I've been working on a pomagranate mead that has been fermenting for 3 weeks. I just racked it for the first time today and I tried a some, it was super sour... anyone know if this is normal and if it will go away and have the original pomagranate taste back. Also what might of caused this, did my pomagranate mead go bad or something
I can think of two reasons why your mead is sour:
Pomegranate juice is sour, with a pH of around 3.0. Assuming you've made 1 gallon batch, 16oz of pomegranate juice is enough to be noticeably tart. 16 oz of a pH 3.0 liquid diluted to 1 gallon yields a pH of around 3.9 which, without any sugar to balance the acid, would taste quite sour.
Your mead was infected by acetobacter while fermenting. There's a group of bacteria called acetobacter that produce acid. They are responsible for sour pickles, sauerkraut, and vinegar. If this is the case, your mead would have a vinegar smell and taste.
My bet is that you don't have an infection; it's just the natural sourness of the pomegranate juice.