Soybean Koji Research Articles

Plant-based polyphenol rich protein supplementation attenuated skeletal muscle loss and lowered the LDL level via gut microbiota remodeling in Taiwan's community-dwelling elderly.

Sarcopenia, characterized by muscle loss, negatively affects the elderly's physical activity and survival. Enhancing protein and polyphenol intake, possibly through the supplementation of fermented black soybean koji product (BSKP), may alleviate sarcopenia by addressing anabolic deficiencies and gut microbiota dysbiosis because of high contents of polyphenols and protein in BSKP. This study aimed to examine the effects of long-term supplementation with BSKP on mitigating sarcopenia in the elderly and the underlying mechanisms. BSKP was given to 46 participants over 65 years old with early sarcopenia daily for 10 weeks. The participants' physical condition, serum biochemistry, inflammatory cytokines, antioxidant activities, microbiota composition, and metabolites in feces were evaluated both before and after the intervention period. BSKP supplementation significantly increased the appendicular skeletal muscle mass index and decreased the low-density lipoprotein level. BSKP did not significantly alter the levels of inflammatory factors, but significantly increased the activity of antioxidant enzymes. BSKP changed the beta diversity of gut microbiota and enhanced the relative abundance of Ruminococcaceae_UCG_013, Lactobacillus_murinus, Algibacter, Bacillus, Gordonibacter, Porphyromonas, and Prevotella_6. Moreover, BSKP decreased the abundance of Akkermansia and increased the fecal levels of butyric acid. Positive correlations were observed between the relative abundance of BSKP-enriched bacteria and the levels of serum antioxidant enzymes and fecal short chain fatty acids (SCFAs), and Gordonibacter correlated negatively with serum low-density lipoprotein. In summary, BSKP attenuated age-related sarcopenia by inducing antioxidant enzymes and SCFAs via gut microbiota regulation. Therefore, BSKP holds potential as a high-quality nutrient source for Taiwan's elderly, especially in conditions such as sarcopenia.

Changes in volatile aroma profiles of soybean, rice, and wheatkojiduring fermentation using stir bar sorptive extraction followed by gas chromatography‐mass spectrometry and descriptive sensory analysis

AbstractDoenjang, a fermented soybean paste, is a traditional food ingredient in Korea. While the flavor ofdoenjangis heavily dependent onkoji, studies on the aroma characteristics ofkojiremain limited. This study aimed to determine the changes in the aroma profiles of soybeankoji(SBK), ricekoji(RK), and wheatkoji(WK). Aroma analysis was performed using stir bar sorptive extraction followed by gas chromatography‐mass spectrometry (GC‐MS) and descriptive sensory analysis. In SBK, bean‐associated aroma was strongly developed due to the lipid‐derived compounds, whereas in RK, sweet aromas were relatively strong at 72 h due to the sweet‐smelling ester compounds. In WK, the nutty cracker attribute was significantly strengthened during fermentation due to the high concentration of aldehydes. The results showed that the aroma profile ofkojiwas influenced by main ingredient, and this finding is useful in improving aroma development with the use ofkojiin the fermented food industry.Practical ApplicationKojiis one of the key ingredients utilized in commercializeddoenjangmaking process in Korea, in order to accelerate the fermentation process. In this study, influences of raw materials ofkojiin the aroma development ofdoenjangwere investigated using descriptive sensory analysis and instrumental flavor analysis using GC‐MS. Raw material‐driven aroma compounds were documented in differentkojisamples, in which influences the aroma characteristics ofdoenjangmade withkojimade with different raw materials. Finding from this study can aiddoenjangmanufacturers for versatile aroma development of commercializeddoenjang.

Flavor differences of soybean and defatted soybean fermented soy sauce and its correlation with the enzyme profiles of the kojis.

Soybeans and defatted soybeans, commonly used as protein ingredients, have different flavors of their fermented soy sauce. Clarifying the differences between the two soy sauces, as well as the formation mechanism, is an important prerequisite for improving the flavor of defatted soybean soy sauce. To this goal, the aroma characteristics of two soy sauces and their volatile profiles were compared by sensory evaluation and gas chromatography-mass spectrometry, and eight enzyme activities and volatile profiles of matured koji were determined. Sensory results showed that the acids, fruity and cooked potato-like attributes were higher in whole soybean fermented soy sauce, whereas defatted soybean soy sauce exhibited higher smoky and malty attributes, closely related to the contents of aroma-active compounds in soy sauce, such as isobutyl acetate, 2/3-methylbutanal, acetic acid and 2/3-methylbutanoic acid. The content of most volatiles in the matured kojis showed a consistent trend with that of soy sauce: alcohols, acids, furan(one)s and ketones. Interestingly, acid protease and cellulase activities were 3.3 and 1.6 times higher in the whole soybean koji than in defatted soybean koji, respectively, whereas neutral protease, aminopeptidase, glucoamylase and β-glucosidase were approximately 2.0 times higher in defatted soybean koji. In summary, the flavor differences between soybean and defatted soybean fermented soy sauce were not only caused by the differences in the content of flavor precursors in the materials, but also closely related to the differences in the enzymatic profiles accumulated during the koji-making process. © 2022 Society of Chemical Industry.

Predictive Model for Oral Status in Elderly People in a Taiwanese Nursing Home Using a High-Protein Black Soybean Koji Food.

With increased age, the appetite, chewing, swallowing, and digestive ability gradually decrease. Previous studies have shown that poor oral health is associated with an inadequate intake of macro and micronutrients and malnutrition. Therefore, improving the diet of elderly people and promoting nutrient absorption will help to improve the quality of life for elderly people. However, few studies have predicted their oral ability based on different food textures and other factors. The purpose of this study was to explore the correlation between oral assessment and texture parameters of high-protein black soybean koji products in elderly people in a nursing home. We used cross-sectional study design for seventy-nine residents aged 65 years and older were recruited. Three different texture of cookies, including normal cookie hardness (1.4 × 105 N/m2), minced cookie hardness (4.4 × 104 N/m2), and pureed cookie hardness (1.4 × 104 N/m2) were provided to participants to test the oral status. An oral assessment scale was used by a dentist to evaluate the oral status of the elderly participants. Different cookie textures showed a significant positive correlation with pronunciation (r = 0.237, p < 0.05), face (r = 0.371, p < 0.01), tongue (r = 0.362, p < 0.01), pharynx (r = 0.256, p < 0.05), swallowing (r = 0.272, p < 0.05), breathing (r = 0.315, p < 0.01), and the total oral score (r = 0.339, p < 0.01). We also used the high-protein black soybean koji products combined with elderly people’s comprehensions in a predictive model that had a moderately high correlation to predict the oral status in the elderly group (r = 0.612). We concluded that the high-protein black soybean koji product was associated with the oral ability of elderly people in a nursing home in Taiwan. Our findings indicated that elderly people could immediately understand the correct food texture.

Liberation of eicosapentaenoic acid and degradation of the major cell wall polysaccharide porphyran by fermentation of nori, the dried thalli of Pyropia yezoensis, with koji

In this study, dried sheets of nori, shredded and processed thalli of the red alga Pyropia yezoensis, were fermented with either barley, rice or soybean koji. High-performance liquid chromatographic analyses of the lipid extracts of the fermented products indicated that the fermentation of nori with all kinds of tested koji released free fatty acids, including the eicosapentaenoic acid, from ester lipids. We found that approximately half of the eicosapentaenoic acid in nori had been released as the free fatty acid at up to 4 weeks of fermentation at 30 °C and more than 65% at 8 to12 weeks in the fermented products with barley and rice koji. We also demonstrated the degradation of porphyran, a major cell wall polysaccharide of nori, by gel chromatography on Sephacryl S-300 HR of hot water extracts of the fermented products of nori with barley koji. Approximately two-third of porphyran had been degraded to porphyran oligosaccharides up to 6 weeks of fermentation. Fermentation of nori with koji may bring out the potential health-promoting functions of nori.

Effect of Soybean and Soybean Koji on Obesity and Dyslipidemia in Rats Fed a High-Fat Diet: A Comparative Study

Soybean koji refers to steamed soybeans inoculated with microbial species. Soybean fermentation improves the health benefits of soybeans. Obesity is a serious health concern owing to its increasing incidence rate and high association with other metabolic diseases. Therefore, we investigated the effects of soybean and soybean koji on high-fat diet-induced obesity in rats. Five-week-old male Sprague-Dawley rats were randomly divided into four groups (n = 8/group) as follows: (1) regular diet (RD), (2) high-fat diet (HFD), (3) HFD + steamed soybean (HFD+SS), and (4) HFD + soybean koji (HFD+SK). SK contained more free amino acids and unsaturated fatty acids than SS. In a rat model of obesity, SK consumption significantly alleviated the increase in weight of white adipose tissue and mRNA expression of lipogenic genes, whereas SS consumption did not. Both SS and SK reduced serum triglyceride, total cholesterol, and low-density lipoprotein cholesterol levels, and increased high-density lipoprotein cholesterol levels. SS and SK also inhibited lipid accumulation in the liver and white adipose tissue and reduced adipocyte size. Although both SS and SK could alleviate HFD-induced dyslipidemia, SK has better anti-obesity effects than SS by regulating lipogenesis. Overall, SK is an excellent functional food that may prevent obesity.

Influences of salt and koji contents on chemical properties of fish sauce from tilapia frames

Influences of salt (5%–20% w/w of digested material) and soybean koji (3%–10% w/w of digested material) on chemical properties of fish sauce from tilapia frame after 4 months’ fermentation using response surface methodology was studied. Results found that the salt content showed quadratic effect on ammonia nitrogen and amino nitrogen while linear effect on formaldehyde nitrogen and NaCl contents of samples were observed (P < 0.05). Estimation response surfaces revealed that the formaldehyde nitrogen, ammonia nitrogen and amino nitrogen contents decreased while NaCl content increased as salt content increased. For the effect of koji, the significant effect of koji content on non-enzymatic browning value of fish sauce samples in linear manner was observed (P < 0.05). The non-enzymatic browning value of sample increased as koji content increased. The both of salt and koji contents showed the linear effect on total acidity value while two-factor interaction terms on total nitrogen of sample was found (P < 0.05). For the consumer acceptability testing, an acceptance score of the incubated fish sauce sample with a values of 6.50–7.43 (like slightly to like moderately) was obtained. The results showed that it is possible to make a good quality fish sauce from tilapia frame by-product.

New sauces produced by koji fermentation of kamaboko show acceptable sensory characteristics, improved antioxidant activities, and high angiotensin-converting enzyme inhibition

In our previous study, kamaboko was fermented in koji to prolong its shelf life and to increase its health-promoting effects. After fermentation, the texture of the kamaboko became cheese- or tofuyo-like. In the present study, sauces were produced by the fermentation of kamaboko in fermentation beds of wheat (WS), rice (RS), brown rice (BS), or soybean koji (SS), and their sensory qualities examined. WS, RS and BS had similar qualities to commercial oyster sauce. Fried cabbage with RS had significantly better overall acceptance than fried cabbage with oyster sauce. SS had significantly higher ash, protein and fat contents, and significantly lower carbohydrate contents than WS, RS, and BS. Free amino acid contents increased following fermentation for all sauces, and were highest in SS. The sugar contents of WS, RS, and BS were significantly higher than that of SS. SS had the highest phenolic content followed by BS, WS and RS. Antioxidant activity and angiotensin-converting enzyme (ACE) inhibition were highest in SS. All the new sauces had significantly higher free amino acid contents than the equivalent fermentation beds without kamaboko.

Physiochemical Quality and Sensory Characteristics of koji Made with Soybean, Rice, and Wheat for Commercial doenjang Production.

The purpose of this study was to compare the physiochemical quality characteristics and sensory profiles of three types of koji: soybean, rice, and wheat koji. Koji is made by inoculating Aspergillus oryzae following the standard method of manufacturing. The physiochemical characteristic and sensory profiles were performed after fermenting samples of koji for a 72 h period. The physiochemical quality characteristics that were tested include pH, moisture content, color, acidity, TA, amino-type nitrogen content, reducing- and total-sugar content, and alcohol content; the enzymatic activities that were tested include amylase (α- and β-) and protease (neutral and acidic) activities. A descriptive sensory analysis was conducted on three types of koji with a highly trained sensory panel (n = 7) using the SpectrumTM Method. Differences in physiochemical and sensory profiles were observed on three koji samples (p < 0.05). Soybean koji had higher values in acid and TA, while rice koji had the highest values in reducing and total sugar, at 90.3 mg/g and 107.5 mg/g respectively. Wheat koji had the lowest values in protease activities. The flavor profile of soybean koji was characterized by bean sprout, cracker, and cheonggukjang aromatics; that of rice koji was characterized by overripe banana, solvent, syrup, and parboiled rice aromatics; and that of wheat koji was characterized by woody and roasted aromatics.

Cultivation temperature and length affect the antioxidant activity and total phenolic content of soybean Koji prepared with Aspergillus awamori

In this study, soybean koji was first fermented with Aspergillus awamori, a starter organism commonly used for the fermentation of sake, at 25, 30 or 35°C for a period of 1-5 days. Antioxidant activity, including DPPH radical-scavenging effect and Fe2+-chelating ability, and total phenolic content of the methanol extract of these fermented soybean koji as well as mycelial propagation of starter organism were compared. Results revealed that fermented for a same period of 3 days, the DPPH radical-scavenging effect exerted by the 30°C-koji extract was the highest showing 2.5-3.5 folds of that fermented at 25 or 35°C. The Fe2+-chelating ability exerted by the 30°C-koji extract was also found to be 3.6-3.8 times higher than those fermented at other temperatures. Furthermore, it was also noted that increasing or decreasing cultivation time from 3 days resulted in a decreased antioxidant activity of the koji extract. Cultivation temperature and length were also observed to affect the mycelial propagation and the total phenolic content of the koji extract. Maximum mycelial propagation of A. awamori was achieved after cultivation at 30°C for 3 days. Finally, the highest phenolic content noted in 30°C-koji extract was closely correlated to the highest antioxidant activity observed.

Compositional differences, antioxidant activity, angiotensin-converting enzyme inhibition, and sensory characteristics of kamaboko fermented in wheat, rice, brown rice, and soybean koji

Fermentation of kamaboko in koji with wheat (KW), rice (KR), brown rice (KB), or soybean (KS) was performed by simulation of tofuyo processing. Moisture and protein content decreased with fermentation, while other detected compounds increased significantly. Ash content increased from 12.9 g/100 g in kamaboko to 17.9–20.2 g/100 g (KW, KR, and KB) and 26.8 g/100 g (KS) after 4 weeks of fermentation. Mineral and fatty acid composition varied. After 8 weeks of fermentation, KW, KR, and KB exhibited total free amino acids, sugar, and phenolic content of 2804–3396 mg/100 g, 43.5–55.3 g/100 g, and 207–263 mg/100 g, while KS showed 12,300 mg/100 g, 11.3 g/100 g, and 539 mg/100 g, respectively. Radical scavenging and angiotensin-converting enzyme (ACE) inhibitory activity increased significantly following fermentation. KS showed the strongest 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity and ACE inhibition. Sensory analysis revealed that KW, KR, and KB were significantly more favorable than KS, with significantly stronger sweetness and weaker smell, saltiness, and aftertaste. These results indicate that wheat, rice, and brown rice koji-fermented products are acceptable as food, and that the soybean koji-fermented product is a useful source of bioactive compounds such as peptides and phenolics.

Effects of Soybean koji Prepared with Aspergillus oryzae on the Improvement of the Nails of in their 40s to 60s Women

Effects of Soybean koji Prepared with Aspergillus oryzae on the Improvement of the Nails of in their 40s to 60s Women

Analysis of the cooked aroma and odorants that contribute to umami aftertaste of soy miso (Japanese soybean paste)

Soy miso, the traditional Japanese fermented soybean paste prepared using soybean koji, is used for imparting umami aftertaste to cooked dishes. The objective of this study was to identify the key odorants of cooked soy miso and their influence on umami aftertaste perception. Volatile compounds of soy miso and two rice misos were prepared using simultaneous distillation-extraction, and the key odorants were identified by using the gas chromatography-olfactometry/aroma extract dilution assay approach, and soy miso was compared with rice misos. Forty-one aroma-active compounds were detected in cooked soy miso, and malty, green, roasty and sulfury aromas were identified as the characteristic aromas. Finally, sensory evaluation was conducted to assess the contribution to the umami aftertaste of six key compounds with the highest flavour dilution factor. Results revealed that dimethyl trisulfide, which was newly identified in cooked miso, contributes to the umami aftertaste and palatability of cooked soy miso.

Metabolomics reveal that amino acids are the main contributors to antioxidant activity in wheat and rice gochujangs (Korean fermented red pepper paste)

Metabolite profiling of gochujangs (Korean fermented red pepper paste) produced from different kinds of raw materials (WG, wheat gochujang; RG, rice gochujang) was performed using gas chromatography time-of-flight mass spectrometry (GC–TOF-MS) and ultra-performance liquid chromatography quadrupole time of flight mass spectrometry (UPLC-Q-TOF-MS). Using principal component analysis (PCA), gochujang samples were differentiated based on the differences in starchy source and secondary materials used in their production. The content of amino acids and sugars was higher in WG, whereas the content of flavonoids, soyasaponins, and γ-aminobutyric acid (GABA) was higher in RG. The content of flavonoids and soyasaponins was related to the higher soybean koji content of RG. The level of antioxidant activity in WG was higher than that in RG and showed a strong positive correlation with amino acid content and a negative correlation with flavonoid content. Although the Trolox equivalent antioxidant capacity of flavonoids was only 10-fold higher than that of amino acids in an antioxidant activity assay, the total amino acid content was as much as several hundred fold higher than total flavonoid content in gochujang. This result suggests that the amino acids could be a main contributor to the antioxidant capacity in gochujang.

세계적 소스류의 품질특성 다양화를 이용한 고추장소스개발

Gochujang, a kind of fermented red pepper paste with soybean koji, is a traditionally using spices in Korea and is characterized by its special taste in combination with hot, sweet and salty taste, and its component are consist of protein, carbohydrates, capsanthin and capsinoids, vitamin and other minor components. We tried to develop Gochujang sauce characterized by mild hot and spicy taste, proper viscosity and its strong application to steak, fried food, pizza and others. Gochujang sauce tended to show strong red color and lightness as pH decreases and Paprica oleoresin improved a value to 12.11 and L value to 24.24 which is similar to tomato paste 1:1-1.5:1 ratio of Gochujang and tomato paste was evaluated to be acceptable in the aspect of Gochujang's characteristics.

콩 코오지를 이용한 된장의 품질 특성

This study investigated the quality characteristics and sensory evaluation of Doenjang samples made of soybean koji and prepared with Bacillus subtillus 3-B-1 and/or Aspergillus oryzae 6-M-1 isolated from traditional Meju, to replace the koji with wheat flour. Among the quality characteristics of doenjang during its fermentation at 30°C for 40 days, its moisture decreased by degrees, but its amino-type nitrogen and reducing sugar increased by degrees. The color of the doenjang made of koji and prepared with Aspergillus oryzae 6-M-1 changed more significantly than that of the doenjang with Bacillus subtilis 3-B-1. The viable cell and mold counts increased by degrees during the fermentation. The results of the sensory evaluation of the doenjang made with koji and prepared with Aspergillus oryzae 6-M-1 did not significantly differ from those of the doenjang with Bacillus subtilis 3-B-1 and of the commercial doenjang. These results showed the possibility of preparing doenjang with soybean koji instead of wheat flour koji.

Effect of black soybean koji extract on glucose utilization and adipocyte differentiation in 3T3-L1 cells.

Adipocyte differentiation and the extent of subsequent fat accumulation are closely related to the occurrence and progression of diseases such as insulin resistance and obesity. Black soybean koji (BSK) is produced by the fermentation of black soybean with Aspergilllus awamori. Previous study indicated that BSK extract has antioxidative and multifunctional bioactivities, however, the role of BSK in the regulation of energy metabolism is still unclear. We aimed to investigate the effect of glucose utilization on insulin-resistant 3T3-L1 preadipocytes and adipogenesis-related protein expression in differentiated adipocytes with BSK treatment. Cytoxicity assay revealed that BSK did not adversely affect cell viability at levels up to 200 μg/mL. The potential for glucose utilization was increased by increased glucose transporter 1 (GLUT1), GLUT4 and protein kinase B (AKT) protein expression in insulin-resistant 3T3-L1 cells in response to BSK treatment. Simultaneously, BSK inhibited lipid droplet accumulation in differentiated 3T3-L1 cells. The inhibitory effect of adipogenesis was associated with downregulated peroxisome proliferator-activated receptor γ (PPARγ) level and upregulated Acrp30 protein expression. Our results suggest that BSK extract could improve glucose uptake by modulating GLUT1 and GLUT4 expression in a 3T3-L1 insulin-resistance cell model. In addition, BSK suppressed differentiation and lipid accumulation in mature 3T3-L1 adipocytes, which may suggest its potential for food supplementation to prevent obesity and related metabolic abnormalities.

비지 koji 첨가에 따른 양조간장의 발효 중 이화학적 특성 평가

To evaluate the practical use of okara koji in soy sauce fermented with soybean koji, the okara koji was fortified with different contents (0, 50, and 100%) in soybean koji and then fermented for 90 days. The saltiness of the soy sauce was about 17.15~17.22%. The higher okara koji content showed lower net soluble solid contents of 8.73, 6.12, and 2.50%, as well as lower acidity levels of 1.09, 0.98, and 0.47%. The buffering capacity of the soy sauce decreased to 1.26-3.41 by adding higher okara koji. The protease activity was higher in the soy sauce with 50% orara koji and decreased with longer fermentation. Also, the tyrosine content peaked to 275.2 mg% after 90 days. -amylase showed higher activity in the soy sauces fortified with okara koji, which resulted in the highest total sugar and reducing sugar contents after 60 days. The total sugar and the reducing sugar in the soy source decreased after longer fermentation. The total free amino acid contents of the soy sources fortified with okara koji (0, 50, and 100%) were 41.68 mg/mL, 33.10 mg/mL, and 9.27 mg/mL, respectively. In particular, the glutamic acid contents of the three types of soy sauces were highest, and most amino acids, except for glutamine, increased during the fermentation for 90 days. The sensory evaluation, except of the saltiness and color, showed similar values in the soy sauces, except in the okara koji 100%. Thus, okara koji could be a valuable ingredient of traditional soy sauces. However, the 50% okara koji did not differ significantly from the others.

Production of Enzyme and Growth of Aspergillus oryzae S.on Soybean Koji

 Abstract—Soybean koji is an important ingredient for traditional fermented food in South-East Asia and East Asia. It provides large amount of enzyme from koji mold, Aspergillus oryzae S., to digest nutrients in substrates. This study aimed at production of certain enzymes in soybean koji and potential to be applied for accelerating fish sauce fermentation. Koji containing 60% soybean was used as substrate to investigate the enzyme production by A. oryzae S. The growth of this mold was enumerated by potato dextrose agar. The mycelium development of A. oryzae S. was observed by scanning electron microscope. During koji production, pH of soybean koji increased from 6.32 to 6.07. It was caused by extracellular proteins production. The highest neutral protease, alkaline protease and amylase activities were 84.38, 41.35 and 200 unit/g of dry weight, respectively. Moreover, growing of enzyme activities on soybean koji correlated with the growth of this mold. Electron micrograph showed that spores of A. oryzae S. were formed after 48 h of cultivation period. Additionally, the highest enzymes activities were also shown in this stage.

Enzyme Production and Growth of Aspergillus oryzae S. on Soybean Koji Fermentation

Soybean koji is an important ingredient for traditional fermented food in South-East Asia and East Asia. It provides large amount of enzyme from koji mold, Aspergillus oryzae S., to digest nutrients in substrates. This study was aimed at production of certain enzymes in soybean koji and potential to be applied for accelerating fish sauce fermentation. Koji containing 60% soybean was used as substrate to investigate the enzyme production by A. oryzae S. The growth of this mold was enumerated by scanning electron microscope. During koji fermentation, pH increase of soybean koji was caused by enzymes production. The highest protease and amylase activities were 84.38 and 200 unit/g of dry weight, respectively. Moreover, growing of enzyme activities on soybean koji correlated with the growth of this mold. Electron micrograph showed that spores of A. oryzae S. were formed after 48h of cultivation period. Additionally, the highest enzymes activities were also shown in this stage.