February 6, 2010 - 5:49pm
Yeast
I have read many times that one should use as little yeast in bread to get the job done; the job essentially being to create pockets in the dough which will serve to expand.
But, I have also read that yeast creates flavors in the dough as a by-product of its ingestion of sugars. In addition, I believe the yeast itself have flavor. A bread with a lot of yeast can taste yeasty.
My questions are:
1. does yeast provide good flavor?
2. should one strive to use as little yeast as possible?
These are somewhat critical questions but I have not been able to find answers to them in the books I have on bread.
Any insights appreciated.
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By using a small amount of yeast, it takes longer to ferment the carbohydrates and sugars,create alcohol by-products and produce enzyme action in the dough. This is what creates more flavor in the loaf.
If you use a larger amount of yeast, the dough will rise quickly and produce a loaf but it will lack the extraordinary flavor a long-fermented loaf produces.It will taste "yeasty",also.
So if you need to produce a quick loaf,use more yeast.
If you want a flavorful loaf and have the time to develop it, use small amounts of yeast.
Mix up some yeast to wet it and taste it, and please, do spit it out or suffer with deflating yourself.
Now to an answer:
1. does yeast provide good flavor?
I can tell you it smells a little nutty. But I would say, no, yeast gets the flour to ferment and that fermentation adds flavor. The fermenting taste is different from other leavening methods. Yeast leavening takes longer than say baking powder or soda. Yeast has less chemical taste than the others which can taste soapy or bitter when overdone. Fermenting happens with the use of yeast (either by introducing it or waiting for natural yeasts to come into action) fermenting gives the flavor, not the yeast.
2. should one strive to use as little yeast as possible?
yes and no, depends on how it is used
Yes, for a long ferment but one should use more yeast for flours that would break down with too long a ferment. I aim for at least a 6 hour ferment or longer.
No, if you have a dough that has fermented or wet long enough but yet appears not to have enough gas to lift the dough. Like being added to an already fermented sourdough or a long soaker. Then it would be better to add enough to get the job done quickly before the flour gluten breaks down from enzyme action.
Mini
I would just like to ask - how much yeast would be appropriate to get the 6-hour fermentation or longer (does this include just bulk-ferment or also proofing?). Is it possible to use low-yeast content for a standard method of kneading or folding (no no-knead)?
I also wonder how long and at what temperature a dough can ferment to avoid an excessive protease activity which would weeken the flour? BTW what do you mean by "flours that would break down with too long a ferment"?
Thanks!
zdenka
Six hours would be the least amount of total fermentation including all proofing. I reduce the amount of yeast in a recipe until I'm happy with it. If the rise is too fast, I cool down the dough.
Sounds like a good experiment. Low gluten and low ash flours break down faster with fermentation. At least the gluten does. That is why high ash and high gluten flours are often used for sourdoughs or long fermentations, they have more stamina, more roughage and proteins. Naturally, temperature has to be considered as higher temps speed up fermentation and so do the additions of added soakers, sprouts and such, they are also full of enzymes. Lowering the temperature and adding salt slows some enzyme activity. Check out the "Bread in 5 Min a Day" books to get some idea of yeast amounts and chilling dough for long ferments. I believe they safely push the limit.
It is always a fun thing to test the limits of a particular flour at least for me. How much ferment and flavor can one get out of the dough and still have a decent loaf and not a beer?
Mini
I use as little as is possible. Use long fermentation, preferably overnight. Have a look at some formulas on this site. I can use as litle as 6 grams for about one kilo of flour (72% hydration)
Typical no knead uses even less(a little less).