Koshu Comes of Age

Koshu is a pink-skinned grape that has grown in Yamanashi, west of Tokyo, for centuries. For most of that time it was a table grape or the base of sweet, forgettable wine. Over the past twenty years Yamanashi winemakers have turned it into a delicate, dry white that sommeliers in London, Paris and Hong Kong now pair with sushi and seafood, and it has become the main name in Japanese wine abroad.

A grape with an unusual history

Local legend says Koshu was first planted in the Kofu basin about a thousand years ago, carried along the Silk Road from the Caucasus via China. Genetic research by Japan’s National Research Institute of Brewing in the 2010s supported part of that story: Koshu is mostly Vitis vinifera, the European wine grape, with a share of DNA from a wild East Asian vine species.

The grape has thick, lilac-pink skins that resist Japan’s humid summers, which is why it survived where many European varieties struggled. Its flavours are gentle: citrus and yuzu, white peach, a light mineral edge and sometimes a slight bitterness from the skins. Alcohol is usually around 11 to 12 percent.

From sweet table wine to dry, food-friendly white

Until the 1990s most Koshu wine was sweetened and sold locally. A generation of producers changed that by picking riper fruit, fermenting dry and borrowing techniques from Europe:

• Sur lie ageing, resting the wine on its yeast after fermentation, adds texture to a naturally light grape. Château Mercian and others helped popularise it.
• Vineyard work, including moving from tall overhead pergolas to lower vertical trellises in some plots, concentrates flavour.
• Skin-contact and orange styles use the pink skins to add colour, aroma and grip.
• Traditional-method sparkling Koshu has become a popular aperitif in Japanese restaurants.

Building a brand abroad

The labelling rules mattered. Before 2018, wine bottled in Japan from imported concentrate could look domestic on the shelf. The new rules give buyers abroad a clear guarantee of origin.

The producers to know

Yamanashi has the largest number of wineries of any prefecture in Japan, many of them around Katsunuma and Koshu city. They range from corporate-owned estates to small family cellars:

• Grace Wine (Chuo Budoshu) — family winery in Katsunuma whose single-vineyard Koshu won international recognition.
• Château Mercian — owned by the Kirin group and one of the pioneers of dry, sur lie Koshu.
• Suntory Tomi no Oka Winery — a large estate west of Kofu making Koshu alongside red varieties.
• Smaller cellars such as Lumière, Haramo and Marufuji, which offer sparkling, orange and older-vintage styles.

The constraints

Koshu’s international profile is growing faster than its supply. Volumes are small compared with mainstream wine regions, and vineyard land in Yamanashi competes with peaches, grapes for eating and housing. Many grape growers are elderly, and some vineyards have been abandoned. Wineries increasingly plant and farm their own vineyards rather than buying grapes from contract farmers.

Price is the other issue. Small-scale farming on expensive land makes Koshu costlier than comparable whites from Europe or the New World. Producers sell it as a premium wine for Japanese cuisine rather than an everyday white.

What this means for overseas partners

• Importers and distributors can offer a white wine with a clear origin story and few direct competitors. Japanese restaurants abroad are the natural first channel.
• Sommeliers and restaurants will find Koshu’s low alcohol and restraint work with raw fish, tempura and lightly seasoned vegetable dishes, where many fuller whites overpower the food.
• Retailers can pair Koshu with sake and Japanese whisky in a Japan drinks range, as Japan Wine is still new to most shoppers.
• Investors and wine-tourism operators can look at Yamanashi’s wineries, within two hours of Tokyo by train, which combine tastings with Mount Fuji views and hot springs.

Frequently asked questions

What does Koshu wine taste like?
Usually light and dry, with citrus, yuzu and white peach notes, gentle acidity and a clean, slightly mineral finish.

Where is Koshu grown?
Mainly in Yamanashi Prefecture, especially around Katsunuma and Koshu city in the Kofu basin, about 100 km west of Tokyo.

What food goes with Koshu?
Sushi, sashimi, tempura, grilled fish and other light Japanese dishes. It also suits oysters and simply prepared vegetables.

Outlook

Koshu is unlikely to become a high-volume export, and that is part of its appeal. As interest in Japanese food keeps growing, a dry white made from a grape found almost nowhere else gives sommeliers something new to pour. The main question is whether Yamanashi can keep enough vineyards farmed to meet that demand.