Hot fermentation

[Rocky_Creek]

I am doing my first fermentation out in my shop next to the still, it's hot as hell in Georgia right now. Previously I fermented in the basement where it's nice and cool. This fermentation is running way hot, I'm using distillers yeast. We'll see what happens. Fermenting corn, rye and a lot of sugar. I'll let you know what I learn.

[LeftLaneCruiser]

We'll be curious.

From experience i can say that a hot and fast fermentation is not the best.
Sure it goes fast, but it will be incomplete (leftover sugars) and have more off-flavour than a slow, cool, fermentation.

But keep us informed...

KJH

[Brett]

hot fermentin creates more of the nasty n off flavoured alcohols

[Tater]

The distillers yeast does well in warmer temps

[Brett]

quotes from homedistiller

Fusel oil concentration in the wash can be up to around 0.24 g per Litre from 20% sugar (eg about 3.2 mL from a 20L wash)

Fusels increase depending on ...
* yeast strain (eg Saccharomysce cerevisia makes more than S.carlsbergensis)
* temperature (higher temp = more fusels)
* increased aeration and agitation (news to me ! so don't over-stirr it !)
* wort composition (nitrogen sources and readily metabolised sugars)

The temperature the yeast is used at also can cause the flavor to degrade. Most whiskey mashes use an ale yeast- the ideal temperature range is 60 to 70 degrees F. Lower temps will slow down the yeast- if sanitation is good- this is not a problem. If a higher temp is reached - the yeast will undergo "stress" reactions that cause excessive ester and higher alcohol formation- this will result in a solvent- like flavor that can carry over into the finished spirit.

Temperature control is very important during fermentation. Yeast is a living organism, and will die if too stressed. Both alcohol and temperature stress it. With no alcohol around, it won't die until about 40 &degC. At 14% alcohol, it will die at 33 &degC, and at 25 &degC if in 20% alcohol. So keep it below 25 &degC at ALL times. Lower temperatures will also result in less volitiles. When the temperature has been kept below 30 &degC the production of fusel oils is minimal, and is extremely small if kept below a maximum of 25 &degC. This is where you get into a bit of a trade-off; if you keep it too cool, it will take heaps longer, with greater time for the risk of infection etc to set in. At 25 &degC, it will take 3 days to ferment 0.24 kg/L sugar, but at 15 &degC it will take nearly 2 weeks.

Higher fermentation temperatures will result in more fusels being formed

[Rocky_Creek]

Tater is correct, there were no ill effects with distillers yeast and a hot fermentation.

[outlawokie]

Awe this is great to i have been strugling with bakers yeast and the heat i have a couple of gallons that i am going to use some carbon on to make mixing hooch