There are a small number of companies brewing sake in the United States; and they generally do not produce premium sake. The most, however, do produce "Ginjou" level sake. According to the "Insider guide of sake", there used to be six (6) sake breweries in the U.S. (listed below the picture) but now there are only 4. It is not clear what types of rice they use except that it is "high-quality" rice from the Sacrament valley in California. Japanese short grain rice including Akita komachi and Koshi Hikari are grown there. These rices are good for eating but not for sake making. It appears that Calrose rice (85% of California short/medium grain rice being produced) is used for sake brewing in the U.S., for sure, by SakeOne. In terms of water, all the California manufacturers said they used water from Sierra Nevada mountains snow melt or in the case of the Oregon manufacturer, water from the aquifer at the edge of the Oregon forest (SakeOne).
1.Hakusan 白山 in Napa, California: This was the U.S. only brand and no Japanese sake with this name. It was owned and operated by a Japanese company that did not produce sake in Japan. We actually visited the brewery on a wine tasting trip to Napa soon after it opened and took a tour of the facility. We have fond memories of the experience. Unfortunately, it closed a few years ago. After moving to the east, we never saw this brand of sake for sale here. We still have a decorative mini-komokaburi container (empty) from our visit to Hakusan.
2. Hakushika 黒松白鹿 in Colorado: In 1992, they opened a sake brewery in Colorado but it was closed in 2000 and all sake production was moved back to Rokko brewery 六光蔵, Japan. We only bought and tasted regular "honjouzou" class sake over the years (I am not sure it was actually brewed in the U.S.--probably it was). We used it mostly as cooking sake.
3. Gekkeikan 月桂冠 in Folsom, California: Currently, our cooking sake is Gekkeikan. As a regular sake, it is not too bad and widely available. If you drink sake warm, this is certainly drinkable. Gekkeikan also makes semi-premium sake; "Haiku" 俳句, Silver, and "Black and Gold". Haiku is the "Tokubetsu Junmai" class and drinkable. It is brewed specifically to be consumed cold. "Black and Gold" is on order, when it arrives, we will have a tasting.
4. Takara 宝 in Berkley, California: The Japanese parent company is located in Kyoto 伏見, 京都. The majority of Shochikubai 松竹梅 sake sold here appears to be U.S. brewed. They also make "Junmai", "Tokubetsu junmai (to 60% polished)" and "Junmai Ginjo" (to 50% polished). Again, the "Junmai" variety is OK to drink warm and good for cooking. We have not tried others. They also produce sweet cooking wine "Takara mirin".
5. SakeOne in Forest grove, Oregon: This is a very interesting company and probably, at this point, the sole American brewery committed to making only premium sake. Although this is an American company and Momokawa 桃川 in Aomori 青森 has a partnership with it--providing the technical know-how (I suppose) and their brand name "Momokawa". The sake makers appear to be non-Japanese. Under the Momokawa name, they make four Ginjou sakes; Diamond, Silver, Ruby and Pearl. We tried these quite some years ago and did not like any of them. I decided to taste a few (Diamond and Silver) hoping the more recent brew may be different. The recent brews appear to be better than before but still not great. They also make fruit infused sake under the "Moonstone" label but I am a bit of a purist when it comes to sake and did not try them. Apparently they started making their top of the line "G joy" or "G sake". I found a place to buy this sake and will taste it when it arrives.
6. Ozeki 大関 Hollister in California: Ozeki is the oldest brewery of sake in the U.S. The parent company, Ozeki 大関, is located in Nada 灘. If I remember correctly, they started in an old dairy processing plant in US. Again, the regular sake they produce is just OK to drink warm or for cooking. Besides the regular brews, they produce Ginjo but I have not tried it. They also produce "special dry" and nigorizake.