You may have come across the word “Yamahai” when you were trying to choose a sake bottle to purchase. It’s short for “Yamahai shikomi” or “Yamahai zukuri” which is preparing the yeast starter for sake brewing, no longer so common today. We’ll give you more information on it, so keep reading.
Kimoto – Yamahai shikomi Roots
Kimoto, sake mash, is a traditional and particular way of getting the yeast started. When sake is usually made, the starch in the rice is converted to sugar, allowing the yeast to multiply. The yeast is naturally very acidic and eliminates other bacteria, perfect because the sake yeast needs a lactic environment to grow. Kimoto is a traditional method relying on the ingredients to naturally kill off the bacteria with lactic acid. It is a slow process and the yeast takes a lot longer to multiply than your typical sake.
There is also a labor-intensive method called yamaoroshi. For yamaoroshi, rice, water, and koji are ground and mixed by groups of 2 to 3 people using a kaibo or paddle type tool. From the early cold winter mornings to midnight, the mash must be stirred every 2-3 hours. It may even take an entire day.
As you can imagine, yamaoroshi is a lot of work. That’s how yamahai came about. The “hai” in yamahai actually means “cease,” which eliminated the intense labor needed for yamaoroshi. Yamahai relies on the enzymes in the koji to convert the rice, ending with the same results as yamaoroshi. In 1909, it was finally proven that there was no difference in the starter yeast for yamahai and yamaoroshi.
Yamahai zukuri Basics
Yamahai zukuri is still a process where people must work by hand to ensure that the lactic acid made by the lactic acid bacteria thrives. The process takes about an entire month. Later, lactic acid was added to the yeast starter to speed up the process. Coined the “sokujo kei” method, it took only 2 weeks, about half of the time of yamahai zukuri. Most breweries today use this shortcut. It is said that the methods used to make sake are 90% sokujo, 9% yamahai, and 1% kimoto, so yamahai is really becoming rare.
One of the main reasons why some breweries choose to continue using the yamahai method is because it results in a distinct taste. The yamahai method gives sake a good balance of tanginess and bitterness so we recommend having it warm and mellow.
Try to keep the information in this article in mind the next time you see “yamahai” on a sake bottle.