Project Orval

My yeast bank is steadily growing. Untill recently I just saved commercial yeast and yeast from bottle-conditioned beer on slants or in the freezer. But last week I started a new project: "Project Orval". Orval beer is brewed using a Saccharomyces cerevisiae yeast strain in primary permentation. According to Stan Hieronymus in "Brew lika a monk" Orval uses a "yeast from the area" in secundary fermentation. This "yeast" is supposed to be a mixture of yeasts of both Saccharomyces and Brettanomyces. For a yeast enthusiast like me this is an experimental gold mine. I have streaked out the dregs of an orval bottle on a wort agar plate and picked a whole range of colonies looking different. I have seen big, small and tiny colonies. Of those I have now more then 15 clones which I plan to test (either all or some) in small scale (500 ml) fermentations using a neutral wort. This should be enough to fill one bottle from each fermentation. I will then test all bottles after a few months and see how my strains behave.