Changes in salt, organic acid (citric acid: CitA and malic acid), and total polyphenol (PPH) contents in each step of the traditional umeboshi production process were investigated and clarified. Next, to develop a production method for umeboshi with low salt content and high functional ingredients, we investigated the effects of CitA addition during the pickling and/or desalination processes and shading from direct sunlight during the drying process on the amount of CitA and total PPHs, respectively. The results demonstrated that the CitA content of pickled umeboshi was highest when CitA was added in both processes, followed by additions only in the desalting and pickling processes. Multiple regression analysis of the results revealed that the CitA content in the pickled umeboshi was more than twice higher when CitA was added during the desalination process than during the pickling process. Shading during the drying process significantly inhibited the reduction of the total PPH content.

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 The current study aimed to determine the changes in the composition of salad onions after heating operations during vacuum packaging. Six treatment conditions, namely, S and 2L size unheated, S and 2L size boiled, and S and 2L size vacuum cooked, were used to determine the impact of heat treatment on salad onion composition, particularly in terms of sugars, organic acids, amino acids, and quercetin glycoside content. The results of our analysis revealed that vacuum cooking promoted less elution of sweet and savory components and quercetin glycosides than boiling. Furthermore, vacuum cooking resulted in greater amounts of nutrients beneficial to the human body, such as GABA, than the non-heated condition. Therefore, our results demonstrate that vacuum packaging of salad onions by food service facilities can be potentially beneficial.

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 This study explored the effects of combining onions and other umami-rich ingredients on the intensity of umami flavor in Japanese cuisine. We aimed to determine whether various combinations of umami-rich ingredients added to foods served in nursing care facilities could reduce the need for salt while enhancing palatability and promoting saliva secretion. To accomplish this, we used a variety of umami-rich components-including bonito flakes, kelp, shitake mushrooms, sardines, and onions-to prepare stock solutions at a concentration of 1 %. We then developed tasting samples by combining two of the stock solutions. Taste assessments were conducted using a taste recognition device that evaluated “fronttastes” (bitterness, astringency, and umami) and “aftertaste” (bitterness, astringency, and umami “richness”) components. We maximized the umami intensity by combining stock solutions from onions and bonito flakes or onions and shiitake mushrooms. Our results suggest that bitterness, astringency, and umami “richness” contribute overall umami strength. The combinations of stock solutions prepared from onions and bonito flakes were then subjected to sensory evaluation.

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 This study aimed to determine the effect of storage conditions on the quality of fruits before natural dropping of the chestnut fruit. Before natural dropping of chestnut burrs, fruits were collected to investigate changes in quality including Brix, free sugar contents, and free amino acid contents at different storage temperatures (1°C, 5°C, 10°C, and 25°C), storage duration (7, 15, and 30 days), and condition (with or without burrs). To investigate changes in fruit quality, the fruits were collected 9 days before the natural drop, 3 days before the natural drop, and ripe fruits were collected from the tree. Chestnuts on the tree increased in Brix free sugar and free amino acid content as they ripened. Cold temperature storage (1°C and 5°C) treatment increased the sucrose and glutamine contents. Thus, the storage conditions of chestnut burrs changed the sweetness, saltiness, and umami of the fruit.

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[in Japanese]

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