Note from Shannon: Please welcome Sarah, CFH Customer Service Representative and Cultured Kitchen-Keeper.
Natto is purported to be one of the most healthful forms of fermented soybeans. But, soybeans are not the only legumes you can make natto from.
With just two pounds of rinsed organic, dry black beans ready for an overnight soaking, you too can get started making your own black bean natto. Here’s how.
In the morning, rinse your beans well and place them in a large pot with fresh water. Bring to a boil and cook the beans until just tender. I prefer my natto with some firmness, but if you like really soft natto, keep cooking longer. I boiled mine for about 30-40 minutes, until they were the tenderness I wanted.
While these are cooking, start another large pot of water. Bring to a boil and start adding any utensils, measuring cups or containers you will use to make your natto. If it’s going to touch the beans, boil it.
Drain the cooked beans and place in your large, boiled bowl. Stir the beans occasionally to make sure they cool evenly. You want to bring them down to 110-115° temperature range. Mix one scoop of the natto spores into 2-3 Tbsp of freshly boiled water that has also cooled. Pour over the beans and stir well to make sure the culture is evenly distributed. If your beans are particularly dry, add enough more boiled water to moisten. This is not a dry culture like Tempeh.
Yes that teeny little scoop is all the nattomoto you need to make a big batch of natto!
Now transfer your beans to shallow pans that will fit in your culturing appliance of choice. If you are using your oven, go big!. I used my small cooler, so I found some small containers that would hold my beans at a depth of 2-3 inches.
To cover your beans, either boil cheesecloth or muslin and wring out, or use unbleached parchment paper. Lay the cloth or paper over the beans, and then seal the container with a layer of foil. Place the beans in your culturing place that you have confirmed maintains a temperature of about 100°F.
A cube dehydrator works very well. Some people have an oven with a light that will maintain the correct temperature. I use a small cooler and heating pad.
A trick I have learned for making natto with lots of strings is to “heat shock” the natto. For the first 2-3 hours that your natto cultures, try to keep the temperature near 110°F. Then drop the temperature down to 100 for the remainder of the time. My batch of black bean natto took 23 hours to culture.
An important consideration, especially if you live with others, is to find an isolated place to culture your natto. It has a very strong smell while culturing! And during a 23-24 hour culturing time, you are bound to have complaints! A garage, sheltered spot outdoors or even a room with a good ventilating fan are all good options. Culturing near an open window next to a fan would also work.
As soon as your natto is forming lots of stringy gels, transfer it immediatedly to the refrigerator. After 6-8 hours, it is ready to eat.
I ate mine for breakfast with some rice noodles in spicy sauce with lettuce, green onions and a poached egg.
I have had some questions from customers about their natto not being as stringy as commercial natto. So here is a comparison. The first picture of the finished beans is just plain natto after being refrigerated for 8 hours.
This one is with some tamari stirred in. Just a little liquid makes a big difference! If you are comparing your natto to commercial natto, keep in mind the ingredients and that the commercial natto has been aged for a while before making it to your bowl.
Natto will keep for about 4-6 weeks in the refrigerator, though the smell will intensify as it ages. For a mild flavor, it is best to consume it within a week. For longer storage, you can freeze natto for several months. But you will need to consume it within 5-7 days of defrosting.