Home Distiller

I did my first run today. Started with about 20 gallons of mash and recovered a little over a gallon and a half plus about a pint of heads and another of tails. Straight corn mash. The alcohol content of the mash was 10% going by the sg readings. It smells and tastes good. The refractometer I bought says the final alcohol content is 40%. That sure doesn’t seem right to me. I guess I’ll invest in a tva hydrometer.