Home Distiller

Alright, maybe I shouldn't have had that third espresso this morning ... But I'm wondering, would adding coffee grinds to the mash make the yeastie beasties happy? It is acidic, and there's bound to be some nutrients in the beans (my wife is always telling me to put 'em in the compost pile.) Maybe the caffeine would keep the bugs up late at night, working to spin sugar into liquid gold...

dooley wrote:Alright, maybe I shouldn't have had that third espresso this morning ... But I'm wondering, would adding coffee grinds to the mash make the yeastie beasties happy? It is acidic, and there's bound to be some nutrients in the beans (my wife is always telling me to put 'em in the compost pile.) Maybe the caffeine would keep the bugs up late at night, working to spin sugar into liquid gold...

I tried putting strong neutral on a lot of coffee grounds (from the espresso machine in the coffee shop). Left it a couple of weeks.
Result; a strong and awful taste of ...Coffee GROUNDS.
Those steam machines get all the coffee flavour into the cup, there is none left in the grounds at all.
I guess you are going to have to use actual coffee if you want a flavoured drink.

As to whether yeast would like it, my guess would be, probably not. It is a lot like straw, really.
But some people boil some of the yeast from the bottom of the fermenter and say it makes a great nutrient for the yeast in the mash.

I have read mixed opinions regarding the effects of caffeine on yeast... I didn't dig deep enough to discover whether anyone had determined specific level that separated benefit from determent... I'll leave that up to individual study... Pretty sure my search phrase was "effects of caffeine on yeast"...

rad14701 wrote:I have read mixed opinions regarding the effects of caffeine on yeast... I didn't dig deep enough to discover whether anyone had determined specific level that separated benefit from determent... I'll leave that up to individual study... Pretty sure my search phrase was "effects of caffeine on yeast"...

Rad - good point! I was actually joking about the effect of caffeine on the yeast; I just assumed (there's that word again!) that the caffeine all went with the coffee, and the grinds would provide some acid and perhaps some nutrients when added to the mash along when pitching the yeast. At least it doesn't sound as disturbing as adding fertilizer! I'll follow you're lead and look for "effects of caffeine on yeast" - will at the very least be interesting reading. In practice, I'd be overjoyed I(well, at least pretty durn pleased with myself) if the grinds mitigate the need to add acid to the R.O. filtered water I'm using (well water here ain't fit to drink; OK for washing up, but sure not something you want in your home-made.)

I've got 5gal of pears fermenting right now that has two heaping tablespoons of grinds pitched with the yeast. Everything appears to be going as normal, so no ill effects. Of course, the grinds may be doing nuthing but taking up space in the bottom of the bucket. Well... I'll have fun investigating!

If we get into this a bit further, I would be interested in knowing more. I have been doing research in the exploration of the best coffee liqueur and am now experimenting with cold coffee from cold coffee beans (didn't even know there was a difference). I know that you can buy cold coffee beans and where it is grown is very important so if this path turns out to be a good avenue for nutrients then I would think having the right bean would also have an effect on the final outcome.

Bushman, what do you mean "cold coffee from cold coffee beans"? Shade grown coffee or something else?

i think he may be refering to coffee that is made for cold brewing? yes or no?

I'll step out on a limb and say "No", a central nervous system stimulant for mammals is not going to have the same effect on a fungus. Things usually must be very genetically similar for something to have the same effect. Caffeine is lethal to most bugs, for example.

As for nutrients, maybe. I avoid "Woody" things so I don't make as much methanol. I have used the last cup of coffee in the pot when making a mash. I've put damn near everything in mashes, just to use it up or try to make the yeast happy.

As for flavor, doubt it. I think of flavors like light; they are made up of a variety of scents but our noses (or tongs) only sense it as "coffee". Like we only see it as brown. But when you distill it, it's like using a prism. You only get the flavors that boil around 173*. There may be some, but whether you would recognize it as coffee is unlikely. I think the only thing I seen go into and come out of a 'still smelling the same is red wine.

I don't mean to discourage. By all means (with-in the realm of safety) experiment and please tell us all about it.

I've made coffee wine (sugar head) before - fermented like the bejuezus and tasted like crap. Triple distilled it + the crappy spiced pumpkin wine i had and it was still arse so i chucked it out.

About the only thing spent coffee grounds are good for is growing mushrooms. I wouldn't say it's even that they're a superior substrate, it's just that most people have them and they've already been sanitized with boiling water. If you want an end product to have coffee flavor, use brewed coffee or fresh ground.

Coffee wine sounds scary, though.

I don't think yeasts, or many single-celled organisms for that matter, have the necessary chemical receptors to be stimulated by caffeine like mammals are.

I visited "De Molen" micro Brewery in Bodegraven, Holland, yesterday. They add coffee to various beer recipes they have. And so - it seems - do other brewers. Now I did not like the beer that was supposed to taste like a bit of coffee that much. But at some 8% abv it certainly did not seem to have hindered the yeast doing its work ... I think the question is: can so much coffee be added to a mash that you can distill it into a coffee likker? Dunno ...

Odin.

Dunno about Coffee Grounds, but...I have put 1Tbsp of Fresh Ground Coffee in the Still with my Molasses Rum Wash & got some Wonderful Coffee Flavored Rum.

unclesarge 58 wrote:Dunno about Coffee Grounds, but...I have put 1Tbsp of Fresh Ground Coffee in the Still with my Molasses Rum Wash & got some Wonderful Coffee Flavored Rum.

How much of a charge in the still?