What were we talking about yesterday? Ah, yes. Yeast. ‘Member? 1)Don’t be afraid of the yeast. 2)Keep the yeast at a comfortable temperature. You know, so it won’t DIE. 3)Use high-protein flour. 4)Yeast lives to turn sugar into alcohol+carbon dioxide+heat. Now, we’re all up to speed. Before we launch into Part Deux Proper, there was a question from the floor: Donna asked, “Let’s say, hypothetically of course, that your fast acting yeast accidentally ended up in the fridge after coming home from the store. Is it still ok to use?” The short answer is, “Don’t worry; you’ll be fine. So will the yeast.” Then, there was this comment: Meryl reminded us to make sure the yeast isn’t old. Sage advice Meryl. So, while putting the yeast in the fridge ( hypothetically) won’t hurt it, if the yeast is beyond its expiration date, or it doesn’t bubble when you try and proof it, you’ll have to pitch it.
There are about 1500 different kinds of yeast. That’s a Very Lot. Not all of them are the kinds that we want in our bread or our beer, though. Here’s the kind we like: Saccharomyces cerevisiae Look at those words for a second–I see “sugar” and “beer.” Those crafty yeast-namers! S.cerevisiae eats sugar to make alcohol. Perfect.
So, Tell Us, When Did Folks Start Putting Yeast in Bread?
Nobody really knows when people started actively using yeast to leaven their bread. There are records of bakeries back in ancient Egypt, but nobody can really pinpoint the date. Best guess–about 5000 years ago.
How Did It Happen?
Oh, hooray–story time! Mr. Retehtey (Egyptian for ‘baker’–see, I do my research) mixed his flour and water as usual. Then, his wife called to remind him of the parent-teacher conference (okay, not too much research). Since family duties take precedence over bakerly duties, off Mr. Retehtey went to the conference. We shan’t eavesdrop there, but suffice to say, it was a long conference. When he returned to his dough, he noticed that it was puffy and smelled interesting. Not bad–actually, it smelled pretty good. With a shrug and a quick prayer, Mr. Retehtey baked his dough, and what came out was remarkable! Puffy, sproingy, golden brown bread. Yay for you, Mr. Retehtey!
Setting out the flour and water was an open invitation for yeast to jump in and chow down. Free carbs! Happily for Mr. Retehtey, and for us, old S. Cerevisiae, or a close cousin, showed up.
These days, there are a couple of options for replicating Mr. Retehtey’s feat. You can harness your own wild yeast and hope for the best, or you can buy a sourdough starter (a mix of several strains of wild, tasty yeast that provide a tangy, slightly sour flavor profile). Sourdoughs are not my forte, so I won’t even try and pretend to be The Expert. There are plenty of sites out in the vast Hinternet that can help you with sourdoughs.
I have much more experience using fresh and packaged dry yeast. Fresh yeast is sold in compressed cakes. It is soft, somewhat sticky, and highly perishable. If you are using fresh yeast, you must keep it well-wrapped and refrigerated and use it within a week or two. For that reason, it can be a bit of a pain to use, especially if you don’t bake bread very frequently. I used it at the restaurants I’ve worked in, but at home, I stick with the dry kind.
The two most commonly available types of dry yeast are Active Dry and Rapid Rise. Active Dry yeast comes in fairly large granules and generally needs to be dissolved in warm liquid before using. Rapid Rise yeast is processed into finer particles and was developed to be added along with all the other ingredients–no dissolving required. In recipes calling for fresh yeast, I usually use 1/3 the amount of dry yeast. So, if a recipe wants 1 oz. fresh yeast, I’ll use 1/3 oz (about 9-10 gram) of dry yeast.
Store you dry yeast, tightly sealed, in the refrigerator or freezer. It will last up to a year, so if you’re uncertain, do the proofing trick to make sure your yeasts are still alive and kicking.
And that, my friends, concludes this episode. Tune in for the exciting conclusion tomorrow. If you have any questions, please comment, and I will address them post haste.