Once in a while you will come across a bottle of sake with the words 山廃 (Yamahai) written on the label. What does 山廃 (Yamahai) mean and how does a 山廃 (Yamahai) sake taste like?
When the breweries first started making sake, they used a painstaking technique of mashing the steamed rice, koji and water together using a long oar-like bamboo poles tool called 'kai' to make the starter moto (酛). This process is called yama-oroshi (山卸し) and requires a lot of hard work as they have to do it every 3-4 hours at the temperature of 5 degrees celcius where lactic acid bacteria are active and germs are inertia. The sake made using this labourious process of yama-oroshi is called kimoto (生酛).
After centuries of using the kimoto method, in 1909, the National Research Institute of Brewing made a breakthrough in simplifying the brewing process when they discovered that all the hard work involved in tirelessly mixing the yeast starter from the yama-oroshi (山卸) was actually not necessary. Instead, by adding more water and keeping the moto at a higher temperature, the brewers could still produce a healthy environment for the yeast to proliferate. With the cessation of the yama-oroshi method, the new brewing method is simply called yamahai which means 'hai' (stop) of the yama-oroshi method.
With further advancement in technology, most breweries now add commercially available lactic acid and cultivated yeast in what has become known as the "quick fermentation" method - sokujo-moto (速醸系) which yields results in a little more than two weeks compared to four weeks from the previous methods.
In the current market, 90% of sakes are made using the sokujo method. Only a mere 9% are made using the yamahai method and 1% using the kimoto method. Due to the natural occurring lactic bacteria in the kimoto and yamahai methods, these sakes tend to have richer flavours, with the complex and distinct flavour of lactic acid aroma.
Check out the Yuki no Bosha Yamahai Junmai at our shop now!