"Ask Beau" February 2006
"Why do they brew sake in the winter?"
The short answer is because they had nothing else to do! The long answer is that historically those who brewed sake in the winter were farmers in the summer. When the crop is harvested and the snow begins to fall, what else is there to do? These farmers would come from around the country to the breweries to help transform rice into sake, and they did so for generations! As such the work force to make sake presented itself in the winter, but that is not the only reason for making nihonshu (sake) in the coldest months.
Look up there! Now over there. Look under the table. Look on top of the door! Naturally occurring yeasts are everywhere. When one makes sake a considerable effort goes into getting the conditions right. To some this is 90% of the game! Yeast is a good thing if it is controlled, but natural airborne yeasts can play havoc on a vat of steaming sugars! Thus the freezing conditions of winter provided the perfect environment to cut down on those pesky airborne yeasts, which do not like cold weather.
Lastly, when one ferments one creates a great deal of heat! The production of sake is a wild and dangerous dance of getting temperatures correct. It is a never ending cycle! When things get too hot yeasts die, or conversely when things get to cold molds won't grow. And both yeast and mold are needed to make sake. The winter air makes a perfect natural air-conditioning system when dealing with the heat of fermentation. Crack a window and save a batch of sake!
People often refer to winter as death. The season of death. But for me winter is really the season of life as new sake is being born.
Please send your sake specific questions to askbeau2 @ truesake.com. (This address is not for general questions and I only review the questions once per month. All correspondence should use info @ truesake.com.)