[quote]French brewing engineer Georges Lacambre gave a description of it in 1851:
It was brewed year-round (except in extreme heat)
For one hectolitre of beer, one needed 36 to 38 kg of lightly amber malt, 500 grams of good German hops and 35 ml of yeast
Like the beer of Paris and Lille, it was boiled for 8 to 10 hours, and fermented for 3 to 4 days
It contained 5% to 6.4% ABV
It was dark amber in colour, had a very agreeable taste, it was mellow, strong and hoppy
In Lyon, it was drunk four to five weeks after brewing
The export variety was brewed only in winter and drunk only after four to five months (like the bière de garde of Strasbourg, Lille and Paris).
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So it was 100% “lightly amber malt”, enough for 1.050 - 1.060 OG, assuming average-ish attenuation. No idea what would be in modern ingredients.
Maybe use some caramel malts to simulate a longer boil? 8-10 hour boils are not feasible for me right now.
Enough German hops to be “hoppy”. Maybe 30-50 IBUs?
I’m assuming a mild ale yeast since no mention is made of yeast character. Or maybe something reliably uncharacterful like 34/70.
Well if you divide by 5 to get a first approximation (ie 20 litres, 5.3 US gallons) then you get
7.4kg (16.3lb) ??Munich?? (probably need less than that, as their efficiencies/extract will have been lower than nowadays)
2% melanoidin malt??
100g of Spalt or something (even Strisselspalt, Alsace counted as German at various times in history)
7ml (1.4 US tsp) of yeast
The fact they were brewing year-round in Lyon suggests they had a fairly heat tolerant yeast - probably not a lager yeast.
As you say, no mention of notable yeast flavour but all that maltiness could hide quite a lot, maybe something like T-58?
Given that it was brewed year-round, it seems like it would have been an ale yeast of some sort. But I can’t find much about yeast character for that region of France or the adjacent parts of Switzerland.
Why do you assume a more neutral yeast would be more appropriate?
And to be honest - T-58 is pretty neutral, it’s only weakly phenolic. As such it is actually closer to a lot of commercial British ale yeasts - but people who only know the Wyeast and White Labs catalogues think that British yeast are always non-phenolic.
And given that we’re going back in history and are guessing, then some phenolics are more likely than not, losing phenolics is one of the characteristics of domestication.
Yes, it’s possible that they had a non-phenolic yeast, there is a possibility that it was a kolsch/alt type of yeast - but equally it could have been a biere de garde kind of yeast, even a wine yeast.
We don’t know - which is why I went for something kind of in the middle. I don’t think WLP029 would be appropriate, given that it is a lager yeast.