Natto spelled nattō (納豆) is a Japanese cultured soybean dish. It is made with the help of a bacterial culture, namely Bacillus subtilis var natto.
The bacteria create a stringy polymer biofilm as they ferment the beans. They also create the enzyme nattokinase, which is known as an immunity boosting and cardiovascular disease thwarting compound. (source)
In Japan, it is traditionally eaten as a breakfast food, over rice with scallions and soy sauce. However, it is quite versatile, and can be mixed anywhere where beans are called for!
You need a source of the starter which contains the bacterial culture. For finding high quality starter cultures, I like both Cultures for Health (*I am an affiliate) and GEM Cultures (not an affiliate, just a fan) based in Washington state, united States. The latter is old school (you have to email your order, then they will request payment from you… but they at least use Paypal now!) However, I did not find the included recipe from GEM cultures to be helpful or very accurate. I found better advice in other places, including Cultures for Health.
I have read that you can use mature natto to backslop future batches, at least a few times before it weakens. I have not tried this myself, but intend to and will update this post in the future with results.
Natto is definitely an acquired taste! It has a rather unpleasant aroma (smelling of ammonia), and if you’re not used to it, a stringy texture which can be off-putting. The flavor is rather neutral, however, making it ideal for such (literal) mashup dishes as “natt-tuna salad” (fish-free!) or “natt-amole” (playing the lead role instead of avocado). I have made hummus with it, too. Having all those additional flavors traditional hummus offers is a great way to mask the questionable texture and flavor of natto.
If you’re familiar with my preferences, you know that I don’t like soybeans. Fortunately, like most cultured bean ferments, natto can be made with any legume! I successfully made natto batch using chickpeas.
I rigged up a cooler as the incubation chamber here. You could also use any kind of curing chamber that can hold a steady 104°F/40°C temperature for 24 hours or so. You don’t need to actively manage humidity, as long as you keep the beans covered with plastic and a towel during the culturing.
This one time, we were on a late night live talk show in Portland, Oregon, stirring natto from Wanpaku Natto.
- incubating chamber (box with heat source) https://fermentersclub.com/curing-chamber/
- 250 grams (1/2 lb.) dried chickpeas
- 1 tsp. (5 ml) home-scale natto starter (i.e. mixed with rice flour)
- filtered water
- Soak the dried chickpeas at least 12 hours in cool filtered water (750 ml or 3 times the volume of beans).
- Drain beans, and cook in twice the volume of fresh filtered water for 45 minutes at a slow simmer. Beans should be cooked completely through.
- Drain beans, let cool down to 104°F/40°C. Optionally remove the husks. Pour beans into a shallow pan (pie dish, casserole, e.g.) where the depth of beans does not exceed 2 inches (5 cm).
- Sprinkle natto starter and mix evenly throughout beans. Ensure layer is flat and even. Add plastic wrap to cover beans and keep most of the moisture in. They do need a little oxygen, so you can leave one corner or edge of the wrap open.
- Wrap container in a dish towel and place in a spot such as an incubator that can be kept constant 104°F/40°C for 24 hours.
- Once the beans have developed a whitish splotchy layer throughout, and an ammonia-like aroma is present, the natto is finished.
- Remove from chamber. Let cool 2 hours, then place in refrigerator to "cure" for another 1 to 3 days for best flavor.
- Store in an airtight container in refrigerator for up to a few weeks. For longer shelf life, store airtight in freezer.