As grapes were never indigenous to Japan all grapevines had been introduced to the region with the movement of the spice route and silk roads over 2,000 years. It is believed that about 1,300 years ago grapevines were introduced to Japan where the climate was too hot, cold, wet – too extreme – to grow grapes for wine.
Ultimately the existing grape variety most successfully grown in Japan became known as Koshu, which was the then name for the prefecture in which it grew. This prefecture then took the name of a Japanese prince and became Yamanashi, which remains the principal region producing Koshu. Responsible today for 40% of all Japanese grown wine grapes, it is believed to be the naturalised hybrid of a Georgian grape variety. Ampelographers continue to isolate the DNA of Koshu, but we do not actually know, outright, its source. What we do know is that it is a lurid pink on the vine, generally grown in the local tana method (overhead bamboo trellis).
Château Mercian is the oldest established winery in Japan, starting out in 1870 having sent two young men to France to understand wine making in the European tradition. Indeed the descendants of these two men are still growing Koshu for Mercian today.
Koshu grapes are grown in the Iwasake District of the Yamanashi Prefecture where the soils gravel and clay with good drainage. Harvest took place from late September to early October. Fermentation in oak barrel at between 18-21℃ for approximately 14 days, the wine was aged for 4 months in oak barrel.
Citrus aromas of kabosu and yuzu with notes of white flowers, vanilla, almonds and nuts. With refreshing balanced acidity, rich fruit flavours and minerality spread in the mouth.
Koshu, like many things Japanese, is all about subtlety of flavour, texture and the wine being part of a greater organoleptic experience than the wine itself, so imagine drinking this with a slurpy bowl of hot yum from a chilly noodle shop in the hills. It's part of the whole, not the whole, therefore the fruit is not overt, it's more about texture, acidity and finish rather than outright fruit flavour. Or why not go for white fish tempura or grilled chicken with yuzu pepper!