Changes in the chemical properties that occur during the cooking of rice, and the texture and palatability of cooked rice were examined in three kinds of brown rice: low-amylose and giant-embryo rice "Kinnoibuki", low amylose content rice "Takitate", and normal rice "Hitomebore". Two different soaking durations were tested wherein all rice grains were soaked for 1 hour, and for 24 hours, prior to cooking. For the soaking duration of 1 hour, brown rice "Kinnoibuki" showed the highest rate of water absorption of rice grains, solid content of cooking water, and cracking ratio of the rice grain coats. The raw and cooked brown rice "Kinnoibuki" also showed the highest content of free amino acids and sugars, among the three rice cultivars. Furthermore, due to its low amylose content and giant embryo characteristics, the taste and texture of cooked brown rice "Kinnoibuki" were significantly enhanced with the longer soaking time of 24 hours.

Plant-based foaming and emulsifying agents can be promising to produce clean-label healthy food products. To examine the potential use of such products in food processing and cooking, various micronised dried plant products, such as grains, beans, and seaweed, and shiitake mushrooms were added to reduced-sugar meringues and used to prepare mayonnaise-like egg-free dressings. The drip volume from the reduced-sugar meringues prepared using plant products decreased significantly compared to those from the control reduced-sugar meringues. The micronised dried glutinous rice and shiitake along with vinegar and NaCl were able to emulsify salad oil, which was then used to prepare mayonnaise-like emulsions. Moreover, the glutinous rice-based emulsion was notably stable against oiling-off, which can be partially attributed to Pickering stabilisation, according to CLSM observation. The deproteinised glutinous rice and shiitake products could not stabilise meringues and dressings, indicating that proteins of these particles might be strongly associated with stabilisation mechanisms.

The Chinese yam (Dioscorea polystachya Turcz.) is a common starchy component of the Japanese diet and is often eaten raw. We evaluated resistant starch (RS) content of the Chinese yam and also investigated the effects of cooking temperature and cooking style on RS. The Chinese yams were cut into half-moon slices or grated, and both types of cuts were studied in the raw as well as cooked forms. They were heated to 70°C or boiled, and then analysed for the RS content. The RS content was found to be five-to-six-fold higher in raw Chinese yam than that in the cooked one. Furthermore, the RS content was 1.7-fold higher in half-moon slices of the raw Chinese yam than that in the grated yam. These results suggest that raw Chinese yam contains a large amount of RS2, which is highly resistant to enzymatic hydrolysis, and that much of this starch is gelatinised when cooked. Furthermore, it was suggested that the cooking style of the Chinese yam might also affect the amount of RS within.

Recent reports indicate difficulties in passing on ceremonial, traditional, or local speciality foods to young people. In order to share these foods with younger generations, it may be necessary to examine the differences in preferences among generations and living areas, and to identify the challenges involved in the transfer of regional cuisines from one generation to the next. This study examined the attitudes and behaviour of Japanese people towards the consumption of sushi (hayazushi), which has been passed down through generations as a ceremonial dish, traditional cuisine, and local speciality food. It also compared sushi rice preferences among different generations and living areas. Research showed that the most frequent type of sushi consumed is ‘hand-shaped sushi', regardless of the generation. The most common method of consuming sushi among the younger generations is ‘going to conveyor belt sushi restaurants'. The study also revealed that the younger as well as the older generation consume sushi as part of their daily meals, and preferences for sushi rice vary among generations and living areas. This study emphasises the necessity of conveying the cultural history of local cuisines to the younger generations and of making regional cuisines more appealing by adopting certain changes—in light of shifts in preferences for sushi—that preserve the original characteristics of traditional cuisine, such as a change in the seasoning process.

In this study, we examined the efficiency of calcined scallop shell calcium (calcined shell Ca), strongly alkaline and odourless when dissolved in water, on the palatability of stored rice. We washed the rice five times and used the calcined shell Ca solution (0.03% [w/v]) for the second wash.

Although the rice-washing solution was strongly alkaline (approximately pH=12), the pH returned to neutral when the rice was soaked before cooking. We observed no difference in the surface structure of the rice grains after washing, but the fat acidity of the rice washed with calcined shell Ca was significantly lower than that of the control. Our paired difference tests showed no significant difference in hardness, stickiness, or sweetness between the two samples. Our time-intensity curve analysis showed that washing the stored rice with calcined shell Ca ameliorated its stale flavour by approximately half.