Sakekaeru (a pseudonym), a reporter writing for News47 (Japanese) visited the Niigata Sake Fair and stumbled across Fukugao's sake aged in whisky barrels. The tag on the neck of the bottle advises drinking it on the rocks or diluted with hot water. 

 

Fukugao describes the sake as having a mellow whisky aroma from the barrels, along with a strong flavour that blends beautifully with the umami of the sake. Sakekaeru describes it as having a particularly unique attack, with a sweep of whisky aroma, umami and acidity that caused him to exclaim out loud. He went on to describe it as like sake mixed with whisky. The sake is a 19% undiluted genshu but doesn't feel like it, maybe appearing lighter because it seems like you're drinking whisky. A complementary bitterness from the sake emerges in the mid-palate, whereas the acidity from the sake present from the beginning makes itself felt more strongly. The finish has bitterness, acidity, and whisky notes. His final evaluation is that it would never become a regular favourite, but is great when you want something different.

The label on the back of the bottle lists the ingredients as rice (product of Japan), rice koji (rice product of Japan) and brewing alcohol, without mentioning the rice variety, but the the Fukugao site says it's made with Gohyakumangoku milled to 60%. They also produce a sake aged in bourbon barrels.

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