Brewing · Guide

How to Make Sake at Home

A step-by-step guide to brewing sake at home. Covers rice selection and polishing, koji cultivation, building the moto yeast starter, moromi main mash, multiple parallel fermentation, pressing, and aging.

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Sake served beside koji rice and a rice-mash ferment

Updated August 2026 · 15 min read

Sake is one of the most refined fermented beverages in the world, and it is entirely possible to brew it at home. The process is different from beer or wine because it relies on a mold called koji (Aspergillus oryzae) to convert rice starch into fermentable sugar. This conversion happens simultaneously with yeast fermentation in the same vessel, a process called multiple parallel fermentation. The result is a smooth, aromatic beverage that can reach 18-20% ABV naturally, higher than any other fermented drink. The process takes patience and attention, but no specialized equipment beyond a basic homebrewing setup.

Understanding how sake fermentation works

Sake sits in a category of its own among fermented beverages. Beer brewing converts grain starch to sugar in a separate mashing step, then ferments the sugar with yeast. Wine starts with grape juice that already contains sugar, so yeast goes straight to work. Sake does something neither can: it converts starch to sugar and sugar to alcohol at the same time, in the same container.

18-20% ABV achieved through parallel fermentation
40-48 hrs Time to grow koji rice from spores
18-32 days Moromi (main mash) fermentation period

The agent responsible for starch conversion is koji, the mold Aspergillus oryzae. Koji produces enzymes (amylases and proteases) that break rice starch into glucose. Yeast then ferments that glucose into alcohol and CO2. Because the koji continuously feeds new sugar to the yeast, fermentation never stalls from sugar depletion the way beer or wine can. This steady supply of fresh glucose is why sake achieves such high ABV levels without distillation.

Koji beyond sake Aspergillus oryzae is the same mold used to make miso, soy sauce, mirin, and rice vinegar. It has been cultivated in East Asia for over a thousand years and was designated Japan s national mold (kokkin) in 2006. Working with koji connects you to one of the oldest fermentation traditions in human history.
Sake is not rice wine Despite being commonly called rice wine, sake is produced by a brewing process, not a winemaking process. Wine ferments fruit sugar directly. Sake requires an enzymatic starch conversion step, which is structurally closer to beer brewing. The correct English term is "rice beer" or simply "sake."

Choosing and preparing your rice

The rice you select and how you prepare it shapes the final character of your sake. Japanese sake breweries use specialized sake rice (sakamai) varieties with large, starchy centers and low protein. Homebrewers have more affordable options that still produce excellent results.

Yamada Nishiki The most prestigious sake rice variety, grown primarily in Hyogo Prefecture. It has an exceptionally large shinpaku (starchy core) and low protein content. Available from specialty homebrew suppliers at a premium price. Use this if you want the smoothest, most refined sake.
Calrose medium-grain rice Widely available at grocery stores and a practical choice for homebrewers. Calrose is a California-grown medium-grain rice that produces clean, balanced sake. It costs a fraction of Yamada Nishiki and delivers strong results for a first batch.
Other medium-grain options Kokuho Rose, Nishiki, and other medium-grain Japanese-style rice varieties all work well. The grain should be short to medium in length, starchy, and slightly sticky when cooked. Avoid long-grain rice like jasmine or basmati, which lacks the right starch structure.

Rice polishing (seimai) is the process of milling away the outer layers of each grain to remove proteins, fats, and minerals that cause off-flavors. Commercial sake rice is polished to specific ratios: Junmai sake uses rice polished to 70% or less of its original size (30% or more removed). Daiginjo-grade sake polishes down to 50% or less.

For homebrewers You probably cannot polish rice at home, but pre-polished sake rice is available from homebrew suppliers at 60% and 70% seimai-buai (polishing ratio). Alternatively, standard Calrose rice from the grocery store has been commercially milled to roughly 90-92% of its original size, which is enough to produce good sake. The more you polish, the cleaner and more delicate the final flavor.
Washing and soaking Rinse your rice thoroughly under cold water until the water runs clear, typically 5-8 rinses. This removes surface starch that would make the rice gummy when steamed. After washing, soak the rice in cold water for 30-60 minutes (less time for more polished rice, which absorbs water faster). Drain completely before steaming.

Watch for

  • Do not cook your rice in a rice cooker or pot. Sake rice must be steamed, not boiled. Boiled rice absorbs too much water and becomes mushy, which prevents proper koji growth and fermentation.
  • Over-soaked rice falls apart during steaming. Highly polished rice (60% or less) should soak for only 5-15 minutes. Standard Calrose needs 30-60 minutes.

Growing koji: the heart of sake brewing

Koji-making (seigiku) is the most labor-intensive step in sake brewing and the one that most determines the quality of your finished sake. You are cultivating a living mold on steamed rice, and the mold needs consistent temperature and humidity to thrive.

  1. 1
    Steam your rice Steam 2-3 cups of washed and soaked rice in a steamer basket or colander lined with cheesecloth, set over a pot of boiling water. Steam for 45-60 minutes until the grains are firm on the outside but fully cooked through. The rice should hold together when squeezed but not be mushy or wet.
  2. 2
    Cool to inoculation temperature Spread the steamed rice on a clean baking sheet or tray in a thin layer. Let it cool to about 95-100 degrees F (35-38 degrees C). Work quickly to prevent the surface from drying out. You can fan it gently to speed cooling.
  3. 3
    Inoculate with koji spores Sprinkle koji-kin (Aspergillus oryzae spores) evenly over the rice. Use about 1/4 teaspoon of spore powder per 2 cups of dry rice. Mix the spores into the rice thoroughly with clean hands, making sure every grain gets contact with the spore powder. Even distribution is more valuable than the exact amount.
  4. 4
    Incubate at 86-95 degrees F (30-35 degrees C) Transfer the inoculated rice to a shallow covered container (a casserole dish with a lid or a tray wrapped in damp towels). Place it in your incubation setup. Options include an oven with only the light on, a cooler with a seedling heat mat, or a dedicated fermentation chamber. The target temperature is 86-95 degrees F (30-35 degrees C) with high humidity.
  5. 5
    Monitor and mix Check the rice every 8-12 hours. After 12-18 hours, you should see white fuzz beginning to form on the grains. Gently mix the rice to redistribute heat and moisture at the 18-24 hour mark. The mold generates its own heat as it grows, so monitor temperature closely. If it climbs above 104 degrees F (40 degrees C), open the container briefly to cool it.
  6. 6
    Harvest at 40-48 hours Finished koji rice should be covered in a uniform white mold, feel slightly firm and dry on the surface, and smell sweet and chestnut-like. The grains will be bound together by the mold and may need to be gently broken apart. Refrigerate immediately to stop further growth. Use the koji within 2-3 days, or freeze it for longer storage.
Shortcut: buy pre-made koji If growing koji from spores feels too daunting for your first batch, buy cold-dried koji rice from a Japanese grocery store or online supplier. Brands like Cold Mountain, Gem Cultures, and Miyako Koji are widely available. Pre-made koji works well and lets you focus on learning the fermentation process.
Signs of bad koji Green, black, or yellow mold indicates contamination with the wrong Aspergillus species or other molds. Throw it out and start over. Good koji is white to very pale yellow only. A sour or musty smell (rather than the characteristic sweet, chestnut aroma) also indicates problems.
Hydrometers comparing wort and finished beer samples

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Building the moto (yeast starter)

The moto (also called shubo) is the yeast starter for your sake. It builds up a large, healthy yeast population in a small, concentrated mixture of koji, steamed rice, water, and yeast. The moto also develops the lactic acid environment that protects the fermentation from contamination.

  1. 1
    Combine the ingredients In a sanitized half-gallon jar or small food-grade container, combine 1/2 cup koji rice, 1 1/2 cups freshly steamed and cooled rice, and 1 cup of cold filtered water. Stir well. The mixture will be thick and porridge-like.
  2. 2
    Pitch your yeast Sprinkle sake yeast (Wyeast 4134 or White Labs WLP705 are common homebrew options) over the surface and stir in. If you cannot find sake yeast, a clean wine yeast like Lalvin EC-1118 works as a substitute and tolerates the high alcohol levels sake reaches.
  3. 3
    Add lactic acid Add 1 teaspoon of food-grade lactic acid (88% concentration) to the moto. This is the sokujo (quick) method used by most modern sake breweries. The acid drops the pH to around 3.5-4.0, creating an environment hostile to bacteria but comfortable for yeast. The traditional yamahai and kimoto methods develop lactic acid naturally over 4 weeks, but the sokujo method is faster and more reliable for homebrewers.
  4. 4
    Ferment the moto Cover loosely and place in a cool area at 60-65 degrees F (16-18 degrees C). Stir once or twice daily. Over 7-14 days, the mixture will begin to bubble gently and develop a sweet, fruity aroma. The liquid will separate from the solids and become slightly milky. The moto is ready when it smells clean and alcoholic, with active bubbling.

The moromi: main mash and parallel fermentation

The moromi is the main sake mash where parallel fermentation happens. You build the moromi by adding steamed rice, koji, and water to the moto in three stages over four days. This gradual building process (called san-dan-jikomi, or three-stage addition) keeps the yeast concentration high relative to the sugar supply, preventing contamination and ensuring steady fermentation.

  1. 1
    Day 1 - Hatsuzoe (first addition) Transfer the finished moto to your main fermentation vessel (a 2-3 gallon food-grade bucket or carboy works well). Add 1 1/2 cups koji rice, 2 1/2 cups steamed and cooled rice, and 2 1/2 cups cold filtered water. Stir well. The mixture roughly doubles in volume from the moto.
  2. 2
    Day 2 - Odori (resting day) Do not add anything. Let the yeast catch up to the new food supply. Stir once or twice during the day. You should see active bubbling as the yeast multiplies into the new rice. This rest day is important for maintaining a healthy yeast population.
  3. 3
    Day 3 - Nakazoe (second addition) Add 2 cups koji rice, 4 cups steamed and cooled rice, and 4 cups cold filtered water. Stir well. The volume roughly doubles again. Fermentation should pick up noticeably within a few hours.
  4. 4
    Day 4 - Tomezoe (third and final addition) Add 2 1/2 cups koji rice, 6 cups steamed and cooled rice, and 6 cups cold filtered water. Stir well. This is the largest addition and brings the moromi to its full volume. Cap the vessel with an airlock.
  5. 5
    Days 5-25+ - Active fermentation Ferment at 50-60 degrees F (10-16 degrees C) for 18-32 days. Lower temperatures produce a more refined, aromatic sake but take longer. Higher temperatures speed fermentation but can produce rougher, less nuanced flavors. Stir daily for the first week, then every 2-3 days after that. The moromi will bubble actively and develop a rich, fruity, floral aroma.
Temperature matters Professional sake breweries ferment their premium grades (Ginjo and Daiginjo) at temperatures as low as 46-50 degrees F (8-10 degrees C) for 30+ days. This slow, cold fermentation produces delicate fruity esters (especially the apple-like ethyl caproate and banana-like isoamyl acetate) that define high-quality sake. If you can maintain cold temperatures, do so.
Tracking progress The moromi will slowly thin from a thick rice porridge to a soupy liquid as the koji breaks down the rice. Take specific gravity readings every few days. Sake finishes between 0.990 and 1.000 on a hydrometer (negative Brix on a refractometer). When gravity stabilizes over 2-3 consecutive readings, fermentation is complete.
The quantities above are guidelines Different sources use slightly different ratios. The general principle is consistent: build the mash in three additions of increasing size, with a rest day between the first and second addition. Total rice (including koji) should be roughly 6-8 pounds for a 1-1.5 gallon batch of finished sake.

Watch for

  • Do not skip the rest day (odori). Adding too much rice too fast overwhelms the yeast and invites bacterial contamination.
  • Keep the moromi covered and airlocked after the final addition. Oxygen exposure at this stage encourages Acetobacter, which produces vinegar-like off-flavors.
  • If fermentation stalls and gravity stops dropping, the temperature may be too cold. Move the vessel to a slightly warmer location (55-65 degrees F / 13-18 degrees C) and stir vigorously to resuspend the yeast.

Pressing, pasteurizing, and aging

Once fermentation is complete, you need to separate the sake from the rice solids (called kasu or lees). This pressing step is called joso in Japanese.

  1. 1
    Press the sake Pour the moromi through a fine-mesh straining bag (a nylon paint strainer bag or purpose-made sake pressing bag) suspended over a clean container. Let gravity do most of the work for 4-8 hours. Then gently squeeze the bag to extract the remaining liquid. Do not squeeze too aggressively, which forces starchy sediment into the sake and makes it cloudy.
  2. 2
    Settle and rack The pressed sake will be cloudy with fine sediment. Refrigerate it in a sealed container for 5-10 days. The sediment (ori) will settle to the bottom. Carefully siphon (rack) the clear sake off the sediment into a clean container, leaving the cloudy dregs behind.
  3. 3
    Pasteurize (optional) Most commercial sake undergoes pasteurization (hi-ire) to stabilize flavors and kill remaining enzymes and yeast. Heat the sake to 140-150 degrees F (60-65 degrees C) in a water bath, hold for 5-10 minutes, then cool quickly by placing the container in ice water. Unpasteurized sake (namazake) has a fresher, livelier flavor but must stay refrigerated and should be consumed within a few weeks.
  4. 4
    Age or drink Freshly pressed sake is drinkable immediately, with a bright, young, and sometimes rough character. Aging for 2-6 months in a sealed container in the refrigerator smooths the flavors and integrates the alcohol. Some sake benefits from up to a year of cold aging. Commercial sake is typically aged for 6 months before release.
Nigori (cloudy sake) If you prefer cloudy sake, skip the settling step or use a coarser straining material. Nigori-style sake retains some of the rice sediment, giving it a creamy, milky appearance and a richer, sweeter flavor. It is a popular style for homebrewers because it requires less processing.
Dilution Undiluted homebrew sake (genshu) typically finishes at 17-20% ABV. Commercial sake is usually diluted with clean water to 14-16% ABV before bottling. Taste your finished sake at full strength and then try adding filtered water in small increments until you find your preferred balance of flavor and alcohol intensity.
Storage Store finished sake in sealed glass bottles in the refrigerator. Sake does not improve indefinitely like wine. Most styles are best consumed within 6-12 months of pressing. Keep it away from light and heat, which accelerate flavor degradation. Dark glass bottles help if refrigerator space is limited.

Brewing sake at home is a different discipline from beer or wine. The process demands more hands-on attention, especially during koji cultivation and the moromi building phase. But the reward is a beverage you cannot easily replicate with any other fermentation technique. Start with pre-made koji and Calrose rice for your first batch. Once you have the process down, grow your own koji and experiment with polished sake rice for a more refined result. Each batch teaches you something about the relationship between the mold, the yeast, and the rice.

FAQ

Frequently asked questions

How long does it take to make sake at home?
Plan for about 5-7 weeks from start to finish. Koji cultivation takes 2 days. The moto (yeast starter) develops over 7-14 days. The moromi (main mash) ferments for 18-32 days. Pressing, settling, and pasteurizing add a few more days. Some homebrewers age their sake for an additional 2-6 months for smoother flavor, but you can drink it young.
What rice should I use for homebrew sake?
The gold standard is Yamada Nishiki, a Japanese sake rice with a large starchy core and low protein. It is available from specialty homebrew suppliers. Calrose medium-grain rice, widely available in grocery stores, produces good results at a fraction of the cost. Avoid long-grain rice like jasmine or basmati, which has too much surface starch and the wrong grain structure for sake.
Do I need special equipment to brew sake?
You need a large pot for steaming rice, a fermentation vessel (food-grade bucket or carboy), a thermometer, a fine-mesh straining bag for pressing, and basic sanitizing supplies. The most unusual requirement is an incubation setup for growing koji, which can be as simple as an oven with the light on, a cooler with a heating pad, or a dedicated fermentation chamber. No specialized equipment beyond a standard homebrewing kit is required.
What is multiple parallel fermentation?
Multiple parallel fermentation is the process that makes sake unique among fermented beverages. In beer, starches are converted to sugars during mashing, and then yeast ferments those sugars separately. In sake, koji mold breaks down rice starch into glucose while yeast simultaneously ferments that glucose into alcohol, all in the same vessel at the same time. This parallel process allows sake to reach ABV levels of 18-20%, far higher than beer or wine.
Can I use store-bought koji rice instead of growing my own?
Yes. Cold-dried koji rice (available from Japanese grocery stores and online suppliers like Cold Mountain or Gem Cultures) works well for homebrewing and saves you the two-day incubation process. Using pre-made koji is a good strategy for your first batch. Once you understand the overall sake process, growing your own koji from spores gives you more control over enzyme activity and flavor.
How strong is homemade sake?
Undiluted homebrew sake typically finishes at 17-20% ABV, which is stronger than commercial sake that has been diluted with water to 14-16% ABV before bottling. You can dilute your finished sake with clean, filtered water to bring it down to your preferred strength. Many homebrewers prefer the undiluted version for its richer, more concentrated flavor.
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