New uses for rice flour are being investigated to increase the consumption of rice in Japan. Rice flour bread was prepared in this study with silk fibroin or xanthan gum added, and the properties were examined to compare with those having no gluten additive (control). The specific volume, hardness and adhesiveness were all higher in the rice flour bread with silk fibroin added than for the control (p<0.05). Xanthan gum added in a sol with the water content increased from 105% to 115% resulted in a higher, specific volume and lower hardness than the control values (p<0.05). The combination of silk fibroin and rice flour paste gave a higher score in the sensory evaluation than the control score (p<0.05). Leaving the dough for 24 hour after preparing it with no additive (control) and with silk fibroin added, respectively increased the specific volume (p<0.05), and resulted in a finer-grained structure. The sensory evaluation of the control bread showed significant preference for the sample obtained by leaving the dough after its preparation.

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We found that the degree of the color (Abs. 430 nm) was correlated with the intensity of emulsification in commercial soy sauce. Heating the glucose supplemented soy sauce at 75℃ increased its degree of color (Abs. 430 nm) and also the intensity of emulsification as the heating time was increased. Next, We then investigated the intensity of emulsification of 20 kinds of melanoidin derived from heated mixtures of glucose and 20 amino acids. The alanine-, glycine-, and threonine-glucose melanoidins were found to have a stronger intensity of emulsification among the 20 kinds of melanoidin. These results suggest that the melanoidins derived from these three amino acids might be one of the factors responsible for the stronger emulsification intensity of soy sauce.

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The effect of trehalose on preventing crumbling was investigated when boiling red kidney beans (kintokimame). Superfine sugar was used as a sweetening control. The beans were immersed in hot water for 2 hr, trehalose or sugar was added, and the beans were boiled with an IH cooking heater for 40 min. The crumbled state, rupture property and sugar concentration of the beans cooled for 1 hr after boiling were then measured. The beans boiled with trehalose tended to soften earlier than those boiled with sugar; the former tended to crumble much less than the latter. The rupture properties of the beans boiled with trehalose suggested that they had been softened by the water retentivity of trehalose. There was no difference in the sugar concentration and tissue microstructure of beans boiled with either trehalose or sugar.

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The contact dehydration sheet (CDS) method is typically used to determine the salting and drying conditions for producing medium-dried low-salt seafood from several species of fish. Seafood samples dried by the CDS method were compared with those dried by conventional mechanical dehydration to examine the daily change in viable cell count during low-temperature storage (5°C). The viable cell count of seafood dried by the CDS method was significantly lower than that dried by either conventional mechanical dehydration or ash treatment that is also used for producing dried seafood. The reasons for this are likely to be the higher temperature (27°C) used for conventional mechanical dehydration, as well as the possible effects of secondary contamination by bacteria inside the drying oven and by airborne bacteria. CDS adhered to the fish during the production process, limiting the accessibility to airborne bacteria, while dehydration and drying at a lower temperature (5°C) delayed the growth of bacteria. Ash treatment is difficult to use and its dehydration efficiency is lower than that by the CDS method; it involves only gradual dehydration, and ash treatment is therefore presumed to be vulnerable to high contamination by various bacteria during the production process. The results indicate the CDS method to be superior to other typical methods for dried seafood production in terms of its microbiological control.

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We evaluated the hydroxyl radical scavenging ability of instant coffee by the ESR spin trapping method, using 5-(2,2-dimethy-1,3-propoxycyclophosphoryl)-5-methyl-1-pyrroline N-oxide (CYPMPO) as the spin tapping reagent. This method generated very pure hydroxyl radicals by illuminating a phosphate buffer solution containing H₂O₂ and CYPMPO with an Hg-Xe arc lamp. The ESR adduct signal was sensitive and very stable. We conclude that instant coffee had high hydroxyl radical scavenging ability.

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Samples of iri-sake and haya-iri-sake were reproduced according to cookery books of the Edo period. An analysis of the component properties and sensory evaluation of these samples were conducted. The characteristics of iri-sake were a mixed taste of well-aged sake with IMP (umami) and citric acid (sourness) respectively from dried bonito and pickled plum. In contrast, haya-iri-sake showed the taste of well-aged sake with added glutamic acid (umami) and acetic acid (sourness) respectively from soy sauce and vinegar. The salt concentration of both iri-sake and haya-iri-sake was lower than that of soy sauce. The storage properties of iri-sake showed gradually increasing turbidity and yellow property (b*) according to the length of storage. This phenomenon was most marked with storage at 35°C, although the change was slight at 5°C. A sensory evaluation showed the greatest palatability for soy sauce with sliced raw fish, whereas iri-sake was the lowest among all the seasonings tested. The palatability of haya-iri-sake with cucumber and spinach was higher than that for the other seasonings. Haya-iri-sake was found to be the most accepted and utilized seasoning according to present dietary habits.

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The expansion of rice starch heated at 80°C was controlled by employing a sucrose solution stronger than 22.9% (w/w). The weak iodo-starch reaction shown by the supernatant of the reaction mixture suggested that a 42.2% (w/w)sucrose solution inhibited the collapse of the rice starch. We experimentally produced rice-an paste from 20 g of rice flour by heating it with 25 g of sucrose and 55 g of distilled water at 80°C for 1.5 hours. The chewiness (koshi) and stickiness of the rice-an paste resembled that of azuki bean paste. The apparent sugar density was increased 5-15% by heating the rice flour (10-24% w/w) and sucrose solution (25% w/w), suggesting that the rice flour absorbed water by 1-1.5-fold.

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The effectiveness of cutting up food for the elderly was examined, employing eight kinds of food as samples considered difficult for the elderly to masticate based on instrumentally measured data, an organoleptic evaluation, and the frequency of mastication.
Seven samples (apple, cucumber, boiled daikon root, boiled konjack, mushi-kamaboko, cuttlefish and boiled common octopus) were significantly softened by being cut up, while boiled carrot root was not. The frequency of mastication of all samples which had been cut up was significantly low (p < 0.05), the decrease ratio for cuttlefish and boiled common octopus being particularly high. Although those samples that had been cut up were not liked by the elderly, cutting up boiled konjack block and cuttlefish induced little sense of discomfort.
Cutting up of cuttlefish proved to be an effective preparation method which did not lead to any sense of discomfort for the elderly, and decreased both the food hardness and frequency of mastication.

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