I thought I would write about this topic as it’s consuming a lot of my thoughts recently.
I have many other projects that may be more important than this which fits better in the context of land race food projects but I thought I would write about this one due to it being relatively unique.
I’ll start with some historical and cultural background:
I have recently come to the idea of breeding yeast in relation to brewing beer as we are in a time now when centuries old traditions are at the risk of extinction.
Historically when people brewed, either stone brewing with hot rocks in the stone age, or with a metal kettle if they could afford one, people would have to ferment their wort with yeast. This likely happened spontaneously with wild yeast to begin with. As people found good colonies of wild strains that they liked, then they would have saved that yeast from batch to batch - essentially cultivating an adapted colony of microorganisms, mostly yeast and perhaps some bacteria and even moulds too. Similar to seed saving and land racing perhaps?
Well, we have evidence of brewing since 13,000 years ago. Then relatively recently in the 1800’s Louis Pasteur ‘discovered’ yeast in a microbiological sense, and was able to isolate strains. Of course he didn’t discover yeast as people knew about it and saved it before but he figured out it’s function from a microbiological level. Soon after yeast has been supplied by yeast labs from isolated cultures and brewers are told you can only really brew for 10 generations at most before buying new yeast.
Brewing has been inextricably linked in many cultures globally with everyday life, with brewing being, even sometimes a mundane chore that would have do be done. With the departure from peasant life into the more modern society we have now; many cultures and centuries old traditions are dying fast. With those are the diversity of farmhouse yeast cultures that people would have kept. Yeast contributes significantly to the flavour of beer with a whole myriad of flavours that I can only imagine now as most have been lost already.
There are researchers who can this story much better than I. But I hope this gives a little context. There are countries like Norway who still have numerous farmhouse brewers who have been the custodians of centuries old yeast. Less so known brewers in other Scandinavian countries, the Baltics and Russia too. This is only a brief overview of Europe…
In the UK farmhouse yeasts are believed to have died out completely. Although I suspect they could have survived somewhat through some of our oldest commercial breweries. Much research needs to be done into this.
Most farmhouse ale recipes don’t use exact measure, but will say things like, yeast can be pitched at ‘bathwater’ temperature. Which can be assumed to be roughly 35°C. Some of the remaining Norwegian strains can tolerate 40°C and can ferment the beer in 48 hours.
Most commercial strains of yeast will ferment at perhaps 25°C maximum (without off flavours) and take between 4 and 7 days to ferment. So, what the Norwegian farmhouse strains are capable of is almost unheard of.
I suspect this is because as commercial brewing technology advanced - they could cool the wort much faster and pitch the yeast at a lower temperature and the yeast adapted to those repeated conditions over time. Losing the ability to ferment at hotter temperatures.
It’s suspected the farmhouse brewers would have been too impatient to wait longer than necessary before pitching and getting their beer!
Most of the researchers on this topic are concerned with documenting and preserving the last remaining examples of farmhouse brewing. Which is fantastic, as it’s promoting the longevity of the cultures that go with them. It may or may not be too late to preserve them, besides museums and yeast labs unfortunately…
So, this brings me to my thinking that from (at least my English perspective) anything we may have lost can be recreated. The culture could be very difficult to recreate. And we may never know what flavours they enjoyed before. But the genetics should more or less still be there. Or could be re-cultivated from the wild.
I have two ideas. Firstly, take all the commercial English strains of yeast and mix them together. Then brew small batches (1Litre) stressing the yeast to the conditions I want. Fermenting hot I will expect terrible beer and horrible off flavours. Then gen 2 I try exactly the same and if the beer improves then I know the yeast is adapting. Thus I can recreate my ‘farmhouse’ strain.
Secondly, I can cultivate and isolate wild yeast (and perhaps incorporate this into idea 1) - and try the same thing.
Then later generations I can select batches for desirable flavours/ fermentation characteristics.
I was going to write more about the genetics and the currant understanding of global yeast populations but I may save that for another day haha. I didn’t really mean to stay up and write all this but I did and I’m glad it happened! That’s where I’m at so far though…
