Food for thought: Koshu and sushi pairing

Japan’s skilled winemakers are turning the Koshu grape into beautiful liquid that pairs perfectly with the country’s wide array of dishes. At a recent db event, we highlighted just how well Koshu goes with food. By Patrick Schmitt MW

It was satisfying to see a packed room of high profile drinks industry figures in London last month for a masterclass on Japanese wine and food. Taking place at Asia House on 30 September, during Japan Week – a celebration of London’s Japanese food and drink scene – and just ahead of the Tokyo kick-off for the Rugby World Cup, it was an ideal moment to focus on all things Japanese. It was also brilliant to observe that the wine trade agreed.

But it wasn’t just the current focus on Japan – be it sport, cooking and culture – that made this event appealing for wine buyers, writers, and educators. It was the fact that Japanese wine offers the consumer something new, as well as being complementary to Japanese food, which is, of course, prevalent worldwide, in Japanese restaurants from fine dining to fast food, or in others, through fusing Japanese flavours into dishes.

Not only do the trade and consumers want to discover fresh wine experiences, they also want to taste food and wine matches that are authentic, distinctive, delicious and tied to particular places. But such combinations of drinks and dishes must pair well together – even if, on their own, they are first-rate.

With this in mind, this London event set out to test the food pairing potential of Japenese wines, in particular, its flagship grape, Koshu. Before the dishes were served, the attendees were given a brief introduction to the Japanese wine scene to better understand the style of wines this country produces.

To help position the climatic character of Japan’s key grape-growing region for Koshu, which is called Yamanashi, some comparisons were drawn with other areas. One of these was well known to all the attendees – the UK, specifically the south west of the country, because this area, like Yamanashi in Japan, faces the challenge of extensive rainfall during the growing season, especially during harvest time, and hence, both places tend to produce delicate styles of wine. Indeed, a picture of the verdant landscape of Hampshire, with the South Downs in the background, was not unlike another showing Yamanashi from the highest vineyards of Tomi no Oka, a winery owned by Suntory. However, there was one big difference – the lush vegetation of the Japanese valley is backed by the striking cone-shaped volcano that is Mount Fuji.

Importantly, this natural wonder and the mountain range it is part of protects the basin-shaped Yamanashi from the Pacific Ocean’s prevailing winds, rainfall, and typhoons. Nevertheless, this is a wet, humid region. While Yamanashi’s vineyards lie on the 35th Parallel North, which runs through California, southern Spain and Italy, this part of Japan differs from these wine regions because of the incidence of summer rainfall, with around 80% of the 800mm-1,000mm of precipitation of Yamanashi falling during the growing season. Furthermore, Yamanashi’s viticutlural heartland, Katsunuma, is one of the warmest places in Japan. Combine the heat, and summertime rainfall, and Yamanashi is climatically more like Australia’s New South Wales, particularly the Hunter Valley, than it is somewhere like Sonoma, or, indeed, Hampshire.

Koshu, however, thrives in Yamanashi, not only thanks to its rot-resistant skins, but also because of its natural adaption to the fertile clay soils of the area, which overlay a free-draining volcanic base, preventing waterlogging.

Protecting the grapes

In keeping with Japan’s reputation for precision in technology, the country’s viticulturists go to extraordinary lengths to protect the Koshu grapes, choosing to train them high in pergolas, improving airflow around the bunches, while also shading the grapes from temperature extremes. They also protect them from summer rainfall with little wax paper hats stapled together above each bunch, ensuring that the water doesn’t get inside the bunches, otherwise the water might start the spread of rot.

Koshu is believed to have arrived in Japan via the Silk Road from the Caucasus around 1,000 years ago, but it wasn’t until the 1870s that the grape was used to make wine, having previously been grown for eating.

But the use of Koshu is linked to the birth of the Japanese wine industry, because the country’s first bottles of wine were made with the grape, and hailed from the city of Kofu – in the heart of the Yamanashi wine region.

It is a hybrid grape, believed to have originated naturally by a crossing of the European Vitis vinifera and an Asian Vitis species – although Koshu contains over 70% of the former. In 2009, Koshu of Japan was founded to champion the grape, and in 2013 it was recognised by the OIV, adding greater impetus to Japanese wine producers to promote the variety more widely.

Notably, there is something so distinctly Japanese about the way Koshu looks. With beautiful deep-pink berries, it complements the slightly paler shades of the cherry blossoms that the country is so famous for. In essence, Koshu’s colouring is similar to Pinot Gris or Gewürztraminer, albeit with a slightly deeper pink.

So what does it taste like? Koshu-based wines are delicate. Naturally around 11% ABV – and rarely above 12% ABV – they are never tiring to drink, or forceful in character, but deliver something subtly intriguing. In essence, the wines made from Koshu tend to have a combination of flavours, from citrus (particularly yuzu, or sudachi – Japanese ‘orange’ or ‘lime’) to yellow fruit. To draw comparisons with well-known European whites, Koshu has some of the flavours of Muscadet, with its freshness and breadiness – the Japanese tend to give Koshu relatively extended lees contact – but also Albariño, with its lime-acid and peach fruit. Koshu also has something more unique, in the form of a gentle salty note, as though someone has added a drop of soy to the glass. Other regular descriptors for Koshu-based whites, include creamed rice and mint. Over the years, Koshu has been compared most commonly with Muscadet’s Melon de Bourgogne, along with Sémillon – particularly when sourced from Australia’s Hunter Valley – along with aforementioned Albariño, when hailing from Galicia in northern Spain. Notably, all these grapes tend to come from damp, coastal regions. But Koshu can also resemble light, dry styles of Chenin Blanc from the Loire and South Africa, as well as Pinot Blanc from Alsace.

More obscure comparisons from sommeliers and wine writers have included Chasselas from Switzerland’s cool Alpine sloes, Arinto from the exposed vineyards of the Azores, and Feteasca Alba from Romania.

Koshu does, however, produce wine in a range of styles, ensuring it matches different tastes, and rewards exploration. Some of this diversity relates to particular sites, where certain aspects and soils – particularly if they are free-draining – produce wines of great intensity and individuality. One of these is the Misawa vineyard in Akeno, where celebrated Koshu producer Grace makes the most of high altitude – coupled with, unusually, vertical-shoot position training – to produce a remarkably intense, peachy Koshu. Another, the Isehara vineyard from highly rated Koshu producer Katsunuma, yields a sought-after example bursting with pink grapefruit, not unlike a top-end Sauvignon Blanc from the Loire.

However, many of the most obvious variations in Koshu’s wine style come from practices in the cellar. As mentioned above, lees contact can be used to build in a bready complexity, as well as more texture to the naturally light-bodied wine, and with great success – much like the techniques used in Muscadet with the delicate Melon de Bourgogne grape.

Barrel fermentations and ageing, including new oak, albeit in low proportions, can yield surprisingly successful results with this subtle variety. The peanut character derived from high-quality barriques seems to marry well with the lemon and peach flavours of Koshu, in the same way sweet oak complements ripe Sauvignon Blanc in Bordeaux.

But it’s not just isolating particular plots or playing with lees and oak contact in the cellar that yields various expressions of Koshu. Some of the most notable wines come from extended skin contact – Koshu produces particularly good ‘orange’ wines, coming in a range of hues, from light amber to egg yolk coloured cloudy wines. Gently grippy, often with aromas of smoked tea leaves, these are complex, versatile expressions that are gaining popularity in Japan, where there is a strong demand for ‘low-intervention’ wines (more so than organic or biodynamic certified products).

A further interesting and refreshing use for Koshu is in the creation of sparkling wines. Lumière crafts a delicious traditional method fizz with the grape, with the persistent mousse augmenting the citrus freshness of Koshu on the palate.

In short, there’s almost nothing that Koshu makers haven’t tried, with the new wave of winemakers now looking to make Koshu with no added sulphur, as well as trialling new fermentation vessels, from concrete eggs to amphorae – yes, the experiments common in the cellars of Western Europe are also to be found in this outpost for winemaking.

It’s not just curiosity that is motivating Japanese Koshu producers, whose spiritual home is Yamanashi, to try new things with this grape. They are driven by a desire to create wines that will pair successfully with the full range of flavours in Japanese cuisine, from the extremely delicate to the strong and challenging. One aspect that’s clear, however, is the brilliant combination of the salty-citric nature of Koshu and Japan’s raw fish-based food.

For example, the likes of sparkling Koshu is an ideal accompaniment to the more subtle styles of raw fish-based Japanese food, where traditionally promoted wine matches such as oily Pinot Gris or aromatic Gewürztraminer would overpower the cuisine. However, where more pungent dashi-flavoured fare is on offer, requiring something weightier, one can opt for a Koshu expression with extended lees contact or some additional skin maceration.

Successful discovery

One remarkable pairing is the intensely salty, creamy sea urchin – called ‘uni’ – with a Koshu orange wine. Another extraordinarily successful discovery is roast Wagyu beef and wasabi paired with the aforementioned oak-influenced Koshu – proving the versatility of this grape, grown in Japan for around nine centuries before its winemaking capabilities were realised. In particular, Koshu is brilliant at handling the fiery sensation of wasabi. As for one further food pairing discovery, that came in the form of Koshu and the finest Caspian Caviar, which was also highlighted at this event. Bearing in mind the Koshu grape is believed to have travelled to Japan from the Caucasus, which borders the Caspian Sea, there may be a historical connection between this distinctly Japanese grape and Russia’s most famous luxury food.

On the other hand, wines made from Koshu do tend to struggle to pair successfully with dishes incorporating butter and cream, two ingredients that may be common in the cuisine of France, but not used in Japanese cooking.

As sommeliers in the UK start to discover Koshu’s food pairing potential, the grape is just starting to appear in restaurants in the UK. A pioneer for Koshu in the UK was the late Gerard Basset MS, MW, who once poured Koshu from Grace at his TerraVina hotel in the New Forest by the glass. Today, thanks to research commissioned by db and provided by Wine Picker, one can find Koshu at a range of places in the UK, from Hide to La Trompette (see boxout).

Why should you want to stock Koshu? Well, as shown by the masterclass, Koshu offers an intriguing combination: pale pink berries in the shadow of Mount Fuji grown with painstaking attention to detail, producing something that’s delicate, fresh and with a touch of umami.

It has a subtle appeal, complexity, and an ability to pair successfully with one of the world’s most popular and revered cuisines – Japan’s raw fish-based food.

It’s also the emblematic of Japan’s fast-emerging wine industry.

And, it is right on trend with demand in mature wine-drinking markets, where the call is for something light in body, low in alcohol, refreshing, and authentic.

So, while Japan works with a number of grape varieties, from widely planted hybrid red grape Muscat Bailey A to international varieties such as Merlot, Pinot Noir and Cabernet, and in whites, increasing amounts of very good Chardonnay, it is the Koshu grape that’s become the primary focus for Japanese vignerons looking to stand out in the market at home and abroad.

The food and wines served at the masterclass

1. Lumière, Sparkling Koshu, 2017 Region: Fuefuki, Yamanashi ABV: 11%

2. Château Mercian, Yamanashi Koshu, 2018 Region: Yamanashi ABV: 12% – Served with sea bass sashimi with light soy sauce

3. Grace, Koshu Private Reserve, 2018 Region: Yamanashi, Katsunuma village ABV: 11.9%

4. SoRyu, Curious Type N, 2018 Region: Yamanashi, Katsunuma village ABV: 12.4% – Served with spinach, courgette and pickled ginger California roll

5. Kurambon, Sol Lucet Koshu, 2018 Region: Yamanashi ABV: 12% – Served with nori roll with avocado and cucumber, pickled ginger and wasabi

6. Haramo, Koshu, 2017 Region: Yamanashi, Katsunuma village ABV: 11.5% – Served with scallop sashimi encrusted with pepper and coriander

7. Katsunuma Jozo, Aruga Branca Issehara, 2017 Region: Yamanashi ABV: 11% – Served with California roll with crab and mango with wasabi

8. Kurambon, Natural Koshu, 2018 Region: Yamanashi ABV: 12% – Served with salmon nigiri with pickled ginger

9. Katsunuma Jozo, Aruga Branca Pipa, 2016 Region: Yamanashi ABV: 11.5% – Served with seared beef nigiri with wasabi

10. Château Mercian, Fuefuki Koshu Gris de Gris, 2018 Region: Fuefuki District, Fuefuki shi Yamanashi ABV: 11.5%

11. Lumière, Prestige Class Orange, 2018 Region: Fuefuki, Yamanashi ABV: 11% – Served with royal Oscietra caviar from WG White