What is flocculation? Flocculation, in the art of brewing sake, is the process of letting time drop the rice and yeast particles to the bottom of your container. Cooling your sake to below 40 degrees will decrease the time for this because the tiniest little particles of yeast and rice will combine and become heavy enough to fall to the bottom of the container. This goes by another name, "Cold Crashing". When cold crashing you are utilizing the cold temp to speed up the flocculation process to clear your brew.
Will flocculation make my sake clear as water? No, that is accomplished using highly milled rice and activated charcoal in a separate filtering process. What flocculation will do is help lighten up the Sake, this can take anywhere from one to two weeks.
Before filtering your sake by utilizing filtering production methods such as, activated charcoal, or clay, place it in the fridge. Yeast doesn't like to work well in cooler temperatures, and will stop producing alcohol.
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