Background
Traditionally bread dough is kneaded by hand or using a mixer until the dough softens and becomes elastic. As I understand it, what takes place during the kneading is the development of elastic gluten strands in the dough. Typically bakers are instructed to knead for a given time (10 minutes is often specified), or until there is a discernible change in the elasticity of the loaf. Externally, the dough is said to be ’shiny’ or ’smooth’. It will also stretch without breaking, and one test that students are sometimes taught to apply is the ‘windowpane’ test. Stretch the dough out with one hand, and it should stretch out thin enough that you can start to see light through the dough (without breaking). This is Jack Lang’s picture of a dough that has been developed to this stage.
However ever since reading Dan Lepard’s ‘The Handmade Loaf’ I have been a convert to a different method of developing bread dough. Dan describes a method which uses only brief hand kneads interspersed with resting the dough. This allows the flour to absorb water, and amazingly the gluten strands to develop without needing to be extensively handled, molested and bashed all over the benchtop.
But are the methods equivalent? Would I have better results if I used a more traditional method of kneading? (Bill mentioned last week that he kneads his doughs unless they are very high in water content, and his pictures of a 64% hydration loaf, are much more impressive than my attempts at the same recipe…)
Aim
To determine the effect of the type (and duration) of kneading on the crumb of a simple white sourdough.
Method
As in previous weeks I used the Pane Francese recipe (I remembered the wholemeal flour this week!!). I made three 1/2 quantity loaves.
The aim was to minimize any differences between the loaves apart from the kneading method. I therefore didn’t use ‘oil’ in the kneading of loaf 1, but instead used very sparse amounts of flour.
Loaf 1:
Added starter, water, flours and salt. Mixed all together to a rough sticky mess. Covered and left for ten minutes.
Scraped the dough onto a very lightly floured surface and kneaded for just 10 seconds. Put back in the bowl, and left for 10 minutes.
Scraped out the dough, kneaded for 10 seconds. Covered and left for 10 minutes
One last knead for 10 seconds, then put back in the bowl.
Loaf 2:
Mixed starter, water, flours and salt. Tipped out onto very lightly floured work surface and kneaded (stretch, fold, turn, repeat ad nauseam) for 6 minutes, adding the least possible extra flour.
Loaf 3:
Mixed starter, water, flours and salt. Kneaded for 12 minutes adding the least possible extra flour.
All of the doughs had a proof of about 4 hours (plus a couple of hours in the fridge), were shaped, and then left outside on the balconey (overnight min temp 7 degrees) for about 9 hours.
Results
(Click on thumbnails to see a larger version)
The three loaves (1 to 3, left to right)
(~7g extra flour used in kneading)
(~20g extra flour used in kneading)
(~20g extra flour used in kneading)
Discussion
As you can see from the above pictures, all of the loaves had a somewhat eccentric oven spring, with unsightly bulges along the side or base of the loaves. I particularly associate this phenomenon with loaves that are baked from the fridge (without warming up), as I think that the oven spring is so great that the loaves won’t constrain themselves to the slashes that I make. In this case I wondered if the cool temperature outside was simply too cold to allow enough proofing (the doughs had not risen percetibly by morning).
I couldn’t tell any great difference between the loaves externally. If pressed (and perhaps I am biased) I thought that the texture of loaf 1 was perhaps superior to the 6 and 12 minute kneaded loaves. In any case the longer hand kneads certainly didn’t seem to result in an improvement in the texture of the end loaf.
One difference with traditional hand kneading is the necessity to add extra flour. In this case I was as parsimonious as I possibly could be. Dan Lepard’s method usually involves spreading a teaspoon or so of olive oil on the benchtop, and on hands to facilitate kneading. There is no need to add extra flour while kneading. In this case I added the minimum extra flour, and for loaf one this changed the overall hydration from 69% to 68%.
The other two loaves however need extra flour added to permit kneading for the longer time, and although I was as stingy as possible, I still needed to add about 20g flour (reducing the overall hydration to 65%). (Looking at last week’s experiment there was little difference between the 66% and 69% loaves, so I would not expect that to have substantially affected the end loaf)
One interesting aside. I cut into loaf one this morning before iit had cooled fully (though it had still cooled for an hour or so after baking. It is interesting to compare the texture of the cut loaf when cut while still slightly warm.
Conclusions:
Hand-kneading for 6 or 12 minutes did not result in an improved texture of a simple white sourdough loaf (in fact possibly better texture with Dan Lepard’s technique), but did result in lower hydration due to the added flour.
Replies
A really interesting post.
I rarely knead much nowadays. I think you can get decent gluten development without, although I suspect there is more tension in the gluten strands with a bit more kneading, which might affect loaf shape and oven spring.
From the look of your pictures, the loaf that was barely kneaded looks a bit "flatter", while the loaf that was kneaded most looks "rounder".
Dom, I've been using Dan Lepard's method from The Handmade loaf for most of this year, and prefer the result to the bread made following the instructions (using a 10min knead) of the people who sold me the starter.
Even when I'm making yeasted bread I use short kneads every 10 mins 3 times, then another short knead followed by 30 mins rest before proofing. I've been happy with the results.
I appreciate you posting the results of your experiment.
i think this experiment done here is very healthy. i`ll try once. thanks for posting.
kisses, <a href="http://emailextractor14.com/?page_id=98">email grabber</a>
Next time you experiment you should get an unbiased observer to taste all the breads! I would volunteer of course, since your bread looks good; the slices are a nice round shape for a nice tomato, basil and bocconcini sandwich.
Very interesting. That book is next on my list. I didn't know I was using very close to his technique.
I have developed a theory. Have no idea if it is accurate and if anyone knows better please enlighten us but here goes:
Mechanical mixing developed because commercial bakeries make large quantities of dough at a time, even artisan operations in a city, i.e. hundreds of loaves a day. Large factories probably do tens of thousands a day.
The point being that it is much larger than the 10-20 loaves that can be hand mixed at a time.
Then, commercial baking operates under the constraints of the profit motive. The less time it takes, the less cost and more profit per loaf. Simple.
If you mix dough and let it sit overnight without even one stretch and fold, there will be gluten development as the strands gradually interweave. If you have it overnight with starter it will develop more because of the movement in the dough due to the fermentation process including especially gas buildups. The movement causes the strands to come together into longer strings.
Even one stretch and fold accelerates this hugely simply by manually creating a network of long strands. Once that it done, all future development follows the tracks, as it were, of those strands.
But back to commercial baking. You are mixing up 400 loaves in one batch because you have your lovely $100,000 mixer the size of a Honda Civic. You mix the flour and water together. Well, why stop there? If you keep mixing another paltry 10 minutes, you have the same gluten development as an overnight session. And since you are using single-strain test tube yeast which produces mucho gas mucho fast, as soon as that gluten is in place, the bread will rise expansively as the gluten allows the dough to stretch out generously. Which also means not only less time but also less flour is needed since a little stretches further. More savings.
In your post you say 'traditionally' about kneading. I am beginning to wonder. I think a lot of home baking techniques these days are adapted from commercial bakers who use large machines because they bake in batch sizes too large to be done by hand. The techniques make sense in that time-is-money commercial context but they don't necessarily translate down intact to the home or artisan baker.
So my theory is this: the main value in kneading is to accelerate gluten development in order to save the time it would take naturally overnight and with a couple of stretches to get it off to a good start.
Or put another way. Kneading is only necessary in order to save time since gluten strands develop naturally given a few hours time to do so.
And then on the other hand, by giving the dough that time, you end up with far tastier bread. This is why the no-knead 'Artisan in 5 minutes a day' approach works: although using commercial single strain yeast, they give it 2-15 days in the fridge, which makes a huge difference flavour-wise. And they don't knead of course, either.
Great test!
I was taught to do 3 kneads of about 30 sec each, every 10 min for 30 min, then stretch/fold every 40 min 3 times.
I also made baguettes 3 different ways according to Professional Bread & Pastry book. The first was called a short mix, & was alot like mine above. The next was called an Intermediate mix, made with a pre-ferment the day before, & no folds & 1/2 the proove time. The last was an intensive mix, more like you would for sandwich bread. The first 2 were almost identical, & the last was like sandwich bread.
So, the texture can be great with almost no kneading & lots of time, or overnight fermenting & less time. But, lots of kneading ruins the texture & flavor.
Has any one tried the Parissiene baguette winning recipe? It have absolutely no kneading, & not much proving.
Let me know what you think:
http://www.independent.co.uk/news/world/europe/the-man-from-senegal-who-...
I can remember as a kid in the late 1950's watching the bakers mix all their dough by hand in 4 large wooden troughs about 3 - 4 metres in length.
They put the flour in the troughs followed by what I think was lard or beef dripping and water along with some of the previous days dough and I think yeast. This was mixed by hand working across the width of the trough moving back and forward along the length until a dough was formed.
This was extremely hard work and the fire wood for the oven was cut and carted after the doughs were mixed. After about 6 hours the salt was evenly distributed along the top of the now fermenting dough and this was mixed in until clear. The doughs would sit for about 6 more hours and then simply knocked back after which they would sit for I think about 2 hours before the dough was cut out of the troughs and made into whatever product s were required.
The dough maker, oven stoker would then go home and return several hours later to deliver the bread in an old Bedford van with no driver or passenger doors.
I can tell you the dough maker was the happiest man when an old Brown & Kidd dough mixer arrived along with removable bowls to which fermentation rings and covers were fitted after mixing. I think the doughs were also reduced to 6 hour fermentation.
As for kneading, it is a simple process of rearranging the protein matrix from very short tough interlinked chains to long strands of extensible but elastic predominantly gluten strands that will not only trap the CO2 produced by fermentation but expand when heat is applied in the oven to retain this CO2 resulting in oven spring without collapse. It is worth mentioning that the rapid expansion of pita breads or any flat bread baked in a very hot environment has a lot more to do with moisture being converted to steam where the dough in contact with extreme heat seals, forming a skin like a football bladder which blows up as the steam is generated. Turn down the heat and you basically turn a pita into a naan.
The protein change is known in the science world as disulphide - sulphydril interchange which can be web searched if interested.
Protein development can be achieved either by mechanical, chemical or physical (fermentation) means or a combination of either. Most sourdoughs in domestic or non commercial situations are slightly mechanically developed by hand or machine and the bulk of the conditioning occurs during fermentation. Simply, the better or more thoroughly the protein is developed in a moderately hydrated dough that is presented to the oven in peak condition the finer the crumb structure and the brighter the crumb. This transfers to the crust as smoother and more reflective and the break will exhibit very fine strands with very little sign of breakage or severe tearing.
Generally to achieve a more open crumb you need more hydration and to adopt a process that preserves as much of the gas in coalesced cells as possible. In other words you still need a well conditioned dough to maintain a nice crumb structure and if you want the large holed open texture do not knock the gas out during final shaping.
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