This thread https://www.homebrewtalk.com/f164/s...-enzymes-lot-interesting-possibilites-210086/
lead to more reading. Sweet potatoes have amylase (alpha and beta) in them, and a fair amount of starch. In africa, adding ground sweet potatoes to the sorgum mash significantly improved yields in beer making.
So this afternoons experiment:
2.5 pounds grated sweet potato (including skins)
2 gallons water at 150 F
Mashed for 90 minutes, did a single decoction (see note below)
Ended up with 1 1/2 gallons at sg 1.015
1 hour boil with 1/4 oz fuggles. to 3/4 gal and sg at end of boil 1.030
Will pitch s-05 (its what I have) when it cools. Not sure if this will even be drinkable, but the science is fun!
tim
note: one paper, can't find it now, said the starch in sweet potatoes wasn't fully gelatinized until 180F, which is above the temp that the amylase in sweet potatoes is inactivated. Probably should have done several decoctions to increase the avail. starch for conversion
lead to more reading. Sweet potatoes have amylase (alpha and beta) in them, and a fair amount of starch. In africa, adding ground sweet potatoes to the sorgum mash significantly improved yields in beer making.
So this afternoons experiment:
2.5 pounds grated sweet potato (including skins)
2 gallons water at 150 F
Mashed for 90 minutes, did a single decoction (see note below)
Ended up with 1 1/2 gallons at sg 1.015
1 hour boil with 1/4 oz fuggles. to 3/4 gal and sg at end of boil 1.030
Will pitch s-05 (its what I have) when it cools. Not sure if this will even be drinkable, but the science is fun!
tim
note: one paper, can't find it now, said the starch in sweet potatoes wasn't fully gelatinized until 180F, which is above the temp that the amylase in sweet potatoes is inactivated. Probably should have done several decoctions to increase the avail. starch for conversion