Sadoya wine dinner at Saki Farringdon

Japanese wine is having something of a moment. Last week a series of events were held in London to showcase Japan's winemaking prowess to the city's wine elite, including a lunch attended by a who's who of the wine world: Michael Broadbent, Jancis Robinson and Hugh Johnson to name but three.

The focus was on Japan's flagship white grape, Koshu. Helping to build a buzz around Japan's great white hope, Jancis Robinson MW was enlisted to host a Koshu seminar at the Koshu of Japan trade tasting, in which she described the grape, which is being marketed as an alternative to saké for matching with Japanese food, as 'quietly gallant'. Made in the Yamanashi Prefecture, the Japanese government has put its support behind a campaign to promote Koshu in the UK and other European export markets, targeting Japanese restaurants.

My encounter with Koshu came at Saki restaurant in Farringdon, at a dinner hosted by Hirohisa Imai, owner of Sadoya, one of Japan's leading producers. Light bodied and almost transparent, the tank sample of 2010 Sadoya Zenkouji Kitahara Koshu had delicate, yuzu citrus flavours, along with hints of lychee and lime blossom. Jancis accurately describes its purity as 'zen-like'.

Sat beside Imai at the dinner was long-term friend and former owner of Château Cos d'Estournel Bruno Prats. I wondered whether Prats harboured dreams of a Japanese wine project, to add to his Portuguese, Chilean, South African and Spanish ventures, but he assured me he has no plans to invest in Japan, and that his final wine project, an old vine Monastrell from Alicante called 'Alfinal', or 'the end' in Spanish, will launch at Vinexpo in Bordeaux this June.

Leaving Prats and Imai to get back to their Koshu, I took my place at a black cubed table with a white, gravel-filled centre sprouting four phallic candles, like erotic stalagmites – the most curious centrepiece I've ever encountered in a restaurant. Not only the only blonde, but the only Brit, I felt like I'd stepped inside a scene from Sophia Coppola's Lost in Translation.

The seven course dinner paired a different Sadoya wine with each dish. Founded in 1917, Sadoya was appointed purveyor to the Japanese Imperial Household in 1940 – a title it retains to this day. The feast commenced with a trio of nibbles inspired by Japanese New Year celebrations: tiny fish representing fertility, a golden egg yolk set atop an egg white in a coconut ice-like cube for prosperity, and a white radish and red(ish) carrot – Japan's lucky colours.

The accompanying Sadoya Cabernet Sauvignon sparkling rosé was an attractive onion skin pink, and had persistent petillance and a feminine nose of summer fruits. A simple sashimi selection followed, which matched incredibly well with the crisp, citrusy Koshu. We then moved on to scallop, king prawn and Lotus root kakiage (tempura) that looked like a tumor but tasted divine. Crunchy and moorish, it's the Japanese equivalent of beer battered cod. The matching 2004 dry Semillon was decidedly dull, and almost ghostly in its lack of character.

Sat to my left was a Japanese lady who had emigrated to England 30 years prior and now worked at the Japanese Embassy in London. After kindly inviting me to a forthcoming saké tasting, she told me of her predilection for English comedy and costume drama, name checking Only Fools and Horses and Downton Abbey as her particular favourites. Curiouser and curiouser. A fascinating dish followed: braised pork belly in a potato sauce, served in a yellow flower-shaped bowl and garnished with two bright green beans. Soft, comforting and tremendously tender, it was the best pork I've ever tasted.

We were then presented with a duo of exciting wines: Sadoya Château Brillant Cabernet Sauvignon 1992 and Château Brillant Cabernet/Merlot 1962. The '92 was remarkably youthful for its 19 years, and still incredibly fruit forward, with a nose of black cherries, and red currants. The palate was smooth and rounded, showing traces of aged Bordeaux. The '62 also seemed young for its years, and reassuringly full of life. Savoury and serious, it had aromas of pencil shavings, cedar wood, cigar box and tobacco smoke, with a spicy, sour cherry finish.

The '62 was matched with black cod with truffle miso - a sublime dish that had me reaching for superlatives, so rapturous was its divine, hedonistic flavour. Intense, intoxicating, indulgent, I almost genuflected in front of the plate in reverence to it. The final wine of the night was a curio: Sadoya Zenkouji Kitahara Sweet Semillon 2008, paired with green tea tiramisu, that sang of apricot and orange peel. In the UK's highly competitive wine retail arena, the 'quietly gallant' Koshu is not going to be an easy sell, but it's exciting to see the white grape has entered the world wine arena. And with Sadoya producing some stunning reds, Japan's wine future looks to be in the pink.