【Reading】きもとづくり

【English Name】Kimoto Method

Kimoto-zukuri is known as one of the oldest techniques in sake brewing. Its greatest characteristic is that, in the process of preparing the yeast starter (shubo, or moto), rather than adding lactic acid from outside, naturally occurring lactic acid bacteria derived from the brewery and the natural environment are utilized to eliminate unwanted microorganisms.

Inside the shubo tank, first nitrate-reducing bacteria and wild yeasts proliferate vigorously, but from around the fifth day lactic acid bacteria gradually become dominant. Around the 12th day, spherical lactic acid bacteria, and around the 15th day, rod-shaped lactic acid bacteria each reach their most active period. Yet these too gradually decline due to the acid they themselves produce, and ultimately an acidic environment in which unwanted microorganisms cannot live is established. At this stage, sake yeast is introduced and cultured carefully, step by step.

The yeast thus tempered is said to be full of vitality and to draw out a rich flavor even in low-temperature fermentation. The finished sake is fine-textured and mellow, and is also suited to long-term aging. However, there is also a risk that an unpleasant sourness will arise if the process is mishandled.

For the purpose of omitting the extremely labor-intensive "yama-oroshi" (mash-pole grinding) work, the yamahai-moto was developed at the National Brewing Experiment Station in 1909 (Meiji 42). There was once a time when very few breweries inherited the kimoto method, but now, amid a current of reevaluating traditional techniques, it is once again in the spotlight. At the sushi table, the enjoyment of pairing kimoto-brewed sake with sushi is also spreading.