Ochiawa (falling foam stage of fermentation)

Ochiawa (literally "falling foam") is a phenomenon seen in the later stage of sake fermentation, after fermentation has reached its peak. At this point, the foam known as takaawa (高泡, "high foam") gradually subsides, and when the mash is stirred, the foam sinks and disappears with a audible sound. This way the foam vanishes gave the stage its name, ochiawa. Ochiawa is also an important indicator during fermentation. Its appearance suggests that fermentation is nearing completion. At this stage, the flavor and aroma of the sake become more pronounced, and a good finished product is anticipated.