Sometimes, two different types of rice are used to brew one label. Each brewery has their particular recipe to differentiate themselves to the others.
To make use of 2 different rice, they don’t just mix them and process. Each rice has own characteristic so that the processing of rice has to proceed separately.

KOJIMAI
Usually, rice is used twice in the brewing process. One is producing Koji, which is a necessary step for converting starch to glucose. The rice used for this process is called Koji mai(Koji rice).
The other is called Kake mai(Kake rice). In the last brewing step, Moromi production, Kake mai is used. Kake mai is just the steamed rice and thrown into the barrel to proceed the fermentation.

KAKE MAI
Also, sometimes, Sake is produced with the same brewer’s rice but the polish rate is different between Kake mai and Koji mai. It’s also the special recipe of each brewery.
Please take a look at the label. If two different rice is mentioned there, let’s try to guess how they used two different rice!
LABEL DESCRIBING KAKEMAI AND KOJIMAI