The Fresh Loaf

News & Information for Amateur Bakers and Artisan Bread Enthusiasts

Another question on yeast.

naltoidaddict's picture

Another question on yeast.

My father made a decent living baking bread for a number of years at a breakfast joint in Jamaica and taught me everything I know about baking bread, which, admittedly I don't know much about. He always told me to "prime" the yeast in a pint glass of warm water with a pinch of sugar before mixing. This is something I do religiously any time I make bread and it seems to help (also helps me know if the yeast I'm using is still alive!). But quite honestly I really haven't been terribly impressed with any bread I've ever baked. What I make isn't bad or inedible but it always seemed to be missing a good deal of texture and flavor that's present in many of the breads I like.

The recent nytimes article prompted my girlfriend and I to start making bread more like mad. Our proof on concept baking was pretty good. We followed the recipe exactly, I even went out and bought a dutch oven, though all our local cooking supply place had was a Rachel Ray's branded type. Though it drove me nuts to wait that long to put it in the over I was delighted with the texture we ended up with.

Anyway, my question,

During the rising process does the yeast kill itself eventually? I mean, if I let it rise for such a long time do I have give it a breath of fresh air occasionally? Does it ever eat all the sugar and then just go dormant? And what's the max time you should let something sit at room temp?



Breadwhiner's picture

One thing that can kill yeast in a food process is too much alcohol. That's why wine only has 6% alcohol-- above that the yeast die and no more alcohol is produced. I can't think of a situation wherein yeast would go dormant in dough, however, because it is hard to get enough alcohol in dough to kill the yeast.

You will know right away if you have let the yeast sit too long-- your dough will smell like, you guessed it...alcohol. Doughs that have added sugar are especially lialbe to this but eventually just about any dough can go alcoholic.

I have cooked several alcoholic doughs and the main problem is that they have a harsh aroma. Along with high alcohol, these breads tend to have very low sugar, even natural sugar, as the yeast have eaten all the sugar to make alchohol.

Eventually, the alcohol will evaporate from a bread made from alcholic dough, but my recommendation is simply to avoid this situation. When you want a long rise, make sure to restrict the amount of yeast or cut back on the temperature. For long rises, you almost always want to have a lean dough (flour, water, salt only).

The priming that you are talking about is necessary with active dry yeast. Since your father's time, instant yeast has been developed. You can add instant yeast right to flour. People who bake a lot of bread tend to use instant yeast.

Good luck in your bread baking adventures.



popthebaker's picture

Re: Breadwhiner “One thing that can kill yeast in a food process is too much alcohol. That's why wine only has 6% alcohol-- above that the yeast die and no more alcohol is produced.” Wine can vary from around 10% to 14% alcohol depending upon the variety of yeast used. There is no one wine yeast but many different types and some, such as Tokay yeast, can produce even higher alcohol levels in wine. There is not enough fermentable substrate available in an average bread dough, lean or enriched, to produce enough alcohol to kill the yeast in the time it takes to complete the fermentation process. “The priming that you are talking about is necessary with active dry yeast.” Please don’t tell my jar of active dry yeast that it has been working just fine for two decades when added directly to dry ingredients followed by the wet ingredients. Priming, or proofing, is a hold over from the days of cake yeast when it was not a sure thing that it would work. I routinely make direct dough as well as preferments with active dry yeast without the process of priming. Also, I do bake a lot of bread and continue to use active dry yeast with, judging from comments by those who consume it, some degree of success.Pop

Floydm's picture

Eventually, yeah, the yeast can run out of food. But small quantities of yeast like the NY Times article mention can go a looong time.

I don't think there is a clear cut max time. It really depends on the quantity of yeast being used, the size of the batch, the room temperature, etc.

Active dry yeast has to be activated in water. Instant yeast can typically just be thrown in with the rest of your ingredients and it'll go to work.

UnConundrum's picture

When you see the fermenting dough start to fall back just a little, that's the yeast telling you it's time to move on because most of the sugar they feed on has been consumed.  

jillhodges's picture

Bread can definitely be over-proofed. If you want a longer proof, you can stick it in the fridge to slow it down. Otherwise, you have to add more yeast on the second puff. I think that the La Brea bread book explores the long proof and may even only use that fridge-slow proof.

 A slower proof gives you more flavour.  It also allows you to use less yeast.  Less yeast means that the bread will go stale slower, so a slow-proof bread is generally considered a superior bread, as I understand it.



naltoidaddict's picture

Good stuff!


thanks all