Federweisser (also federweißer , from german feder, "feather", and weiß, "white"; from the appearance of the suspended yeast, also known as sturm, from german sturm, storm in austria), is an alcoholic beverage, typically 9% alcohol by volume, although versions of up to 13.5% alcohol by volume are not uncommon. (in contrast to all other alcoholic beverages, the alcohol content stated on a bottle of federweisser is inconclusive, and presents an uppermost limit, not the actual content at any given time.) it is the product of fermented freshly pressed grape juice, known as must. the term in principle includes all stages of fermentation from must to finished wine. across continental europe, it...

Source: Wikipedia