The KELLERBIER is unfiltered and naturally cloudy thanks to the original Karmeliten brewer's yeast, which contains large amounts of vitamins B6 and B12. Natural yeast is very sensitive to heat. Since the brewery does not use any preservation, such as pasteurization, in order to maintain the freshness of the ingredients, they rely on the highest quality in taste and limit the availability of Karmeliten KELLERBIER to the cooler season.