Cold brew coffee fermentation?

[damiongrimm]

I’ve made cold brew coffee, and had been thinking about making 5 gal and putting it on nitro. I saw a post about someone that put cold brew coffee, chocolate syrup, cream, and everclear into a keg on nitro and made a “kickass mocha” on tap.

This got my gears turning a bit.

How would be the best way to go about making a fermented coffee “beer”?

My thought is this: if I take 5gal of cold brew coffee, lactose, and enough sugar(probably table sugar or fructose, for how clean they ferment) to bring the gravity up to around 1.080-1.090 (aiming for around 8-9%abv) then Ferment down to about 1.020. I was thinking about using Darkness yeast from Imperial, for the rich chocolatey and earthy notes it imparts. I’m hoping for as close to an adult iced coffee as I would be able to get.

thoughts? Opinions?

 

[NGD]

I would do a small 1 gal test batch. Its either going to be amazing or taste as if you wont want coffee for awhile.

I’m assuming your banking on the bitterness from the coffee to offset the sweetness from lactose? Could lead to something interesting.

 

[damiongrimm]

haha that’s fair. Yes that’s exactly what I had in mind was that the bitterness would balance out the lactose. A gallon test batch might not be a bad idea with what I’m seeing so far. My curiosity though is would it be better to boil up a sugar wash and ferment that, then add coffee at keg off, or would using cold brew coffee As “brew water” then adding simple syrup along with a campden tablet to that, then pitch? Do you think the coffee would develop any flavors during fermentation being in such a large amount?

 

[NGD]

Seems like if you used a sugar wash as a base, that would be similar to adding coffee to a hard seltzer base. It would ferment dry and the bitterness from the coffee would be up front and present. Coldbrew might work better. Still seems like it would lack much body even with the lactose.

I’m not use if using coffee as a base for fermentation would work due to other compounds present in coffee. Seems like theres a high chance of undesired ester production or reduced fermentation in the presence of polyphenols. Namely what effect would chlorogenic acid have during the fermentation cycle. With that said, I’m always down for people trying new things.

Hell if you told me 10 years ago that hard kombucha was going to be a hit; I would have looked you dead in the eye and asked “what is kombucha?”.