Simulated-mayonnaise o/w emulsions prepared with diacylglycerol (DAG) were compared with triacylglycerol (TAG) emulsions in order to clarify the emulsifying properties of DAG. The fatty acid composition, surface tension, viscosity, color and other properties of DAG were similar to those of TAG. Emulsions having an oil-volume fraction of 0.65-0.80 were prepared with oil, egg yolk and 3.5% (v/v) acetic acid. The emulsions prepared with DAG showed a higher yield value, higher consistency index and lower flow behavior index than those prepared with TAG. The median diameter of the oil globules in the emulsions prepared with DAG were smaller than those in the emulsions prepared with TAG. It was also found that the interface area of each emulsion prepared with DAG corresponded to a higher viscosity than that for the emulsions prepared with TAG. It was concluded from these results that the emulsifying properties of DAG in a concentrated o/w emulsion system were superior to those of TAG.

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The effect of adding a bamboo charcoal extract to rice cooking water was studied. Cooked rice with the extract of bamboo charcoal was evaluated as being more tender and better overall than that cooked in water alone. Cooked rice with the bamboo charcoal did not suffer from an increase in hardness during preservation at low temperature. This result suggests that the bamboo charcoal extract affected the texuture of the cooked rice. Bamboo charcoal soaked in water, gave a strongly alkaline solution in a comparatively short time. When the soaking time was prolonged for 2 or more days, the conductivity was substantially increased. A substantial proportin of total sugar and protein was liberated in the cooking water of rice containing the bamboo charcoal extract. These results suggest that the use of bamboo charcoal increased the pH of the cooking water and accelerated the gelatinization of rice starch.

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The rheological and microstructural properties were examined of heat-induced gels of thick and thin egg whites obtained from fresh (0-day eggs) and stored eggs (25°C,7-and 14-days eggs). The measurements of textures (hardness, cohesiveness and gumminess) and dynamic viscoelasticity (storage modulus G', loss modulus G" and tan δ=G"/G') of gels prepared by heating at the final temperature of 85°C showed that the gels became softer, more elastic and more sticky with increasing of the storage period, and gels from thick egg white in the 0-and 7-day eggs were slightly softer than ones from the corresponding thin egg white. From the G' values obtained during heating from 20 to 85°C, gelling temperatures were found to increase with storage indicating similar changes between the thick and thin egg whites. The microstructural characteristics of the gels observed with a scanning electron microscope indicated that the spherically shaped structure attached to the network by protein aggregates changed, for stored eggs, to crystal-like structure having larger pore size.

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The diameter of starch granules and bubbles in surimi has been shown to very with the heating temperature. In this study, whether the breaking stress and breaking strain are correlated with the diameter of starch granules and bubbles in surimi was determined. Potato starch, processed potato starch, K-1, MR 200, Batter # 0, MT 01 and HPpotato were added separately to surimi, which were then cooked at 60-100°C for 20 min. Starch granules and bubbles increased in diameter by heating. Increase in diameter of starch granules were positively correlated with the breaking stress in surimi including potato starch, K-1, MR 200, MT 01 or HPpotato, but not in surimi including processed potato starch or Batter # 0. Increases in diameter of starch granules were negatively correlated with breaking strain in surimi including MR 200 or HPpotato, but not in surimi including the other starches. Increase in diameter of bubbles were positively correlated with breaking stress in surimi including five kinds of starches separatly, but not in surimi including potato starch or Batter # 0.

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The aroma characteristics of roasted sesame oil prepared by supercritical carbon dioxide extraction (SCE) were examined by a GC analysis of the volatile head-space gases, and by sensory tests on the SCE extracts, the expelled extract (EE) and ground seeds (GS) of roasted black sesame. The GC analysis showed that the contents of such highly volatile compounds as methanthiol, acetaldehyde and methanol were reduced to below a half by the extraction process. The SCE extracts had similar aroma components to thouse of GS. The earliest SCE fraction contained twice the content of aroma compounds as that in EE, and four times that in GS. EE had different aroma components from those of the other samples, containing more pyrazines, furans and pyrrole. The sensory tests showed no significant difference in the aroma of the SCE fractions from thouse in GS, and a preferable and stronger sesame-like aroma to that of EE. These results indicate that the SCE method is effective for extracting sesame seed oil with the characteristic aroma of roasted sesame seeds.

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A sensory test was carried out on food prepared by using triacylglycerol (TG) oil and diacylglycerol (DG)-rich oil, and the change in chemical properties of the oils with heating time was measured. The TG oil was rated higher than the DG-rich oil in the overall sensory evaluation for tempura, frying, kara-age, dressing and cookies. The acid value, carbonyl value and viscosity of the oils when used for frying increased with heating time, the values for the DG-rich oil being higher than those for the TG oil. The peroxide and iodine values were no different between the two oils, although the coloration of the DG-rich oil was earlier and deeper than that of the TG oil. The total tocopherol concentration of the DG-rich oil was very high due to the supplementation, but markedly decreased with heating time. Overall, the sensory evaluation results were better for the TG oil than the DG-rich oil, and the former was more stable than the latter for flying.

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We examined the image of Mosso rice (boiled rice molded with a Mosso mold in traditional Japanese style) by showing it to Japanese and Korean women students. Five different shapes of Mosso rice were used and presented on lacquered plates in 2 different colors (black and vermilion). The image was examined by using 30 pairs of antonymous adjectives by the SD method. A factor analysis of the result was performed by using SPSS software. The significant factors extracted from the pairs of antonymous adjectives were assessed. In the case of the Japanese, they were "emotional" and "gorgeous", and of the Koreans, "favorite" and "conspicuous". The appreciation of the image of Mosso rice by the Japanese panel was the sense of season and celebration that was originally displayed by Mosso rice, while the Korean panel appreciated it simply through the image of shape and favor. This result suggested the appreciation of the shape of food and the color of the plate were influenced by the food culture of the country.

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Gray water is one of the principal origins of water pollution. A questionnaire survey was conducted of people who cooked at home in 1999 to investigate their awareness of and efforts to reduce pollutants in kitchen waste water. Although awareness of wa ter pollution was not low (41%), the degree to which kitchen waste contaminates the water was not correctly recognized. Small garbage was usually flushed away with water and collected in a garbage basket when there was concern about organic waste. Frying oil was disposed of correctly, while liquid waste such as drain water from boiling noodles was poured away. About 60% of respondents used dishwashing detergent "undiluted, quantified at a guess, or put directly on a sponge". Wiping away the residue on dishes before washing was practiced in only about 30-40% of homes which suggests that its effect was not generally recognized. Those respondents with an awareness of water pollution tended to make many efforts to reduce the pollutants in kitchen waste water.

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