To celebrate 4 July we examine yeasty matters in the Napa Valley.
In 2012 Michael Silacci (pictured), the amiable Opus One winemaker, was having lunch with Eric Asimov. They were mostly discussing viticulture but it became clear that Asimov assumed that Silacci relied on the local yeast population. Silacci had to correct him and explained that they used culured yeast (Lalvin EC-1118 Prise de Mousse) because native yeasts so often failed to complete fermentation, and he was also worried about increasing the risk of brettanomyces infection.
This conversation stuck in his mind, however, and he was therefore delighted when an in-house...