Shochu is another alcoholic beverage imported directly from Japan. The difference between Japanese sake and Shochu is that Japanese sake is categorized as brewed liquor, but Shochu is categorized as distilled liquor.
The process of how Shochu is made
The steaming process of the rice helps to dissolve the rice starch easier and will also provide a sterilizing effect.
Koji is made by sprinkling koji-kin(Aspergillus oryzae) a special natural mold on the steamed rice that has been cooled down between 35°C and 40°C . Koji-kin is used in shochu and sake production to break down the starches in steamed rice into fermentable sugars. It takes about two days to make koji.
Yeast for shochu
Yeast is a microorganism that converts sugar into alcohol. There are specific types of yeasts for shochu just as there are specific types of yeasts for Japanese sake. The choice of the yeast will give a variety of the taste, fragrance, and profile to the shochu.
Moromi for sho
Moromi is the mash in where the process of sugar into alcohol takes place. Shochu requires two preparations of moromi. The first batch of moromi is fermented with koji, water, and yeast. Then the crushed sweet potato has to be mixed together with the first moromi, creating the second fermentation, a step called the second moromi. the people working on making shochu(Kurabito) need to check the fermentation process and temperature constantly once an hour.
There are two kinds of distillation machines. One is used for single distillation and the other one is intended for consecutive distillation. Single distillation is a very traditional distilling method and is used for making “otsu-rui” shochu that is known as ” Real-thing shochu ” (Honkaku-shochu.) Any Shochu made with raw material is recognized as “otsu-rui,” meaning that the product has to be made with the single distilling method.
The consecutive distilling method removes any components without alcohol and results in a product with a high degree of purity. This kind of shochu is called “ko-rui” shochu and it is very close to being both tasteless and odorless.
Storage & Aging for Shochu
A stable quality shochu is usually stored for a while. The first 3 to 6 months will eliminate the component that produces a gas smell. After 6 months to 3 years, the quality of the shochu will be mild since various aroma components will be produced through diminished chemical reaction. After 3 years, the shochu will have a unique flavor because the aroma component is condensed. This “aged shochu” is often stored in a kame (a type of jar) which can be made of earthenware, glass or stone. The kame has no handle. Placing shochu into the kame will make the shochu taste mild because of the many pores on the surface of the storage vessel.
Addition of water
The original shochu (genshu) has an alcohol level of 44-60%, so water will be added to reduce the alcohol content to approximately 24-25% for otsu-rui shochu and 35-36% for ko-rui shochu. Ko-rui shochu has a higher alcohol content than otsu-rui shochu because it is usually mixed with other beverages to make cocktails.
Shochu is made with several raw ingredients and is usually produced in warmer regions like the southern area of Japan. bellow is the shochu ingredients reference map.