Japanese Natto Starter Spores (Nattomoto) - 3g (enough to make 30kg of natto). 100% Organic Soybean Extract. 100% Product of Japan

Very happy with this Japanese Natto Starter Spores. It was easy to use and produced authentic, sticky natto with great flavor and texture. I like that a very small amount can make a large batch, so it lasts a long time and is very economical. The instructions were simple enough to follow, and the fermentation worked consistently as long as everything was kept clean and right temperature. Highly recommended for anyone interested in making fresh homemade natto at home.

I was hesitant to use this because I had success making natto from premade frozen natto that I bought from the store and didn't want to take any chances making a bad batch. However, I ran out of frozen natto so I decided to try these spores that had been in the cabinet for a few months. The instructions are not in English, but can be easily found online. I used a similar process to what Emmymade on YouTube does. Of course using the spores instead of premade natto. It was a great success. To me, the natto smelled and tastes stronger than when using premade natto as a starter. The taste was great and the best natto have a tasted to date. I eat it with some jasmine rice an and sweet soy sauce. I will be using these natto spores from now on instead of using frozen natto as my starter. Quick Rundown of how I made my natto. 1. Rinsed and soaked 2 cups of soybeans for about 24 Hours. 2. Drained beans and cooked in insta pot for 25 minutes on the bean setting adding water to one inch above beans first. I let the unit depressurize on its own after the cook. 3. Sterilized a strainer, glass bowl, small measuring cup, two larger spoons, tongs and thermometer with boiling water from tea kettle. 4. Drained beans and let cool to at least 115º. Set aside about 3 tablespoons of this 'bean water' in the sterilized measuring cup 5. Put cooked beans into glass bowl that can fit in insta pot. Added about 1 of the little spoons of nattomato to beans and stirred in some of set aside water as needed. (Next time I will add the spores to this water first and then stir it in together.) There are some instructions that say you can only lay the beans three deep to have success, but mine were placed in a glass bowl that could fit inside the insta pot. The beans were several layers deep. 6. Covered bowl with saran wrap and poked many. many holes in the top. 7. Added about 1/4 cup of water to insta pot and placed steaming rack on the bottom (collapsed so bowl would fit) 8. Used Yogurt setting on Normal. Let ferment for 16 hours. I did stir the natto at 9 hours. I don't know if that was necessary. If you do this make sure your spoon is sterilized. 9. After fermentation put the beans in the fridge for 2 days and then put two portions in zip loc baggies for freezing while keeping out a several day supply in the fridge for daily consumption.

This was certainly effective at making natto. Followed a recipe carefully using the instapot. Will just need to work on seasoning to get the right tangy flavor. Definitely got the satisfying strings. Tastes very healthy. No unpleasant odor.

I am very happy with Nattomoto spores. This was my first attempt at making homemade natto, and I was nervous at every step. But after fermenting the beans and aging them for 24 hours in the fridge, tasting the finished natto brought me real joy. The package instructions are in Japanese, but the distributor’s website provides an English version. In any case, most standard natto recipes should work well with these spores. The small measuring spoon included with the spores is very useful, making dosing straightforward. I used natto beans grown in the USA, and I was very pleased with the result.

I ordered this natto starter in March and had to wait over two weeks for delivery. The package arrived on March 28, 2026, with an expiration date listed as January 2027, so it should have been perfectly fresh and active. Unfortunately, it simply does not work. I closely followed the provided instructions step-by-step. To ensure there were no environmental variables, I purchased a dedicated natto machine to maintain the exact, required temperature. Despite attempting the process three separate times, the culture failed to ferment every single time. Given the long shipping delay and the complete lack of results, I am very disappointed with this product.

I make my own Natto and this does the trick. I don't need any other methods or brands.

good starter, a tiny bit is all that is needed. it should last a long time.

Some of the bad reviews of this made me wonder, but I have had great results with these spores. I buy small soybeans labeled as “soybeans for sprouting” at Hmart, and use my Instant Pot for soaking, cooking, and fermenting my natto. First I put 2 cups of soybeans in the inner pot of my Instant Pot, add enough water to cover by several inches, and cover with the glass lid. I let them soak for about 24 hours (or until the top of the soaking water looks bubbly). Then I drain the beans into a steamer basket and put this in my pot along with a couple of cups of water. I cover this with the pressure cooker lid (remembering to close the valve) and set it to the following: Pressure Cook / High Pressure / Normal / 40 minutes and I turn off the Keep Warm function. (I have the 8 quart Instant Pot Duo, some of the buttons and settings may run a little different on other versions.) Once this is done, I let the pressure release naturally, which takes about 22 minutes. While the pressure is releasing, I fill my electric steam kettle with water and bring this to a boil. Into a large stainless steel bowl or half-gallon mason jar I throw the following items: 1/8 and 1/4 tsp , and 1 tbsp measuring spoons, steaming cloth or cheesecloth, and a spoon large enough to mix the beans. Over these I pour the boiling water to sterilize, leaving it for 5-10 minutes and then draining. Once the pressure has come down, I remove the steamer basket with my beans and place this on the counter. I pour out all but 2 tbsp of the liquid from my Instant Pot. To this I add 1 itty-bitty spoonful of the natto spores (using the little spoon included with them), 1/4 tsp brown sugar, and 1/8 tsp salt. I mix these together using the spoon I sterilized, then dump the beans in on top of this and thoroughly mix everything. I line the now empty steamer basket with a steaming cloth or cheesecloth, spoon the beans on top of this, and then fold the remaining cloth over the top to cover the beans. I give a quick rinse to the inner pot of my Instant Pot and put the steamer basket back inside. This then goes back into my Instant Pot, which I cover with a glass lid and set to Yogurt - Normal - 24 hours. I find that my natto is fully and reliably fermented at this setting after 24 hours. I then pull the steamer basket out of the pot and set in on the counter until the beans are cool. This takes several hours. Then into the fridge they go. They seem ready to eat the next morning, although traditional recipes say to let them cure in the fridge for 3-5 days before eating. I’m honestly not sure what difference it makes. How long do they keep once refrigerated? I’ve never had them go bad, although I suppose that’s possible. Some people say they become gritty or grainy if you keep them too long, although I haven’t seen that. I aim to eat these daily, but sometimes I forget about them and they sit in the fridge. They don’t seem to change much over time once fermented. To eat, I take about 1/2 cup and mix in a spoonful or two of soy sauce.