Why bitter? Bitter in beer comes from hops, which they weren't using then.
Everyone accepting Ema running around in bare legs, huh. Guess the witch can do what she wants.
No, they used hops in Germany then. The first mention of hops being used in brewing there is in 1079, and they were cultivated since the 700s. The Reinheitsgebot was applied in 1516 in Bavaria and required that beer only be made from water, barley, and hops, and that was adopted from an even earlier law from 1487. Hops must have been well-established in beer production by then to be mentioned as a key ingredient.