Koshu Wine and Japanese Winemaking Tradition
Yamanashi Prefecture, Japan — Katsunuma wine district
Koshu is a pink-skinned grape variety cultivated in Japan's Yamanashi Prefecture for over a thousand years, producing a distinctive white wine style celebrated for its pale colour, delicate floral-citrus aromatics, subtle bitterness, and natural affinity with Japanese cuisine. Japanese winemaking traces its origins to the Meiji period when Yamanashi entrepreneurs Masanari Tsuchiya and Ryuken Takano travelled to France to study viticulture, establishing Méthode Champenoise and French technique understanding. Koshu wine is uniquely positioned among world white wines—low in alcohol (typically 11–12%), high in umami-synergistic mineral qualities, and carrying a slight phenolic bitterness from grape skin contact that complements sushi, sashimi, and kaiseki courses with unmatched harmony. The Katsunuma wine district south of Kofu city became Japan's premier wine region, home to Château Mercian, Grace Wine, Suntory Tomi No Oka, and smaller artisanal producers. Koshu received official OIV recognition as a variety in 2010, opening European restaurant wine lists. Producers pursue skin-contact orange wine expressions, sur lie ageing, and pétillant naturel styles alongside classical still wines.