In this study, the distribution of amylopectin chain length and gelatinization properties of starches prepared from barley (BS), sorghum (SS) and koshihikari rice (KS) were investigated. The average chain lengths defined by the sum of Fr. II and Fr. III values were 32.9 in BS and 31.7 in SS. These values were longer than that in KS (21.6). The contents of long chains with average lengths of 60 or more were 13.3mol%, 6.7mol% and 8.8mol% in BS, SS and KS, respectively. Therefore, the long chain content in BS was higher and that in SS was lower than that in KS. The contents of short chains with average lengths from 10 to 20 in BS and KS were high. On the other hand, the short chain content in SS was less than 10. The distribution of amylopectin chain length was evaluated using Fr. III /Fr. II ratio. The Fr. III/Fr. II ratios were 3.93, 2.82 and 3.22 in BS, SS and KS, respectively. The swelling power and solubility of BS were than those of SS and KS higher. The swelling power and solubility of SS were respectively lower and higher than those of BS and KS. The maximum viscosity and breakdown, measured using a rapid viscoanalyzer, were the highest in BS among the three starches, and those of SS were the lowest. However, the final viscosity of SS was higher than the maximum viscosity.

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When udon (Japanese noodles) and Chinese noodles were prepared from flour containing whey protein, the hardness, and tensile strength of the boiled noodles increased. When the physical properties of udon and Chinese noodles boiled after storage at -20°C were measured, the changes in hardness, tensile strength and extensibility induced by freezing were suppressed in the whey-protein-added group more than in the whey-protein-free group. These results indicate that the addition of whey protein suppresses freezing-induced changes in the quality of food products processed using wheat flour. The bread prepared from flour containing whey protein was harder, more elastic and softer when chewed. manju (buns with bean-jam filling) prepared from flour containing whey protein retained their optimal hardness for a prolonged period and had a higher elasticity and a higher viscosity compared with manju made from flour without whey protein. Thus, manju containing whey protein remained elastic even 24 hours after production. In the whey-protein-added group, the surface of manju remained glossy, without undergoing cracking, and had a better appearance, thus elevating the quality of manju. In the organoleptic test, all the food products processed using wheat flour containing whey protein were appraised better than those processed using wheat flour free of whey protein.

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The effects of various frying parameters on the quality of vacuum-fried carambolas were investigated. The three-variable three-level fractional factorial design response surface methodology was used to combine the operation conditions, and process variables including syrup-soaking time, frying temperature and frying time. The response variables were based on the overall acceptability determined through sensory evaluation; the highest overall acceptability was obtained by the combination of syrup-soaking at 30° Brix for 1 hour, and then vacuum frying at 108°C for 46 min. Model functions were verified as being adequate, using an optimum combination of syrup-soaking time, frying temperature and frying time. The result showed that vacuum-fried carambolas have good quality.

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The antioxidative ability and sensory characteristics of camellia oil were studied, to elucidate its potential as an edible oil. The measurement of its peroxide value (POV) showed that camellia oil was stable for more than 3 months at 40°C. The filtrate containing antioxidative substances was fractionated using column chromatography, and the fractions active toward Folin-Ciocalteu reagent were collected and isolated in two materials. HPLC showed that the first material was essentially composed of one compound and the second of three compounds. The NMR spectra of the two materials were similar to each other. The peaks in the aromatic region were superimposable on those of kaempferol, and the presence of a kaempferol moiety was strongly suspected. FAB-MS spectra showed that the molecular weights of the four compounds regularly increased by 100. Detailed structures of these compounds are now under investigation. Sensory evaluation of camellia oil in terms of its color, flavor, taste, and total evaluation was carried out. Although dressings prepared using without heat treatment were not preferred, fried spaghetti and fried potato using heated camellia oil were preferred over those prepared from salad oil with a significant difference.

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Methods of long-term storage of Hiratanenashi persimmons packed in plastic film were investigated. We initially studied the effects of different methods of removing astringency on the storability of the fruit. Three methods were compared : a) storing persimmons individually packed in plastic film at 1°C after treatment with elevated carbon dioxide gas (CTSD method) to remove astringency; b) packaging persimmons with reagents for removing astringency and keeping them at 20°C until astringency removal, then storing them at 1°C; and c) packaging persimmons with or without reagents for removing astringency and storing them immediately at 5°C. We found that persimmon softening during storage is clearly retarded by method a), resulting in a long storability of the fruit. We then studied the effects of storage temperature (1°C and 5°C) and the presence of an ethylene absorber on the storability of persimmons individually packed in plastic film after removing astringency (method a)). The storability of the fruit stored at 1°C was longer than that of the fruit stored at 5°C. A positive effect of the presence of an ethylene absorber on the retardation of persimmon softening during storage was observed at 1°C and 5°C. From these results, we conclude that the individual packing of persimmons in plastic film ar 1°C after astringency removal is effective for the long-term storage of this fruit.

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