Yeast is still a scarce commodity, at least in the forms used for baking. Brewer’s yeast though may be a different story. I checked the website of a home brewing store that I used when I was learning to make soda (aka pop) and cider while living in Milwaukee WI (Northern Brewer), and they appear to have various types of yeast in stock for beer and ale brewing, cider brewing, and wine as well. While it’s likely true that there are fewer people looking to start brewing than baking right now since there is considerable more investment in time, equipment, and ingredients, the fact remains that yeast is apparently available for this purpose, and for not hugely inflated prices. Side-note/ for the record: the difference between ale and beer is that beer requires the use of hops, while ale does not.
This got me thinking about the medieval processes for such products as compared to bread. With bread baking, the basic recipes and procedures have not changed a lot over the centuries. While certain modern inventions like electric ovens, different forms of yeast and flour, as well as a greater variety of loaf types have updated how we bake today, bread baking has not changed fundamentally as a key food product which is made from flour, yeast, salt, and water, and baked.
As with last time, I’m operating with limited scholarly resources but here’s what I’m figuring: in fact there are some significant differences in the recipes and methods used for brewing between medieval Europe and today. Ale was likely the more common beverage, and probably more nutritious as well, so we’ll go with that as a base for comparison. Beers and ales are also considerably older than the medieval period, but since the opening comparison was with medieval bread, again, that’s what I’m sticking with; although, bread itself is likewise much older than Medieval Europe.
So, first the ingredients. Ale requires water, yeast, and malted grain (probably oats or barley in the Middle Ages). Malting refers to a process involving soaking then drying the grain, and partially crushing it. The basic process involves boiling the malt and any additional grain and flavoring (like honey, herbs, roots, etc.), letting it ferment, adding the yeast, and letting it further ferment. Straining the resulting brew a few times would likely be required before drinking. The whole process from start to drink probably took about a week. Recipes and procedure from aristocratic and religious orders survive from about the 13th century onwards, although older recipes do survive from previous time periods.
On the modern side, the process and ingredients differ substantially, as does the terminology. The modern recipe I’m referring to includes two items not present in the medieval recipes: sugar and hops. This would technically make it a beer, so that’s a major change there, that beer and ale are now more interchangeable as terms to the modern brewer. “Beer” now generally means a drink brewed using fermented grain, leaving the distinctions to be made between types of method and ingredients. For example, ale is made with top fermenting yeast and brewed with heat, while lager uses a bottom fermenting yeast brewed at lower temperatures over a longer period of time. The modern recipe starts much like the medieval in that it requires boiling and fermenting of the malt, grain and any additional flavorings, and later adding yeast. However, after the first week, there are additional process and time. The ale is not ready for further processing (bottling) until about the end of week 2, and once sealed in its bottle, the ale needs another few weeks before drinking. This process represents some significant difference, not even considering the substantial differences in the types of equipment likely used, not limited to but including the modern hydrometer.
There are some steps I’m not considering individually such as the lowering and raising of the temperature during the initial cooking/boiling stage in the modern recipe, and the additions of certain amounts of water followed by resting done in stages in the medieval recipe. These elements are similar in both time frames and the exact details would differ from individual recipe and batch, especially in the medieval versions. It’s also worth noting that one possible procedural element in the Middle Ages, that of storage, is not being factored here. Ales (and beers) certainly could be, and would have been, stored in medieval Europe, and apparently thanks to someone paying attention to what happened to the ale or beer during the winter and realizing that the product kept up some fermentation even at the colder temperatures, this led to what we now call “lager”. Also worth noting, the yeast used in these processes would most likely have been used a second time in bread baking.
I remember a few years ago at a medieval academic conference, there was a social hour during which beer brewed according to medieval methods and recipe, and using the medieval ingredients (or as close as is possible), was served. I don’t remember the details but I do remember thinking that one of the samples was fairly weak tasting, and neither of the two I tried had the level of carbonation most modern beverages of similar sort might contain. Granted, modern technology includes the use of CO2 infusers and other ways to measure and control that factor, but I was still a little surprised. I know for a fact that brewing exclusively with yeast can result in some powerfully fizzy drinks, since in the past I have tried brewing my own cola and root beer. Interestingly, the Middle Ages and later eras had similar types of drinks. Brewed beverages made from herbs and spices (and/or maybe fruit) that were lower in alcohol were called “small beers” by the Renaissance, and references and recipes for such things survive from at least the eleventh century, the time St. Arnold.
So overall, it seems that beer is more complex in its history which may be why it’s so much more different now than it was in past centuries. Unlike bread, where the basics have not changed much, fermented brewed beverages not only varied more over time, they also have more varied history and language associated with them. These two features are probably related.
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