I have dealt with medicinal flavor beers quite often. Too often than i would like.
Still, i have narrowed it down to some culprit, but still find it hard to avoid.
Some Yeasts are more prone to stress than others. This is a known fact that i learned for myseld too. I have had stressed yeast off flavors from WY3068 and WY3787. Until now, none of my DRY yeasts have showed medicinal flavors due to stress.
I have used : 34/70, US-05 , Nottingham , Belle Saison and S04
Last year i made 2 Dark Saisons (i know, not true to style) with the Belle Saison yeast.
They came out close to 9% ABV due to extremely attenuative yeast ( did not know it well yet) and very highly pronounced fusel alcohols that blamed to temperatures (fermentation was 26ºC ambient ...probably rised above 30ºC in vessel).
This time, decided to brew a "classic Saison" , light Pale in color and lots of Amarillo. Kind of like a Boulevard Tank 7 (followed a recipe for that).
Everything in mash went well, and i cooled down 21L of beautifull clear wort to my fermenter.
Error nº1 : I forgot to aerate the wort.
Error nº2 : Used 1 packet of Belle Saison (1 year old in the fridge) properly hydrated
Maybe because it was not aerated. Maybe because it was old yeast and not enough yeast for a 1.065 wort. Still it lift off fermentation in 12h....and fermented vigorously for 2 weeks, dropping down to 1.006. Temp was controled at 20ºC steady during fermentation.
Problem : medicinal taste. terrible again.
I know this off taste, it is stressed yeast. It is NOT due to chlorines, i have treated water.
I just cant seem to understand, because lots of folks seem to use this yeast underpitched. They also seem to go higher temps, i thought i would keep it low, to prevent off flavors. Guess not.
Anyone else got medicine from Belle Saison ?
I guess i will try this again, but need to know what to change ...
Cheers