I've been brewing mead and beer for some time now, so I'm embarrassed to be asking such a stupid question, but what exactly causes fermentation to cease in beer?
I'm aware that different strains of yeast have different alcohol tolerances, and will die when the alcohol level reaches their tolerance, but my understanding is that most beer yeast strains' tolerances are far above what most beers make it to (10-11% range).
I'm also aware that if the wort were to run out of sugar, that would also cease fermentation.
But neither of those limitations were reached with a recent scotch ale I brewed, that made it to probably 6.5% ABV and was still VERY sweet. Why did fermentation stop, when there was plenty of sugar left to ferment, and the beer hadn't even come close to the alcohol tolerance of the yeast?
Thank you for your help,
Brian
I'm aware that different strains of yeast have different alcohol tolerances, and will die when the alcohol level reaches their tolerance, but my understanding is that most beer yeast strains' tolerances are far above what most beers make it to (10-11% range).
I'm also aware that if the wort were to run out of sugar, that would also cease fermentation.
But neither of those limitations were reached with a recent scotch ale I brewed, that made it to probably 6.5% ABV and was still VERY sweet. Why did fermentation stop, when there was plenty of sugar left to ferment, and the beer hadn't even come close to the alcohol tolerance of the yeast?
Thank you for your help,
Brian