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What Is Natto? Ask Paul

Slippery, savory natto is having a social media moment. About time!
By Published Mar. 15, 2023

You either love or hate this traditional Japanese food. What's the fuss about?

What Is Natto?

Natto is a traditional treat from Japan, consisting of briefly fermented soybeans coated in a stringy, sticky goo. Like soy sauce and miso, it develops complex savory flavor through the action of beneficial microbes.

Unlike soy sauce and miso, which are widely accepted outside Japan, natto hasn’t caught on globally in the same way. 

What Does Natto Taste Like?

Natto has been slow to catch on because it has a strong flavor that’s not always easily appreciated: malty, cheesy, sweaty, bitter, and sometimes ammoniacal, like a washed-rind cheese. But more than that, the characteristic that has made it famous on social media is the long, slippery strings of goo that develop in natto during fermentation.

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Why Is Natto Stringy?

A species of bacteria called Bacillus subtilis, also known as nattokin, is responsible for turning steamed soybeans into natto. During just 18 hours or so at around 100°F, the bacteria break down the beans’ protein into savory amino acids and its fat into buttery, cheesy flavor compounds. They also produce long, gooey chains of polysaccharides (like those in okra) and polypeptides.

In the eyes of natto appreciators, this goo is the point. According to a 2001 Journal of Food Science article, “[S]ilky stickiness feeling due to a high viscosity of the mucilage is the most important criterion of a good natto.” The Japanese term for this texture is “neba-neba”.

Stirring natto before eating it helps the mucilage strands stretch and link up: The more you mix, the more strings of goo you get.

How to Enjoy Natto

The classic way of eating natto is simple: natto over rice, dressed with soy-based sauce, scallion, and/or a little mustard. That simplicity allows the flavor—and texture—to shine. But for natto novices who want to start with a less natto-forward preparation, it’s awfully good mixed into scrambled eggs: Stir a 2-ounce packet of natto into three beaten eggs with a pinch of salt and then fry and top with chopped scallion.

Once you get to know natto, it becomes extremely craveable. The Western culinary aesthetic has an endless appetite for long strings of stretchy cheese, so why not natto? Anyone for natto nachos?

Where to Buy Natto

Natto can be bought refrigerated or frozen at Japanese food markets and is also easily found online.

How to Make Your Own Natto

Store-bought natto typically comes frozen in little polystyrene boxes containing individual servings, often with a plastic packet of optional sauce. If you’re curious, or eat a lot of natto and get tired of tossing out all the packaging, it’s very easy to make your own in a multicooker.

  • Cook 1 pound dry soybeans in pressure cooker mode until tender.
  • Drain and allow to cool to 100°F or less.
  • With a clean spoon, mix in one packet of store-bought natto or powdered natto starter culture.
  • Close the pot and set it to 100°F for 24 hours.
  • After 24 hours, refrigerate the natto for another 24 hours.
  • Enjoy.


Advanced fermenters may want to use a home-built fermentation chamber for this and all sorts of other projects.

Ask Paul Adams, senior science research editor, about culinary ambiguities, terms of art, and useful distinctions: paul@americastestkitchen.com

Photo: Nattō (aka rotten soybeans) by JD is licensed under CC BY 2.0, modified by Rose Flynn

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JC
JOHN C.
16 days

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too. I've done this using a rimmed sheet pan instead of a skillet and put veggies and potatoes around the chicken for a one-pan meal. Broccoli gets nicely browned and yummy!

Absolutely the best chicken ever, even the breast meat was moist! It's the only way I'll cook a whole chicken again. Simple, easy, quick, no mess - perfect every time. I've used both stainless steel and cast iron pans. great and easy technique for “roasted” chicken. I will say there were no pan juices, just fat in the skillet. Will add to the recipe rotation. Good for family and company dinners too.

MD
MILES D.
JOHN C.
9 days

Amazed this recipe works out as well as it does. Would not have thought that the amount of time under the broiler would have produced a very juicy and favorable chicken with a very crispy crust. Used my 12" Lodge Cast Iron skillet (which can withstand 1000 degree temps to respond to those who wondered if it would work) and it turned out great. A "make again" as my family rates things. This is a great recipe, and I will definitely make it again. My butcher gladly butterflied the chicken for me, therefore I found it to be a fast and easy prep. I used my cast iron skillet- marvellous!

CM
CHARLES M.
11 days

John, wasn't it just amazing chicken? So much better than your typical oven baked chicken and on par if not better than gas or even charcoal grilled. It gets that smokey charcoal tasted and overnight koshering definitely helps, something I do when time permits. First-time I've pierced a whole chicken minus the times I make jerk chicken on the grill. Yup, the cast iron was not an issue.