the loaf on taking it out of the oven... and the old baker you referred to said be was doing it as it went into the oven to get the effect... now which one shall I choose... choices... choices...


anyway... thanks and cheers... will give it a go

Here is a picture of a three day ferment stoneground organic w/meal we did last night.

If you use the 2 day feed refrigerated method (mix/rest/fold/refrigerated) baby method the gluten is still strong enough to handle a 12 hour retarding .I think blistering should be sought after in recipes ,one guy i know freaked out when he saw them and he had been a baker for 10 years


spraying the loaf with water before putting it in the oven deffinatly helps to get a disirable amount of blistering.

Could be just sprayed with water when it comes out of the oven, try it.

Thanks Sasa

I knew that pretzels had something like that done to them but did not know the specifics... thanks

what I was looking for was like in the following pic that Graham has put up on this site


as there are some loaves that have very obviously had some sort of glazing done to them whereas the one is the pic is so much like several different bakeries bread that does not, at least to me, have had a glaze put on them but rather been in the baking or proofing or something???

I do suspect that something specific has been done though as it surely is far too shiny and glaze like to be a pure baking effect... but I am probably wrong on that too...


I have come sort of close but not close enough... as a home weekend baker it is just out of a curiosity and the perfectionist streak in me that is chasing this one I guess.


Hi Trevor,

Well, once you get the bread dough mixed to the right firmness, I would
let it ferment at room temperature for about 30 mins. After that, I would
shape the dough....either put it in a banneton or basket and then put it
in the cooler at 10 C and leave it there for 12 to 15 hours. The long
fermentation in the cooler will develop the flavor of the bread...providing
that you're using a starter. After the 12 or 15 hours, you can put your
bread in the oven and bake it.


Hi Trevor,

Let me stop here and be clear here. The process that I previously described should give
your bread a blister effect. However, it does not give the glaze effect...though if one were
doing this in a deck a professional bakery setting...then the steam injection in
the oven might give the bread a slight glaze effect. Giving the bread an egg wash prior
to loading it into the oven might give you the desire glaze affect along with the blisters.

From my own personal/professional baking experience that giving the bread dough a long
cool fermention will give the blister effect on the final bread product. I just want to make
sure you know this, so that I don't stir you wrong.



The blister effect can be achieved by having the bread dough go through a long fermentation.
Either in the retarder, cooler, or fridge. When I say long, I mean 12 to 15 hours in the
retarder or cooler.


Thanks Doughman

when you say "having the bread dough go through a long fermentation"... do you mean once you get the dough to the right firmness after kneading and then let it proof prior to baking... that this stage is left fot 12 to 15 hours...?

If this is the case would this not cause the dough to over-rise and thus lead to the situation where the surface of the bread bubbles up forming large pockets just unter the crust...

I would have thought that the skiny blistered "glase" as in the Sonoma example would have been made by some process like spraying the risen dough with cold water (possibly slightly salted) just prior to putting into the oven...


The blistering effect comes mainly from a long cool fermentation process. At Sonoma we do not egg wash or dip the rolls in a brine solution to create the blisters it purely comes from the long sourdough fementation and a healthy dose of steam from our oven. As far as creating this effect at home I think you will struggle to produce the blisters as a domestic ovens cannot produce the heat of a commercial oven therefore the steam created is not as intense.


Hi Jordan, Blisters on the crusts of sourdough are easily obtainable at home with a regular oven, I do it all of the time. You do need a long cool fermentation and a well cared for starter. I heat my oven to 450 and use a roasting lid over the dough for the first 15 minutes to hold in the steam from the bread. Look here on my blog: ... sourdough/

and... ... red-crust/