An experiment: a more vs. less open crumb

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I wanted to see how kneading time can affect the openness of the crumb.

My hypothesis is longer and vigorous kneading will contribute to less open crumb, holding everything else equal.

Using the same starter, same recipe, formula, weight, tools, etc., the only difference was the kneading part (and the number of stretch and folds).

Recipe was adapted from the Perfect Loaf (https://www.theperfectloaf.com/sprouted-buckwheat-sourdough/), but I made a few modifications.

I substituted half dark rye flour and half barley flour for buckwheat flour; cracked wheats, rye chops, and rolled oats for buckwheat groats. Following the two-hour autolyse, I kneaded the doughs separately two ways. Bulk fermentation lasted for four hours, and rested at room temperature for an hour after shaping before putting in the fridge.

I lowered the hydration level to 82% because I was not confident in handling high hydration doughs.

1. Slap and fold lightly by hand for 12 minutes. Coil fold during bulk fermentation 4 times.

 

2. Kneading by hand (slap and fold) vigorously for 25 minutes. Stretch and fold during bulk fermentation 3 times. 

 

Compared to the dough from the first experiment (less kneading), the second batch was more workable and stronger. After the second stretch and fold, I felt it was almost impossible to do another (did it anyway). 

Although I tried my best to control for the factors other than kneading, I accidentally left the bread (#2) in the oven few minutes longer that I burnt the bread. 

Overall, I liked the less opened crumb (#2) better. The crumb was so soft and moist. I don't fully understand but I think it was tastier and had more flavor than the open-crumb one (#1). It was a fun experiment!

Next time, I will try to use different autolyse duration to see how it affects the crumb.

 

 

Fondue, thanks for posting your experiment. It is nice to learn from the efforts of others.

I noticed that the heavily kneaded dough appeared to be baked much hotter. I say this because of the deep browning on the crust. My latest experiments lead me to believe that premature browning of the crust will prevent further oven spring while at the same time hurting the ear. Once the crust hardens, it is unable to allow expansion. This will cause the crumb to remain tighter. Do you think this may have affected the crumb of the heavily kneaded dough?

My present belief is that well developed gluten makes a stronger dough. Stronger dough makes it more difficult for the individual cells (alveoli, bubbles) to expand. The opposite is true of doughs with weaker gluten. Weaker doughs require more gentle handling for that same reason.

What do you think?

An example of the above paragraph can be seen here. http://www.thefreshloaf.com/node/61659/ear-bloom-and-oven-spring-skin-deep-beauty#AnchorText1

Please don’t consider this reply critical. I know how much work experiments can be. I do think that the commonly accepted belief, that more kneading produces more uniform crumb, is true. Sandwich bread is thoroughly mixed to completely develop the gluten.

My preferred crumb is the dough that was kneaded more. It appears to have been well shaped.

Keep posting those experiments. I am eager to learn.

Danny

 

Hi Danny,

Thanks for sharing the post! I learned a lot from your reply and your experiment.

I think you are correct about the crust of the heavily kneaded one. I thought I burnt the crust because I left the bread about 7 minutes longer in the oven (without steam) but now I'm contemplating a few possibilities: higher temperature of the oven, hotter dutch oven, duration of preheating, and etc. Those are the things I totally ignored in this experiment. 

Now I understand that a combination of minimal kneading and lower oven temperature could have contributed to an irregular, open crumb. Likewise, higher temperature can prevent the dough from blooming in the oven by hardening the crust early, which explains the crust and the smaller holes in the heavily kneaded one.

Thanks for helping me to solve bread mysteries!

 

Fondue, if your bread cooked 7 minutes longer, my thought is probably not valid. That could mean that both doughs rec’d the same amount of heat during the initial portion of the bake. Oven spring, bloom, and ears all take place in the beginning of the bake. If the crust browned because it was baked longer, no hotter, then disregard my first post.

If the above is the case, your experiment appears to be accurate.

I hope others weigh in on this. The more input, the better.

Danny

This principle holds for gluten free bread also.  I remember hearing some grumbling about a year ago on Twitter about how Celiacs should just "get used to" the open holes in GF bread, which still is a significant problem.  And many gluten free baking instructions only advise a single rise with no second rise at all because vaguely, "It damages the loaf."  Once one person says this in a blog post it tends to get repeated by others.  So I was determined to ignore it and see what happens.  I've never had a "hole" in a sandwich bread if I used a gentle knead / second rise.  And if I just knead/rise and then bake, the crumb can be quite fluffy and more open, but often has a space/bubble/hole at the top.

Like this, no gluten, dough cycle and then bake in a bread machine.  Note the deflated "hole" at the top. Recipe

I've never tested a long vigorous knead though.  I'd have to use the mixer, I'm not strong enough right now to do it manually. But it's something to be curious about.

The perfect evenness of commercial bread is probably due to high intensity mixing (ref http://www.flourandwater.co.uk/FlourandWater.pdf  page 16, the CBP).  That process caught my attention because it's appropriate for low gluten bread, but the mixing also hints that the starches are more broken down by mechanical means while, like Dan said, the gluten present is fully developed.

Manipulation might lead to evenness in any raised dough.

It's possible it might moisten the crumb if more manipulation is used. I've had a run of "too moist" results which might be explained by starches picking up more water due to more mixing.   But I'd be guessing.

The best bread I've had (in now 74 years) where huge bauernbrot loaves in Heidelberg.  That bread had a moderately open crumb, tighter than the bubbly jelly-drippers I get from high hydration recipes.

I've experimented with lower hydration and with more kneading.  I've been getting the crumb results I wanted but so with without enough rise.