Raw materials for sake brewing
Four ingredients are important for the brewing of Japanese sake – rice, koji mold, yeast and water. Each of them is irreplaceable and has its place. In the same way, every manufacturer cares about their quality. For faster orientation in the page, use our infographics, with the help of which you will move faster to the item of your choice.
Rice - 米
Specially bred rice is used for the production of sake, which differs in grain structure from rice used in the kitchen. Sake brewing rice is specially bred to concentrate the starch in the grain in the middle. Therefore, this rice shows a white dot in an otherwise milky grain. This white core is called shinpaku 心 白 / し ん ぱ く in Japanese. This center is the most important for the production, because this starch is turned into sugar with the help of the koji fungus, which the yeast can then process into alcohol.
When growing rice, it is important where it is grown. Each prefecture is more suitable for different rice types and the so-called local varieties also develop accordingly. Today, they are gaining strength and a new generation of brewers is looking for them to differentiate themselves from their predecessors. At the same time, ecology comes into play, where the effort is to work with rice, which will grow in the place where sake is brewn. Rice harvest always starts in September and it lasts until the end of October or as the weather allows.
The most commonly used variety is Yamada Nishiki. This variety was specially bred due to its height and grain size. It is easy to grow and harvest.
Other popular varieties are Gohyakumangoku, Omachi, Miyama Nishiki or Dewa San San.
Koji mold - 麹菌
Molds are used in Japan to make both alcoholic beverages and soy sauce or miso paste, which is used for popular soup. In latin this specific mold is called Aspergillus oryzae. It is a fungal mold that feeds on starches and converts them into simple sugars, which then are turned into alcohol by the yeast. Three types of this mold are mainly used for the production of alcoholic beverages – yellow (A – sake), black (C – shochu and awamori) and white (E – shochu).
Yellow Koji – This mold is used in the production of sake. It is sensitive to temperature and at higher temperatures can cause acidification during fermentation. That is why sake has traditionally been produced mainly over the winter. Today, fermentation vats are in temperature-controlled rooms, so this property can be used and a certain degree of acidity can be added to the sake so that the resulting sake is not too sweet.
Black Koji – is a previously discovered fungal mold that is used in the production of shochu, which is a distillate. Shochu can be made from many ingredients, most typically from barley or sweet potatoes. The manufacturers say that it best extracts the taste from the raw material used, which is then transferred to the final product by distillation.
White Koji – sometimes known as Aspergillus kawachii, after the surname of the scientist who first described it. It differs from black mainly in the speed with which it converts starches into sugars and also in the ease of cultivation. At present, most of the shochu is made with its help.
Yeast - 酵母菌
Yeast does need no introduction. Saccharomyces Cerevisiae – alcoholic fermentation yeast – is used for the production of sake. Mankind became acquainted with them a long time ago and they are used in the fermentation of raw materials for almost every type of alcohol you can think of.
But they also play a special role in sake. They create the aroma that the resulting sake will have. There are laboratories in Japan where you can buy yeast according to the catalog. Depending on what you buy, your resulting sake will have that aroma and taste. Yeast are most often named by a number. For example, #7 is the most common yeast used in production. Subsequently, there are also variants, such as #701, where 01 means that the yeast does not form lots of foam on the surface during fermentation. This makes it easier to clean the fermentation vats.
Water - 水
The last and no less important raw material. Historically, most sake breweries were built by a water source because water is important in all steps of production. Today, most sake breweries have their source. Water from this source is further treated to make the best possible chemical composition.
It is most important that it does not contain iron, as this will cause the sake to darken and affect its taste and smell. Another undesirable element is manganese. When the sake is exposed to sunlight, especially ultraviolet light, it changes. It ceases to be clear and loses glare.
On the contrary, suitable elements are potassium, magnesium and phosphoric acid. All these substances help the yeast to multiply faster and the Koji fungus also likes them. And not just during fermentation. Rice absorbs water even during washing and part of the water remains in it even after cooking, and that is good, because this water creates a pleasant environment for its multiplication.