This year is hard (mostly)

The National Research Institute of Brewing (NRIB) produces an annual report predicting the hardness of rice, and therefore how readily it will dissolve during sake brewing, based on weather patterns while the rice plans were growing. 

While brewers originally had to figure out for themselves what this year’s rice was going to behave like during brewing, research by the NRIB found that the properties of the starch in the rice (and therefore its solubility) could be predicted very accurately from the weather while the grains were ripening.

Their summary of the weather points out that northern and eastern areas of Japan had above-average temperatures from mid-July to mid-August, normal temperatures from mid to end August, then higher temperatures in September. Western Japan had normal temperatures mid to end July, but then higher than normal temperatures from early August to late September.

They predict that the impact of these weather patterns will be:

• Early-maturing varieties (such as Gohyakumangoku) that ripen from mid to late July should be around the same or slightly less soluble than normal
• Varieties that ripen around early to mid August will be as soluble as usual in Hokkaido and Tohoku, and the same or slightly less soluble than normal in the Kanto-Koshin regions.
• Late-maturing varieties (such as Yamada Nishiki) that ripen from late August to early September, will be less soluble than normal when grown in western Japan.

(Source: National Research Institute of Brewing predictions for suitability of this year’s rice for sake brewing (独立行政法人酒類総合研究所令和４年産清酒原料米の酒造適性予測))