Hawai‘i Herald Columist
Imagine yourself a brewmaster at a sake brewery in central Japan. Tottori Prefecture, let’s say, or perhaps Gunma. You’re checking the condition of the fermentation in the tanks when you suddenly get the shock of your life. Instead of the rambunctious, frothy activity you expect as carbon oxide pushes up through the dissolving rice nutrients to produce a heady foam, there is . . . nothing. Bubbles of escaping gas rise to the surface, and there’s a quiescent layer of foam, but for all intents and purposes, it just looks dead to you. The sake has been contaminated by outside bacteria! The fermentation is not happening! This tank is going to have to be quarantined and destroyed before it affects the rest of the year’s production!
That’s pretty much how brewers viewed awanashi kobo, or non-foaming yeast, when it made an appearance, which, thanks to its extreme rarity, was hardly at all. At a time when there was no refrigeration, when there were no certified yeasts, when scientific brewing practices were not widely applied, there were many ways that sake could go bad. A simple lapse in hygiene — or a brewery worker bringing a natto musubi to work — could result in an infestation of lactic-acid producing hiochi bacteria that could put a brewery out of business.