>>150151
the stuff you buy at a store just tastes like soda
if you want the real kvass experience then buy some rye bread, cut it up and toast it until its black, put it in a jar with some water, and add a source of sugar like fruit juice or molasses (white sugar will taste like ass), and ferment it with some yeast
it will taste completely different from the store stuff
my reccomendation overall: just get a good beer instead, like a belgian ale or something