The effect of sucrose addition on the gel strength of 15 wt% cornstarch (13.0 wt% on dry matter basis) was studied using differential scanning calorimetry and uniaxial compression tests. Sucrose at concentrations of 0–50 wt% was added before and during heating of the cornstarch dispersions.
When sucrose was added to the cornstarch, gelatinization occurred at higher temperature and the gelatinization enthalpy was increased, indicating suppression of the gelatinization process. However, cornstarch gels with sucrose became more resistant to deformation and deformable than the control. These phenomena were pronounced when sucrose was added before heating the starch dispersions.
Furthermore, it was found that, upon storage of cornstarch gels in which sucrose was added before and during heating, the amount and rate of change in the gel strength was greater than that of the control. However, addition of sucrose at 20 wt% or higher before the heating step resulted in fewer changes in the gel strength during storage, indicating the retardation of starch retrogradation. Moreover, adding sucrose to gels during heating led to fewer changes in the gel strength during storage.
We investigated the effects of storage on the hardness, L-DOPA content, and tissue structure in Mucuna beans (Mucuna pruriens). Hardening defect tended to occur as a result of storage at high temperature and high humidity (30°C/75% RH), at low temperature and low humidity (4°C/35% RH), and at room temperature (20°C/60% RH). Beans that were kept refrigerated (4°C/80% RH) showed the smallest change. The L-DOPA content of aged beans was hardly changed even when stored at high temperature and high humidity, but cooking reduced the amount to about one third. Analysis of the pectin fraction in alcohol insoluble solids revealed that the hardening of Mucuna did not involve the formation of crosslinks by pectin and divalent cations, suggesting that there was an interaction between Ca2+ and cell wall polysaccharides, such as hemicellulose and cellulose. Furthermore, differential scanning calorimetry and scanning electron microscopy suggested that the denaturation of proteins around starch granules disturbed swelling, resulting in insufficient gelatinization of the starch during heating.
An increasing number of elderly people in Japan are suffering from symptoms of constipation and poor nutrition. Consumption of okara, known for its high dietary fibre and protein content, has shown promise in alleviating the symptoms of constipation and poor nutrition. The present study aimed to develop a high-fibre protein food product for elderly people. Fish balls (tsumire) made of fish-paste with okara powder content of 5, 8, and 10% (w/w) were prepared and a quality assessment was conducted. The results of the sanitary testing assured the safety of the manufacturing process used in the present study. The determination of nutrient content and the results of measuring light intensity and colour showed increased dietary fibre content and b*value with increasing okara powder content. On the basis of the texture property value and the fact that it meets the physical property standards of nursing care foods, an appropriate supplementation ratio of okara powder was determined to be 8%. In addition, the analytical sensory evaluation revealed that the product with 8% okara was softer and stickier than the product with 0% okara. The properties of the 8% okara product were not favoured in the taste sensory evaluation but the sensory evaluation panel used in the present study consisted of young individuals. The tsumire with 8% okara powder developed in the present study are most likely a food product that even elderly people can safely consume as a source of dietary fibre.
I focused on the dietary customs of red seabream (Pagrus major) in the Okayama Prefecture of Japan from the Edo period to the present. There are many kinds of sea bream, but red seabream with a long body were given as offerings to the gods.
Red seabream were also used as offering dishes and trade items in the Middle period. In the Edo period, red seabream were used in feasts and everyday meals for people of high-status or were offered when serving guests of high positions.
This dietary habit was used in various events such as New Year, Rice Planting, wedding days, and so on until the middle of the Showa period. These dietary customs at New Year and the special traditional dishes (e.g., Ohitiya, Hyakuniti, and Tyojyu) have been transformed and experienced by their own family from generation to generation.
Previous studies have noted the necessity of exposure to local specialty experiences from early developmental stages, such as infancy. Based on this, a picture book presenting the local specialty in Yamaguchi Prefecture was developed, and kindergarten teachers used and evaluated it in order to confirm its usability. Many kindergarten teachers, including those without knowledge of the presented local specialty, were willing to use the picture book during reading sessions with children. They also regarded it as suitable for students aged 4-6, implying the feasibility of food education, such as knowledge about the local specialty, for pre-schoolers. Children who looked at the picture book while the teachers read it out showed positive reactions, such as "Looks delicious!" and "Great!" Based on these results, the development of picture books presenting the local specialty may be useful to promote children's interest in meals and dishes, in addition to providing opportunities for them to see and learn about such food.