Insights & Discussion
Natto and Miso, Japanese fermented soy foods, contain health-promoting bioactive components, including nattokinase, bacillopeptidase F, vitamin K2, dipicolinic acid, γ-polyglutamic acid, isoflavones, and phenolic acids.
The process of preparing natto involves fermenting cooked soybeans with Bacillus subtilis natto. This gives the soybeans a sticky appearance, a slippery texture, a sour aroma and a nutty flavour, and results in the production of bioactive components such as nattokinase, bacillopeptidase F, vitamin K2, dipicolinic acid, and γ-polyglutamic acid. Miso, on the other hand, refers to a paste produced by fermenting cooked soybeans with koji, which is steamed rice inoculated with Aspergillus oryzae.
The health benefits of these bioactive components, produced during the fermentation process of both natto and miso, have been identified and accentuated. These components add value to traditional soy foods, boosting their potential in promoting health. The wealth of bioactive nutrients in these foods indicate the reiterate the importance of traditional fermented foods in dietary practices.
Discover Related Insights
Long-term intake of traditionally made Doenjang, particularly high in certain species, may improve symptoms of estrogen deficiency more effectively than unfermented soybeans.
2023 Foods Improvement of Estrogen Deficiency Symptoms by the Intake of Long-Term Fermented Soybeans (Doenjang) Rich in Bacillus Species through Modulating Gut Microbiota in Estrogen-Deficient Rats Zhang T, Yue Y, Jeong SJ, Ryu MS, Wu X, Yang HJ, et al.
Animal Study Bacillus Gut Microbiota Menopause
The study involved using four different types of traditionally made Doenjang (TMD), distinguished based on the quantities of certain species and biogenic amines they contained. These were used to observe possible alterations in energy, glucose, and lipid metabolism in estrogen-deficient female rats via potential modification of the gut microbiota. This involved comparing a control group of rats that underwent ovary removal with five other groups that were supplemented with different types of TMD and cooked soybeans.
The outcomes revealed that weight gain and visceral fat mass were lower and lean body mass was higher in the TMD and cooked soybean intake groups compared to the control group, however, these figures were not as good as those in the normal control group. Additionally, the hepatic triglyceride content was lower with TMD intake. It was further observed that the intestinal health significantly improved in the TMD groups, and some groups revealed more improvements than others. Concerning gut microbiota, certain groups showed an increase in certain types of organisms, suggesting a benefit from high amounts of the specific species in TMD. The study inferred that TMD rich in certain species correlates positively with the regulation of estrogen-related markers.