Transcript of Video:
As we continue our series on 18th century breads, we feel we’ve only just begun to discover that complex role bread plays in history. Today we’ll take a closer look at leaven in the 18th century, how to preserve it and then how to use it.
First, we need to make a distinction between the word leavening and the word leaven. The word leavening is a generic term meaning anything that you add to dough that creates a lighter and fluffier loaf when you’re finished. Leavening can be mechanical. We can whip air into egg whites, creating a meringue that we fold into batter to make a lighter bread. We could also use a chemical agent such as pearl ash or saleratus similar to the modern baking soda and baking powder. These create a chemical reaction. Carbon dioxide bubbles are formed and this creates a quick bread, a lighter and fluffier sort of bread. Then there’s yeast, which is a biological agent. The word leaven, at least in the 18th century, means a lump of old dough.
We know from archeological evidence that yeast has been used for thousands of years for brewing beer and for baking bread. By the mid 1700’s, two strains of yeast had been domesticated, ale yeast used for brewing beer and for baking bread and lager yeasts which the Germans had developed for brewing beer at cooler temperatures for longer periods of time.
By the late 18th century, ale yeast had been further refined by the Dutch for commercial sale, specifically to bakers. Now while modern commercial baking yeasts have been cultivated into various strains, they still remain the same species of ale yeast.
Now there’s a third species of yeast we have yet to mention. That’s wild yeast. Wild yeast exists everywhere. It exists in the air, on your skin, even on the grains of wheat themselves.
Many 18th century bread recipes call for the use of barm, which is that soupy yeast mixture that’s skimmed off the top of a fresh batch of ale. In our mixed bread episode, we showed you how to make a modern equivalent to barm. For the British palate, barm was the preferred form of yeast. They like this lighter sweeter bread. In fact there were laws passed that prevented professional bakers from recycling or reusing they’re yeast, this old dough, which resulted in a much sharper flavor. In contrast to the British, up until 1670, the French outlawed the use of barm yeast in making bread in favor of the much more flavorful and acidic old dough or leaven method.
We talked about our generic term of leavening and the term leaven which means old dough. After our initial batch of bread dough is yeasted, we save back a piece of this dough for our next batch, whether it’s the next day or the next week, and as this process continues, each time we make the dough, we save some back for the next batch, it turns into what we call sourdough, but I’ll explain that more in a minute.
Now, there were many reasons to use this old dough or leaven. The first one was flavor. It gave a much more rich and sharper flavor to the bread, but there were other reasons also. Not only in France, but in Great Britain and America, because of the importance of ale in the 18th century diet, virtually everyone had access to ale yeast or barm, but there were circumstances when the supplies were very limited. Take for instance, William Ellis who wrote the 1750 book Country Housewife Family Companion, and in it he mentions a shortage of yeast during the great frost of 1740. This year marked the coldest period during what is now known as the little ice age. Yeast was very scarce during that time in Europe because of the extended period of frigid temperatures that prevented it from being cultivated.
When barm was in short supply, leaven was used to replace it, but there was another reason to use leaven and that was to preserve yeast from one session to the next. Frequent use of a wood fired oven was impractical and inefficient for the home baker so there needed to be a way to preserve yeast from one baking session to the next.
Now we have to remember that in the 18th century, no one fully understood yeast, what it was and how it worked, any of these things. It wasn’t until the mid-1800’s that yeast was proven to be a living organism. Now the difference in taste between bread made with barm and that made with leaven has a lot more to do with bacteria than it does with the yeast that’s involved. Bacteria lives along with yeast inside of every ball of dough. It converts sugars that are in the dough into lactic acid, so if you let your dough ferment long enough, it doesn’t matter whether you start with a wild yeast culture or a barm, your dough will begin to sour. It’ll begin to take on those characteristics of sourdough bread and so your dough may not taste exactly the same as some regionally famous sourdough breads, it will be a sourdough bread nonetheless.
For the first part of our demonstration today we’re going to make a very simple bread dough. I’ve got four cups of simple bread flour here, unbleached, and I’m going to add to that just a teaspoon of kosher salt, and now I’ve got some yeast. I could mix up barm, but since this isn’t really the main part of what we’re doing here, this is just a start, we’re going to use dry instant yeast. It’ll end up being exactly the same in the end so that’s what we’re going to use here. So we’re going to use a packet of instant yeast.
And now we’re going to add to that about a cup and a half of warm water, make a pool here.
This should make just about the right consistency.
Now we’ve got this mixed, let’s turn this dough out onto a floured surface here and we’ll get that mixed up, and we’ll knead this until its ready, until it’s nice and soft.
Okay, this dough is ready to let it set and rise, but now’s the time, I’m going to extract a piece of dough to use for the next time I’m going to bake bread, so here we go, here’s a piece of dough, we’re going to save this for later. And we’re going to take this, reform it up into our shape, let’s put it in the dough bowl and let it set for baking. We’ll let this set an hour or two and then we’ll bake it in our oven.
Now here’s our dough that we’ve taken off for the next baking. If we’re going to use this dough tomorrow or if we’re going to use it maybe the day after, we can just take this ball and put it into a little pile of flour and save that for later on, but if we aren’t going to bake for 7 days or 10 days, we need a way to preserve this for later use, so what we can do is we can store that in some salt. To preserve this properly, what we’re going to do is we’re going to punch a hole in our dough, we’re going to take that and fill the hole with salt so that it’s got salt in the middle of it and once this is salted we’re going to make a little cavity in our salt canister and we’re going to pour salt right on top and fill that up so it’s covered up with salt and this’ll dry out. It’ll be a little hard lump when it comes out of here in a week or 10 days.
In our next episode we’re going to take this preserved dough ball and we’re going to wake it back up and we’re going to use it to bake some bread. We’re also going to start a wild yeast culture.
Be sure to subscribe to our YouTube Channel and check out our Facebook page for all the news at Jas. Townsend and Son. All of the items you’ve seen here today, all the cooking implements, all the clothing, these things are available on our website or in our print catalog and I want to thank you for joining us today and I want to invite you to join us as we savor the aromas and flavors of the 18th century.