The story of Yatsugatake and Southern Alps alcoholic beverages (P52-53)

The story of Yatsugatake and Southern Alps alcoholic beverages made with polished mountain water.

In the Yatsugatake and Southern Alps area, sake, whiskey, wine, beer, shochu and other kinds of alcoholic beverages (gen. sake) are made. The water used to produce delicious sake was first rained down on the peaks of the Yatsugatake and Southern Alps. After reaching the ground the rain water slowly filters down through the innards of the mountains, to eventually resurface again as delicious groundwater or spring water. All together this is a slow process.

The groundwater and spring water is essential for the production of sake.

It takes at least several decades, even tens of thousands of years before the rainwater seeps into the ground, through the mountain, to become groundwater, and to surface again. During this process, dust and pollutants are filtered out. The lack of oxygen deep underground eliminates pathogens like Escherichia coli. Ground and spring water show less fluctuation in water quality than surface water and other sources. This is an important property for brewing a stable quality sake.

Yatsugatake groundwater

Rock that is easily permeable for water

The Yatsugatake mountains were formed through repeated volcanic activities between twenty million and ten thousand years ago. The foot of the mountain is characterized by its abundance of spring water. There are several reasons for this. The main reason is that when the lava flow cools and solidifies underground, it becomes easily permeable for water, to move through and well up at places where the lava breaks through the surface.

  1. Lava is easy for water to permeate.
    When lava solidifies after an eruption it will become a rock mass with a lot of fissures and cracks. Lava that was blown up into the sky will form porous rock like pumice, volcanic gravel and scoria. Air bubbles that were trapped inside the lava are later released. Rain and melting water will seep into the rock and eventually resurface at the foot of the mountain.
  2. The volcano has a high altitude.
    A high altitude causes the forming of clouds and high precipitation. It also means that the average temperature is low, giving the slow melting snow time to seep into the ground.
  3. The complicated internal zoning of a volcano
    The process of build up and solidification of lava, gravel and ash is repeated many times over the centuries and millennia. As a result, the interior of the volcano becomes a complex geological structure. The flow of water is not uniform, turning places where the water comes together in large amounts into springs.

The groundwater of the Southern Alps

Spring water rich volcanoes

The “Fossa Magna” lowland rift divides the Northeast of Japan from the Southwest. The rift was created through activities of the Itoigawa-Shizuoka tectonic line, a major fault bordering the rift on the west side, alongside the Southern Alps. Among the mountains on this rift, only Mt. Kai komagatake in Hakushu town and Mukawa town in Hokuto city, Mt. Jizo, Mt. Kannon, and Mt. Ho-o are made of granite. Granite is formed when magma slowly cools under pressure deep underground. When coming up to the surface, the beautiful, mainly whitish rock will form a bedding for the mountain streams. Rock formed from the same magma can show various characteristics, like the andesite from the Yatsugatake mountains.

  1. Granite only rock material.
    Most granite in the area is of the “Phoenix type”. Granite of Mt. Kai Komagatake has a finer structure and has a grayish appearance. It is called “Kaikoma type”.
  2. Water accumulates in cracks
    The geological structure of the granite is further crushed through activities of the Toigawa-Shizuoka Tectonic Line, forming many small cracks in the rock formation. Rain and melting water on the mountains is collected when it seeps into the small cracks. The granite forms a natural filter constraining dust and dirt, and adds minerals, producing delicious ground water.

What has water quality to do with the taste of sake?

After the water has been filtered for many years through the strata of the mountains and enriched with ions dissolved into the water, it is stored in the bosom of the mountains. The taste of the water changes with the type and amount of ions dissolved in the water. This will also affect the taste of the liquor. The degree of influence varies depending on the type of liquor. It is said that with fewer ions the taste will be better and stronger. The people who produce sake have refined their skills, and carefully interact with the nature of the water they use.

Production Cooperation: Geotechnical Environmental Technology Co., Ltd.