How do you measure the percentage of alcohol in homemade cider?
It is difficult to determine the alcohol in the finished product without first knowing the Specific Gravity (S.G.) of the liquid BEFORE it fermented. Next time, measure and record the S.G. of the must or wort before fermentation. (You use a hydrometer to measure S.G.) After fermentation is complete, measure the S.G. again. Subtract the second reading from the first, and multiply the difference by 125. The will be the ABV (alcohol by volume) of the finished product in percent.