Among the alcohol in Japan, you might find nigori sake and doburoku, which have a cloudy color to them. Of the two, nigori is the one that can be called Japanese sake (or refined sake). The reason for this is because the definition of Japanese sake is ‘Ones that have been fermented with rice and filtered’. Doburoku is produced without filtering, but does use a coarse sake straining bag which does leave a murky look. Nigori sake and doburoku make it easier for the sweetness of the rice to remain in the sake. Clear Japanese sake with a refined flavor is nice, but how about some nigori sake every now and again?

Referral information for nigori sake

https://www.japantimes.co.jp/life/2000/04/27/food/nigorizake-puts-the-fun-back-in-sake-drinking/#.XbZf70X7RBI