What is sake made from?

Sake has one of the shortest ingredient lists of any drink you can order. Four things go in, and the brewer's skill does the rest. Here's what each ingredient is, what it does, and why the details matter for how your sake tastes.

The four ingredients

Ingredient	What it does
Rice	Supplies the starch that becomes sugar, then alcohol. Also shapes body and flavor.
Water	Used to wash, soak, and steam the rice, and makes up most of the finished sake.
Koji	A mold grown on steamed rice. Its enzymes turn rice starch into sugar.
Yeast	Turns that sugar into alcohol and creates many of the aromas.

That's the full list for Junmai sake, the "pure rice" category. Other styles, like Honjozo, Ginjo, and Daiginjo, also add a small, regulated amount of distilled alcohol near the end of fermentation. More on that below.

Rice: not the kind you cook for dinner

Sake can be made from everyday table rice, but most premium sake uses dedicated sake rice. Compared with table rice, sake rice usually has:

• Bigger grains that hold up to heavy polishing without cracking.
• A large starchy core, called shinpaku, which is the part brewers want.
• Less protein and fat, which can otherwise add heavy or rough flavors.

There are dozens of sake rice varieties. A few of the best known:

• Yamada Nishiki: often called the king of sake rice, prized for elegant, aromatic sakes. It's the rice in our Sakura bottle.
• Gohyakumangoku: widely grown in Niigata, known for clean, light, crisp sake. It's the rice in the WESAKE can.
• Omachi and Miyama Nishiki: two more classics, each with its own character.

Before brewing, the rice is polished to remove the outer layers of each grain. How much is left is the polishing ratio, and it's one of the main things that sets sake grades apart. A ratio of 60% means 40% of the grain was milled away. See our polishing ratio guide for what those numbers look like.

Water: the biggest ingredient by volume

Water is easy to overlook, but it touches every stage. Brewers use it to wash, soak, and steam the rice, and it makes up most of the finished sake. That's why breweries are traditionally built near a good, reliable water source.

The minerals in the water matter:

• Harder water, with more minerals, tends to feed the yeast well and give a faster, more vigorous fermentation, often with a firmer, drier result.
• Softer water ferments more slowly and often gives a softer, smoother sake.
• Iron is avoided, because it can discolor sake and affect its flavor.

Different water is one reason sake from different regions can taste so different, even from similar rice.

Koji: the ingredient that makes sake possible

Rice can't ferment on its own. Unlike grapes, it has no sugar to start with, only starch. That's where koji comes in.

Koji is steamed rice that has been inoculated with a mold called Aspergillus oryzae and carefully grown for a couple of days in a warm, humid room. As it grows, it produces enzymes that break rice starch down into sugar. The same mold is used to make soy sauce and miso, and it's considered so important in Japan that it has been named a national fungus.

Koji also adds flavor: a lot of sake's savory umami and gentle sweetness trace back to it. Brewers say making good koji is one of the most important jobs in the brewery.

Yeast: where the alcohol comes from

Yeast eats the sugar that koji makes and turns it into alcohol and carbon dioxide. Sake yeasts are selected strains, and many are numbered and distributed by the Brewing Society of Japan so brewers can choose one that suits their style. Some yeasts give big fruity aromas, others give a quieter, cleaner sake.

Before the main fermentation, brewers grow a large, active population of yeast in a small starter batch called the shubo or moto. That starter then gets added to the main tank with more rice, koji, and water.

How the four come together

Here's what makes sake unusual: the koji turns starch into sugar and the yeast turns sugar into alcohol at the same time, in the same tank. This is called multiple parallel fermentation. In beer, those two steps happen separately: the grain's starch is converted to sugar first, then yeast ferments it.

Because the sugar is released slowly and steadily, sake yeast can keep working for weeks. That's how sake reaches around 15 to 16% ABV naturally, without distillation. Many sakes are then adjusted with water before bottling or canning.

When fermentation is done, the mash is pressed to separate the clear sake from the rice solids (called sake kasu), then it's usually filtered and pasteurized. For every step, read how sake is made.

What about added alcohol?

Some sake styles have a small amount of distilled alcohol added near the end of fermentation. It's not about making the sake stronger. Brewers use it to lift aromas and lighten the texture. In Honjozo, it's capped at 10% of the weight of the polished rice.

If you want sake made only from rice, water, koji, and yeast, look for the word Junmai on the label. That includes Junmai, Junmai Ginjo, and Junmai Daiginjo. Our guide to what Junmai sake is explains the category, and the types of sake shows how all the grades fit together.

What's in WESAKE

The WESAKE can is a Junmai Ginjo, made from four ingredients: rice, water, koji, and yeast. Nothing else added. It's brewed by Kaganoi Shuzo in Itoigawa, Niigata, from Gohyakumangoku rice polished to 60%. It's gluten free, vegan friendly, and has no added sulfites. The result is dry and light, with soft umami and a crisp, clean finish.

See the full ingredient story on our sake page, or start from the beginning with what sake is.