Re: [new_distillers] Re: Ian Smiley's "Dreaded Esters" and Fermentation Times
- jp wrote
Subject: [new_distillers] Re: Ian Smiley's "Dreaded Esters" and Fermentation Times
In Digest No. 903, Ian Smiley mentions that he would distill his corn mash
after the high krausen phase, i.e. when the vigorous fermentation has
ceased. Does it matter if there is still lots of yeast suspended in the
mash when distilling, or should one preferrably use some campden tablets to
stop fermentation and also to let the suspended yeast settle to the bottom,
before transferring to the distiller?
===========================================Ian Smiley replies:
For most stills it's quite important that there not be very much suspended yeast in the mash when transferring to the still. However, this is generally not a problem. Anyone who has made an all-grain ale will know that the mash clears very soon after high krausen. And, whiskey mash clears even faster, and for the following three main reasons:
Rye and corn mash have much less protein than a straight malted-barley mash, so there's considerably less globulins to cloud the mash;
Whiskey-yeast strains tend to be quite flocculent and settle out quickly; and
Laboratory enzymes used to complete the conversion to fermentable sugars in whiskey mashes make for very fast and very complete low-gravity fermentations, so when high krausen is finished, all fermentation is typically complete so there's no lingering fermentation to keep the mash bubbling slightly and prevent it from settling.
Unlike beer fermentations, whiskey mash clears up very quickly after the 70 to 90 hour fermentation cycle. After staining the mash, I generally let it sit for 5 to 12 hours before transferring it the still, and it's always very clear by then.