Nattō in the context of "Allium fistulosum"

Probiotics are live microorganisms in that are intended to support or improve the health and wellbeing of a host organism. They are commonly used in both humans and animals. Although the term refers to the microorganisms themselves, probiotics can be consumed through a range of products including yogurt, cheese, certain fermented foods (such as nattō), as well as capsules containing a single strain or a defined mixture of strains.

Probiotics are regarded as generally recognised as safe (GRAS) by the U.S. Food and Drug Administration (FDA), which supports their safety when used as intended, although this designation does not establish their effectiveness or specific health benefits. Many claimed health benefits, such as treating eczema or curing vaginal infections, lack substantial scientific support.

The soybean, soy bean, or soya bean (Glycine max) is a species of legume native to East Asia, widely grown for its edible bean. Soy is a staple crop, the world's most grown legume, and an important animal feed.

Soy is a key source of food, useful both for its protein and oil content. Soybean oil is widely used in cooking, as well as in industry. Traditional unfermented food uses of soybeans include edamame, as well as soy milk, from which tofu and tofu skin are made. Fermented soy foods include soy sauce, fermented bean paste, nattō, and tempeh. Fat-free (defatted) soybean meal is a significant and cheap source of protein for animal feeds and many packaged meals. For example, soybean products, such as textured vegetable protein (TVP), are ingredients in many meat and dairy substitutes. Soy based foods are traditionally associated with East Asian cuisines, and still constitute a major part of East Asian diets, but processed soy products are increasingly used in Western cuisines.

Branched-chain fatty acids (BCFA) are usually saturated fatty acids with one or more methyl branches on the carbon chain. BCFAs are most often found in bacteria, but can be found in nattō, dairy, vernix caseosa of human infants and California sea lions where they may play a role in fostering the development of their intestinal microbiota. Another waxy animal material containing BCFAs is lanolin.

Branched chain fatty acids are considered to be responsible for the smell of mutton and higher content causes consumers to dislike the smell of lamb meat.Branched-chain fatty acids are synthesized by the branch-chain fatty acid synthesizing system.