The following is our collection of the best Japanese koji rice brands this 2021. We chose to give you this roundup of delicious rice, which you can use both for fermentation and as rice to pair with your meals. Plenty of our friends, readers, home cooks, and relatives, as well as Japanese chefs and those with good knowledge about fermentation and Japanese alcohol, asked us to create this particular list. They’re mainly interested in the concept of fermentation, while some of them love drinking sake and want to know how to make it.
Fermented food is now growing in popularity, from drinks like kefir and kombucha to hotdog condiments, including sauerkraut and spicy and tangy kimchi. You can find these in grocery stores, restaurants, and even in the homes of many cooks around the world. However, there’s also another fermented cuisine that’s steadily growing in popularity: Koji rice.
Koji rice is a type of cooked rice infused with a mold called Aspergillus oryzae, which you can find in East Asia – Specifically, Japan. This releases enzymes that help ferment the Koji rice. They do this by slowly decomposing the proteins and carbs found in the rice. The same fermentation process also happens to legumes like soybeans and even other grains, such as barley.
To make Koji rice, you need to add the culture into the cooked rice grains. Place the grains inside wooden trays. Then, store it in a humid and warm environment to start the fermentation process. Leave the rice for around 50 hours. The result is usually moldy rice with a somewhat nasty odor, but the smell or look shouldn’t put you off as it tastes good.
The following is an unbiased roundup of the best Koji rice brands that you can ferment today. Unlike previous lists, the group of testers we chose for this one is minimal. Many of them are pro chefs and cooks in distilleries and Japanese restaurants. Since not a lot of Koji rice brands are found outside Japan, we didn’t have any difficulty in narrowing down our selection. All of these Koji rice brands come from a variety of food manufacturers. We measured the advantages and disadvantages of each of these rice brands, so you’ll know which one is the best. Plus, to create the list below, we had to measure the rice according to its price, the taste of the finished product, and the size of its bag or box.
Best Koji Rice Comparison & Rating
| Image | Koji Rice | Rating |
|---|---|---|
 | #1 - Isesou Miyako Koji | 99% |
 | #2 - Marukome Nama Shio Koji | 97% |
 | #3 - Rhapsody Natural Foods Organic Sweet Miso Koji | 96% |
![Rice koji (dry type) 300g [factory direct] [handmade Amakoji, to Shiokoji-sweet sake, miso]](https://images-na.ssl-images-amazon.com/images/I/51XmB0ii5kL.jpg "Rice koji (dry type) 300g [factory direct] [handmade Amakoji, to Shiokoji-sweet sake, miso]") | #4 - Komirona Rice Koji | 94% |
 | #5 - Marukura Rice Koji | 91% |
 | #6 - Horaiya Nama Koji | 90% |
 | #7 - Hanamaruki Liquid Shio Koji | 90% |
 | #8 - Rhapsody Foods Organic Barley Koji | 88% |
 | #9 - Natural Health Company Shiokoji | 87% |
According to experts and the opinions of our testers, here’s our collection of the top nine Koji rice brands this year:
#1 – Isesou Miyako Koji
This is a common brand of Koji rice. Isesou Miyako Koji rice comes in dozens of sizes, so much that we initially thought that this was the only brand of Koji rice they had in the market. Koji is made by growing Koji kin on top of grains like soybeans, wheat, and rice. It’s often used as a type of raw material, which is an essential ingredient in traditional Japanese cuisine. This includes soy sauce, sake, sweet sake, and pickled vegetables as an accompaniment to sushi.
The dried version of Koji is called Miyakokoji. This type of Koji rice dries at lower temperatures, so the traits of the original Koji rice are kept for as long as they possibly could. If you have Koji rice at the moment, then you can learn how to make shio Koji on your own. Meanwhile, the miso from the same product is excellent for making miso sauce, or some warm and comforting miso soup. Adding pepper and salt with the Koji rice for preserving can cause the flesh of the fish and meat to be tender and delicious.
What We Like About It:
Our tester attempted to use Koji for seasoning his food, instead of the usual salt and pepper combo. He placed it on his steak. He admits that it wasn’t the traditional use of Koji rice, but he covered the slab of sirloin with the rice for two whole days and left it in the fridge. After grilling it outside his home, he ended up eating what he calls a “poor man’s aged steak,” Before covering his steak with it, he initially ground up the Koji rice and used it as a coating. A helpful tip would be to check airflow before you ferment it and place it on top of your grill. The steak ended up tasting delicious (with a hint of nutty flavor) and was also very tender to chew on.
#2 – Marukome Nama Shio Koji
This is a type of Marukome rice malt seasoning, also known as shio Koji. The product weighs 7 ounces and comes in a pouch. Unfortunately, unlike our previous entry, this particular shio Koji cannot be used as a way to preserve fish or steak. It is still a marinade, so when you use it, its enzymes will start building up as time goes on. You can even use this product for making things such as miso paste, and combine it with other methods. If you want to dry-age your fish or beef, then purchase regular fermented Koji rice instead.
This is unpasteurized Koji rice, although there is a bit of alcohol in it, which helps it ferment further. The rice is also surprisingly edible even after you rinse it off the meat or fish. Your body will not react after eating a tiny bit of shio Koji. But keep in mind that meat or fish that you marinate in this product does brown up quickly, so be sure to keep an eye on your food. This is due to the sugars and enzymes found on top of the meat.
What We Like About It:
Our tester just dipped his toes into the interesting world of Japanese cuisine. And one of the cookbooks he purchased had a lovely recipe for shio Koji pork chops. He searched high and low in his grocery for some Koji rice and even traveled to Chinatown just to check if there’s any. Unfortunately, there weren’t any. Luckily he was able to purchase some online, and he ended up buying two packs of this product. The pork chops that he grilled were some of the most flavorful ones he’s ever tried, and he used the product to marinate it for three days.
#3 – Rhapsody Natural Foods Organic Sweet Miso Koji
Koji is a type of polished and steamed rice that infuses with a mold called Aspergillus oryzae. This is known for creating the fermentation process of both Koji rice (also known as amazake) as well as miso (miso rice or barley Koji), among other types of fermented Japanese food. Rhapsody Natural Foods’ Koji rice comes with directions, in case you’re fermenting Koji rice for the first time.
According to experts in Koji rice, the product can have 3 main uses. The first one is for making rice milk or amazake, in which you can use amazake Koji. The second is miso, which calls for sweet miso Koji. The third is red miso, which requires barley Koji that has a longer fermentation process. For marinating meat, fish, or even vegetables, then you can go for any type of Koji. This is good because all of them contain a powerful enzyme, which can help break down carbohydrates, fats, and protein. However, each of these Koji types has a subtle difference in regards to flavor. This is due to the proportions in which the enzymes can start working on the kind of Koji you choose. The color of the finished product will result from white to pale yellow or earthy green.
What We Like About It:
Our tester just so happened to purchase some ribeye steaks from the local supermarket. She intended to marinate steaks in this product and grill them after 2 days. However, because of her busy schedule, 2 days ended up becoming 2 weeks instead. One of the first things that she noticed after rinsing off the Koji from the steaks was that they sported a weird brown color, instead of red. They were much lighter as well. After grilling, she learned that it enhanced the natural flavors of the beef. She told us that this is the way she’ll be cooking her steaks from now on.
#4 – Komirona Rice Koji
If you can find this particular product in your grocery or supermarket, then you can be sure that it’s a direct import from Japan. You can use Komirona’s rice Koji to make your own sake. You can also ferment it to create barley Koji or shio Koji. This is the drying grain type of Koji rice and has been vacuum-sealed to ensure its freshness. It weighs 300 grams. To ferment it, just add 500 milliliters of water. The product is gluten-free and GMO-free.
Feel free to bring this fantastic Japan import into your home, and create the most delicious Japanese drinks and dishes with it. It’s perfect for shio Koji, barley Koji, miso, sake, shochu, as well as vinegar, pickled vegetables, and soy sauce. It’s a great and brand new way to ferment your food. As mentioned, the rice is a dry-grain type. This is great when it comes to storage stability, and has a nice weight to it. Fermenting Koji rice is so easy; even a beginner can do it. The package is vacuum-sealed to ensure freshness. You can store it for a long time inside room temperature, no matter if it’s fermenting or dried.
What We Like About It:
Our tester used this Koji rice to tenderize her steak, and it worked amazingly. To try it out, she picked a tough cut of meat from her supermarket, rubbed the Koji rice on top, and placed it in the fridge for about a week. The finished product was delicious, and she even claims that it tastes better than high-grade Wagyu beef. Her purchase was worth it.
#5 – Marukura Rice Koji
This is dried Koji rice. It is also organic and healthy. You can use this to make authentic Japanese sake, miso, or soy sauce. Ingredients include rice. As much as possible, try to use this right away after opening the bag, as the product expires in around six months. The product weighs about 500 grams. Do not place the rice under direct sunlight during the fermentation process and store it at room temperature instead. The rice can produce delicious sake or shochu after fermenting it for eight hours.
What We Like About It:
Unfortunately, our tester thinks that this particular Koji brand is weaker compared to the ones that he purchases in American groceries. This is probably due to the shipping expenses. The rice grains were also cracked in half, and he knows that Koji rice has shorter grains. He never really told us if he used this product to marinate steak or to make sake or miso paste.
A second tester had better luck. She used this to marinate chicken breasts and salmon steaks that she wanted to grill. The Koji rice helped bring the flavors up a notch, and brought out that amazing umami flavor that’s usually hard to replicate. She’s only tried it twice so far, but she thinks that it works best for non-veggie based dishes. Her husband ordered two more online, so they’ll always have Koji rice in stock in case they want to cook some chicken again.
#6 – Horaiya Nama Koji
The type of Koji rice used in Horaiya’s product is known as nama Koji or dried Koji. Nama Koji dries at low temperatures, so it preserves the Koji rice’s characteristics. This product lets you create both shio Koji and miso Koji. It’s perfect for both beginners and experts. It’s also an excellent way for you to preserve your meat, including poultry, fish, and chicken.
Koji rice is a fermented product, so it has its own set of health benefits too. For one, it can help clean your intestines, aid digestion, and regulate your heart’s blood flow. Aside from that, some Japanese people believe that eating dried Koji rice that’s been soaked in one teaspoon of water (cold or hot) after a meal can be good for you. It is rich in amino acids and can regulate blood pressure.
What We Like About It:
It works pretty great as a Koji starter. Our tester used 50 grams of this product to make a kilo of Koji rice. Then once the rice was done, he used it to create roughly 200 grams of shio Koji. It does take a lot of work, especially since he makes it all by himself, but it still saves him cash. He says that the products give him excellent molds each time.
#7 – Hanamaruki Liquid Shio Koji
Shio Koji, also known as salt Koji, is a combination of water, salt, and Koji itself. Koji is a natural seasoning that works as both a tenderizer and a marinade for meats. It brings out the umami flavor of food. Koji only contains natural flavors, and there are no chemicals found in it either. It is filled with enzymes that help break down the protein and starches inside the food.
Hanamaruki’s own liquid shio Koji is not heat-treated, but still contains the same enzymes that you can find inside regular Koji. The proteins can neutralize the rich scent coming from raw meat while it cooks, and enhance the texture by tenderizing it. Hanamaruki is the only company where the Koji comes in pure liquid form. They place regular shio Koji inside a sake bag. Then, they extract it to acquire the liquid.
What We Like About It:
This is impressive stuff. Our tester thinks the taste is very subtle, but it gets so much better when you use it on food, especially meat. This is an excellent recommendation for use as a marinade for poultry, fish, or meat. You can even use it on vegetables because it’s liquid. Our tester added it to his salad dressing.
#8 – Rhapsody Foods Organic Barley Koji
Barley-based Koji is polished rice incorporated with Aspergillus oryzae culture. The same product is responsible for the fermenting of drinks like amazake, barley-based miso paste, sake, rice miso, and others. Barley Koji is different from Koji rice when it comes to flavor.
Rhapsody Natural Foods is a company that continues to grow. Their products are available in online stores, distributing them to countries outside of the US. All of their products are kosher, including the barley Koji.
What We Like About It:
Our tester was delighted when she used this type of Koji. Practically every rice grain has an excellent coating, and the mold that they used fermented it quickly. She didn’t have issues making sake or miso paste and even used a bit of the product to age a steak. She couldn’t wait to try out this product again and use it on other dishes.
#9 – Natural Health Company Shiokoji
Usually, Koji rice comes from white rice, but there are instances when brown rice is used here as well. Koji rice is excellent as a raw or fermented material used in seasonings and traditional Japanese cuisine. Some of the foods made with Koji rice go back to ancient times. The fungus that helps Koji rice ferment is considered to be endemic to Japan, so the fermentation of the rice is excellent. It replicates the effects of yeast and lactic acid bacteria.
Brown rice Koji is also great for minerals, vitamins, as well as other important dietary fiber. The mold that is involved in creating brown rice Koji takes plenty of work. Once the mold incorporates itself into the rice, you now have to store in room temperature, as bacteria will rely on the perfect temperature to begin their fermentation work.
What We Like About It:
Initially, our tester thought this product is the brand that Japanese restaurants use to make sake. However, this is mainly used as meat flavoring. He then started experimenting on how to marinate some meat with the product. The flavor of his chicken was good, while his steak tasted as if it has been dry-aged by a professional. It was quite tender, too.
As you can see, nearly all of our testers have nothing but the best words to say about this excellent product.
Do You Need Koji Rice?
In some Japanese homes, fermented Koji rice is used as a substitute for salt when preserving food. You can simply swap in two teaspoons of Koji rice (in this case, the rice is referred to as shio Koji, with shio translating to ‘salt’) with a teaspoon of salt in case the recipe calls for it. Koji rice is also great for marinating pickled veggies, fish, and some types of meat. Others will even use it as a soy sauce substitute.
Koji rice is a significant component in plenty of Japanese dishes. So if you have plans on learning how to make delicious Japanese food or Japanese alcohol like shochu and sake, then yes, Koji rice should be a staple in your kitchen. Its fermented version can add a bit of flavor to Japanese pantry ingredients such as soy sauce and miso paste.
Another advantage of Koji rice is that it’s so healthy; it usually ends up passing their nutrients to the food it’s mixed in because they ferment along with the rice itself. Plus, fermented food is said to improve one’s digestive and immune system.
Koji salt is filled with a flavor called umami, which is gaining popularity among home cooks and chefs, incorporating them into everyday dishes, even non-Japanese ones. You can produce an umami flavor when you combine together water, salt, and Koji rice, then leave it to ferment for several weeks at room temperature. The rice transforms into a lumpy and thick paste, with a combined taste of miso and salt.
So now that you’re familiar with the concept of Koji and Koji rice, why don’t you choose a brand from this list and try it out yourself? We’re certain that you’ll be wowed by it too.