Four types of brewed tea are known in Japan: Awa-bancha, Goishi-cha, Ishizuchi-kurocha, and Batabata-cha in Tokushima, Kochi, Ehime, and Toyama prefectures, respectively. Some brewed teas are produced by fermentation using lactic acid bacteria that belong mainly to the genus Lactobacillus. However, in Kamigare district of Ibigawa Town, Gifu Prefecture, tea is cultivated using organic methods, although the first harvest tea shipment is limited and coarse tea leaves are discarded. Therefore, we isolated lactic acid bacteria from the same area and aimed at creating a novel brewed tea type in the Kamigare district using coarse tea leaves.

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 In this study, we evaluated the characteristics of lactic acid bacteria, namely Lactiplantibacillus pentosus and Levilactobacillus brevis, isolated from Awa-bancha. Awa-bancha is a post-fermented tea produced in the Tokushima Prefecture of Japan. We found that both L. pentosus AWA1922 and L. pentosus AWA1955 were highly resistant to artificial digestive juices and adhered to the intestinal cells, suggesting that they can be used as potential probiotics．In addition, L. brevis AWA1978, L. brevis AWA1984, and L. brevis AWA1985 not only showed high gamma-aminobutyric acid production but also grew well in tea extract. Hence, by using these lactic acid bacteria isolated from Awa-bancha, it may be possible to develop functional foods and supplements.

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 Brown rice, in comparison with white rice possesses higher nutritional qualities and functional properties but have lower sensory quality. To examine the potential of using superheated steam (SHS) to improve the overall eating quality of brown rice, microbial, physical, sensory and functional characteristics of SHS-treated brown rice was compared to raw, untreated brown rice. Microbiological analysis confirmed that the SHS pre-treatment effectively sterilized the brown rice removing all insects and fungi. Although, majority of the physical and sensory characteristics were not significantly different, a significant increase in the softness of SHS-treated brown rice was observed by using a food texture tester. Results from blinded experiments involving paneists also show that pre-treated brown rice was easier to eat, indicating that pre-treatment of brown rice effectively improved its softness. Functional analysis carried out revealed that SHS pre-treatment increased GABA content of brown rice, however, the antioxidant and total polyphenol contents were maintained. In summary, the palatability and bio functional properties of brown rice treated with superheated steam were improved. This study demonstrated the effectiveness of SHS pre-treatment to increase the utilization of brown rice as food.

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 In this study, we aimed to show the possibility of sake brewing by mixed culture using Gifu University yeast strain GY115-a3 and Gifu Prefecture yeast strain NFG. A large-scale sake fermentation by mixed culture using strains GY115-a3 and NFG produced a unique type of sake that possessed a light and dry taste (values for alcohol, sake meter, and acidity of 16.7%, -3.7, and 1.82, respectively), and a similar malic acid/succinic acid (MA/SA) value (0.46) and content of ginjo-ka as a case of single culture using strain GY115-a3 and strain NFG, respectively. These results indicate that sake brewing by mixed culture of sake yeast strains together with strain GY115-a3 is useful for making a unique type of sake with flavor and taste produced by strain GY115-a3.

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 In this study, I attempted to monitor α-amylase inhibition by various types of tea leaf extracts in sponge cake prepared using honey. I also attempted to ensure that the sponge cake raises to the desired height. α-Amylase was inhibited by green tea and oolong tea, and the height of the sponge cake increased when these tea extracts were added to the batter. As part of the sensory evaluation, I received a positive response from 10 individuals, who found the sponge cake containing honey and tea leaf extracts appealing, implying that the cakes prepared using the aforementioned ingredients would become popular among consumers.

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 Pork is a source of protein that is relatively inexpensive to purchase. The quality of fat, including fatty acids, is related to the deliciousness of pork and varies depending on the feed supplied to pigs. In recent years, n-6 and n-3 fatty acids have attracted attention for their health benefits. The main n-6 and n-3 fatty acids in pork are linoleic acid and linolenic acid, respectively. We have described the variations in linoleic acid and linolenic acid in pork and pork-based dishes.

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[in Japanese]

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