Why can Arasama sake be kept for long without spoiling?

新政

Aramasa’s Itan Kyoso Kabushikigaisha is a special case in the world of sake, as most sake is meant to be consumed relatively young to enjoy its fresh, vibrant characteristics. The ability of Itan Kyoso to age for more than a year is a result of specific brewing techniques and its unique composition.
Here are the key factors that contribute to its aging potential:

• Acidity: A crucial element for the longevity of any beverage, including sake, is acidity. Aramasa Itan Kyoso is known for its exceptionally high acidity, often three times higher than typical sake. This is achieved through the generous use of white koji, a type of mold that produces a high amount of citric acid. The acidity acts as a natural preservative, protecting the sake from spoilage and providing a stable foundation for the flavors to evolve over time.
• Kimoto Method: Aramasa uses the traditional Kimoto method to brew this sake. This is an ancient and labor-intensive technique that allows for the natural development of lactic acid bacteria and a complex fermentation process. The resulting sake has a robust, full-bodied structure that is well-suited for long-term aging. The Kimoto method contributes to the sake’s overall durability and its ability to withstand the changes that occur during maturation.
• Wooden Barrel Fermentation: The sake is fermented in 130-year-old cedar barrels. This traditional practice can impart certain characteristics to the sake, but more importantly, it’s part of a brewing philosophy that values natural processes and a strong, resilient product. The wood itself may play a role in the aging process, but the primary benefit is the resulting sake’s complex and powerful profile.
• Unpasteurized (Nama) and Low-Temperature Storage: While some sake is pasteurized to stabilize it for a longer shelf life, Aramasa Itan Kyoso is often sold as an unpasteurized (“nama”) sake. However, it is specifically designed for aging under controlled conditions. This often involves a year or more of storage in a “ice-cold storage facility,” which is a form of low-temperature aging. This slow maturation process allows the flavors to mellow and integrate without the sake developing the off-flavors associated with poor storage.
  In essence, Aramasa intentionally brews Itan Kyoso to be “heretical” (as its name, Itan Kyoso, suggests). It challenges the conventional wisdom that sake is best enjoyed young by using a combination of high acidity, a traditional fermentation method, and careful aging to create a sake that is not just preserved, but actually improves over time. The high acid content and robust structure provide the necessary groundwork, while the precise storage conditions ensure that the aging process results in a more well-rounded and complex flavor profile.