Beer brewers are increasingly hopping toward grapes as they seek to tap into the growing overseas interest in Japanese food ... and "Japan wine."

Brewing companies expect their wine products brewed from grapes grown in Japan to prove popular among overseas visitors to Japan and are looking to compensate for the shrinking consumption of beer by boosting wine sales.

However, production of pure Japanese wine is still limited. About 80 percent of wine produced in Japan in fiscal 2015 was brewed from imported grapes and imported concentrated juice, according to statistics by the National Tax Agency.

The major brewers are growing more grapes at their own expanding vineyards to ensure a stable production line of wine.

Suntory Wine International Ltd. is to market a wine product fashioned from grapes raised around Shiojiri in Nagano Prefecture under the brand name of the Suntory Shiojiri Winery in September. The new wine will be brewed in the city as well.

Suntory officials said the grapes' quality stability has been enhanced as growing techniques have improved. The company intends to make the new wine product a core brand in the future.

“Pure Japanese wine receives increased recognition as Japanese food gains global popularity,” said Yuji Yamazaki, president of Suntory Wine International.

According to Kirin Holdings Co., 380,000 kiloliters of wine is estimated to have been consumed in Japan in 2015, with pure Japanese wine accounting for just 5 percent of the total consumption.

However Mercian Corp., a Kirin subsidiary, expects “there will be much more business opportunities as the 2020 Tokyo Olympics approaches,” and plans to boost the sales of its Chateau Mercian wine in and beyond 2017.

While Asahi Group Holdings Ltd. is expected to release wine made from grapes raised in Yamagata and Yamanashi prefectures in April under the Sainte Neige brand, Sapporo Breweries Ltd. said it will make efforts to improve the sales of its existing Grande Polaire brand.

Japanese breweries are also providing support for grape farmers and expanding their own farms.

Suntory plans to expand its hectarage to raise production fivefold in five years of the Koshu grape in Yamanashi Prefecture.

The brewing firm is also urging contracted farmers to grow grapes at abandoned farmland in Nagano and Yamagata prefectures.

In the meantime, Kirin will expand its company-managed fields in Nagano and Yamanashi prefectures and elsewhere.