You Can Thank A Mysterious Yeast Mutation For The Invention Of Cold Beer

The problem is that the origin of the hybrid yeast used in lager beer is relatively unknown. We know that a domesticated yeast (Saccharomyces cerevisiae) combined with a recently discovered yeast (Saccharomyces eubayanus) at some point to create an interspecies hybrid — but we’ve never understood how the two halves met.