i'm getting started on a kolsch this afternoon and i'd like to reduce the color as much as possible. to this end i want to reduce the boil to 45 min. i need some help in figuring my efficiency to make up for less boil off. my usual numbers are as follows:
90 min boil, 8.75g in to boiler, boiled down to 6g, efficiency is consistently 80-85%. i've already figured to reduce my volume into boiler to 7.75g. can anyone help me figure a new efficiency % to make up for less volume!?