The purpose of this study was to determine the effectiveness of yuzu peels for preventing nonalcoholic fatty liver disease. We investigated the effect of yuzu (Citrus junos) peel extract (YPE) on fatty liver steatosis induced by a high-sucrose diet in rats. Rats fed a high-sucrose diet supplemented with 2% (w/w) YPE showed suppression of fat accumulation in the liver, compared with rats fed a high-sucrose diet alone. The functional components of YPE were analyzed by GC-MS/MS. Rats were then fed a high-sucrose diet supplemented with candidate substances detected in the YPE. Among the substances tested, myo-inositol was determined to be one of the functional components. Metabolomic analyses were performed to clarify the mechanism of action of myo-inositol in the suppression of fat accumulation in the liver. The levels of two fatty acids, myristate and oleate, were found to increase following the intake of a high-sucrose diet, but their levels were significantly decreased following the intake of a high-sucrose diet supplemented with myo-inositol. The results suggest that the functional component of YPE is myo-inositol. Additionally, myo-inositol suppressed the biosynthesis of fatty acids enhanced by the high-sucrose diet.

Chlorophyll is rapidly changed to pheophytin in acidic conditions. Therefore, lactic acid fermented green vegetables such as Brassica Rapa L. (nozawana) change to brownish yellow. Certain strains of lactic acid bacteria are able to elevate extracellular pH by producing γ-aminobutyric acid (GABA) from glutamic acid. This study was performed to evaluate the effect of GABA-producing lactic acid bacteria on the color of lactic acid fermented nozawana (nozawana-zuke). Lactobacillus buchneri LB130 was selected based on the GABA productivity in nozawana juice medium. Nozawana was fermented by an LB130 strain with or without monosodium glutamate (MSG). The degradation rate of chlorophyll in the nozawana-zuke fermented with MSG was lower than that fermented without MSG. Consequently, the green color of the nozawana-zuke fermented with MSG was retained. In addition, the nozawana-zuke fermented with MSG contained sufficient amounts of GABA (307mg/100g).

We investigated the changes in the components of juices during the pressing process of ‘Muscat Bailey A’ using a traditional method from the Champagne region of France. In the pressing of early harvested grapes for the production of sparkling wine, the tartaric acid and citric acid contents remained constant, but the malic acid content increased significantly as the pressing progressed. It was clarified that the tendency of the acidity to increase in the latter stage of pressing was the opposite of the tendency of European grapes, and was similar to the ‘Koshu’ Japanese original species. In addition, the same tendency as the early harvested grapes was observed in the study using ripe grapes for the production of still wine. In each of the pressing tests, it was confirmed that juice from the second pressing (Taille) had a higher acidity than that from the first pressing (Cuvée). It was considered that this was due to the remarkable increase of the malic acid content in the latter stage of the grape-pressing process. From the above, it was considered that when blending wine from the Cuvée and Taille, consideration must be given to the blending ratio in domestic sparkling wine-making.

Soybeans are one of the most widely cultivated and important plant resources in the world. Because of their particularly high protein content, at about 40%, they have been called “the meat of the field.” Soy protein contains all 20 amino acids humans need, and also is rich in 9 essential amino acids. Soybeans also contain various nutritional functional components, not only proteins, such as oligosaccharides, isoflavones, saponins, sterols, and tocopherols. Some soybean genetic resources possess several of these nutritional functional components. Understanding and actively utilizing their genetic mutations could help create soybeans with better nutritional characteristics. Dr. Tetsuya Yamada of the Hokkaido University Research Faculty of Agriculture described progress in the understanding of the molecular control mechanisms of genetic mutations in soybean nutritional functional components in a presentation to the research subcommittee at the 66th annual meeting of the Japanese Society for Food Science and Technology in 2019. Dr. Yamada discussed the current state and future prospects of breeding modifications for improving nutritional functional components.

Soybean seeds contain high-quality proteins that are used as a source of food, and also abundant lipids that are used as a vegetable oil. Many functional ingredients are also included in soybean seeds. We have identified qualitative and/or quantitative genetic variations in several components, such as protein, α-tocopherol, chlorophyll, and isoflavone, among soybean genetic resources. These genetic variations are available to improve the processing properties and to add some values for soy foods. We also demonstrated that a high and low temperature during seed filling enhanced the biosynthetic pathways of α-tocopherol and isoflavone, respectively. These suggest that it is possible to increase the amounts of functional components, such as α-tocopherol and isoflavones, by improving the cultivation environment of soybean in addition to the development of new soybean varieties by using genetic variations. The successful use of genetic variations and physiological properties related to soybean quality will not only enable differentiation from conventional soy products, but also create new uses for soybean.