2020 Grace Koshu Toriibira Vineyard Private Reserve

Recently, we went to a gathering at our friend's home and one of the couples brought this 2020 Grace Koshu Torribira Vineyard Private Reserve wine. Although this is a wine made in Japan, our friends bought this wine in China when they were there on a recent visit.
It was a real treat and an eye-opener since we had never had a wine from Japan before and the gathering was abuzz with wanting to know what the Koshu grape could be. We learned on the Internet that the Koshu grape is probably a Vitis vinifera. It is grown in Yamanashi Prefecture in the Koshu Valley, where the grape has been grown and made into wine since the Meiji Era (1868-1912).¹
Having just the barest of information, we tasted the wine. It was very floral on the nose, reminding some of Gewürztraminer. The wine was light and clean and went well with the platter of cheese and crackers.
Wanting to learn more about the Koshu Grape, I went on the Internet and dug a little deeper. Grace is the name of the winery. Toriibira is the name of the district on the south-western slopes of Mount Kashio. This location is blessed with plenty of sunshine and cool breezes blowing down from the Sasago Pass. There exists area a profound temperature difference between day and night, providing the perfect conditions for the grapes to ripen well. The gravelly, well-drained, clayey soils result in grapes with robust flavour that is reflected in the depth of the wines.
The Koshu grape originated in the distant South Caucasus, but how the Koshu arrived in Japan remains a mystery to this day. After more than a thousand years, rather than falling out of favour it is greatly treasured. In 2010, it became the first grape variety indigenous to Japan to be included as a registered grape variety of the International Organisation of Vines and Wines (O.I.V.), allowing it to appear as a varietal name on labels.
Grace grows their Koshu grapes using vertical shoot positioning.

The resulting Koshu grape berries are smaller, have higher sugar content and containing more malic acid than the traditional Koshu grown on pergolas. This allows malo-lactic fermentation to occur naturally, something which seldom happens to conventionally-grown Koshu, and which gives the resulting wine a unique character. I concur.

References:
1. Grave Wines.