Research Trend in Traditional Fermented Foods Focused on Health Functional Evaluation

This study aimed to investigate the trends in five fermented foods used as seasonings in Korean cuisine: ganjang (Korean fermented soy sauce), doenjang (Korean fermented soybean paste), kochujang (Korean fermented red pepper paste), cheonggukjang (Korean fermented soybean product), and jeotgal (Korean salted fish). There were 634 articles on traditional fermented foods published from 1995 to 2017. Among these, 159 papers were on the health function of fermented foods, 17 on ganjang, 60 on doenjang, 20 on kochujang, 58 on cheonggukjang, and four on jeotgal. Regarding ganjang and jeotgal, seven and two articles were published, respectively, based on cell and animal experiments, but no human trials were reported. Most studies on ganjang were related to immunological activity and inhibition of inflammation. In the experiments on doenjang, 31 papers were published, including three human trials, and most were anti-obesity/anti-diabetes studies. Four epidemiological studies have been reported on soybean including soybean products as well as fermented food categories reporting effects on gastric cancer, cardiovascular disease, and atopic dermatitis. For kochujang, 12 studies including cell and animal experiments, as well as three human trials were reported. The most published topics on kochujang were anti-obesity/anti-diabetes. In addition, suppressive effects on cancer cells, increased immune activity, and inhibition of inflammation were observed. Study of cheonggukjang consisted of 47 articles, including eight human trials, and 21 of them were anti-obesity/anti-diabetes experiments. Studies related to bone mineralization, skin improvement, and immune-boosting were conducted using cheonggukjang. This review focuses on the reported health benefits of Korean fermented foods, suggesting directions to be taken while planning a study on fermented foods by generating a database for the evaluation of the health benefits of Korean fermented foods.