In case of odor evaluation of foods by sensory test, the variation among panelists in responses to an odor attribute becomes an issue. This experiment was carried out to examine the training effect of sensory panel using the odor reference solutions. Ten girl students of college were trained as follows. After the explanation of odor attributes of an odor reference solution, the panels sniffed the reference solution and expressed its odor attributes using 43 terms by a 5-point scaling method. This training procedure was periodically repeated five times for 15 odor reference solutions. On the scatter diagram of sample scores by quantification theory III, the sensory scores located far from the scores of image pattern before training, but became more closer after the repetition of training. The odor attributes of the reference solutions remained in panel's memory even after 2months. At the sight of theses catter diagrams as a whole, 15 odor reference solutions were located circularly around the intersection point of two axes, and each sample score after the training shifted toward the position farther from the intersection point. This showed that the odor attributes of 15 odor reference solutions were characterized distinctly by training.

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The influence of fat content and homogenization pressure on physical properties of sour cream were investigated. Using 20%, 30% and 40% fat creams as the starting materials, two-stage homogenization was employed in the range of 1.25-20MPa at the first stage and at 1MPa fixed at the second stage. Hardness, cohesiveness and adhesiveness of the sour creams were evaluated by a texture analyzer. The volume of separated serum was measured when sour cream was stored in a cold place (at 5°C), and the volume of curd was measured when sour cream was added to hot water (95°C<). The results of texture analysis indicated that hardness of sour cream increased with increasing fat content and homogenization pressure. Cohesiveness and adhesiveness decreased. with increasing homogenization pressure. At the same hardness level, cohesiveness and adhesiveness increased with an increase of fat content. The volume of separated serum decreased with an increase of homogenization pressure and, at the same hardness level, it decreased with that of fat content. The formation of curd was promoted greatly with an increase of the first homogenization pressure above 10MPa for all levels of fat content.

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Starch granules were isolated from 13 varieties (30 samples) of rice endosperm cultivated and harvested different years from 1988 to 1991, and characterized by physico-chemical methods. The rice grains were new types including giant-embryo, fragrance, high-amylose, low-amylose and big-grain. The amylose contents of the starches were varied from 10% to 30%. A low-amylose cultivar, Dohoku 53 and a fragrance one, Sariqueen had 7% and 4% difference in amylose content by cultivating in different year, respectively. The rice starches obtained from plants cultivated in Hokkaido and starches from a high-amylose cultivar, Hoshiyutaka showed lower temperatures of gelatinization. The biggest difference in onset temperature of gelatinization by difference of cultivated year was observed in the starches of Sariqueen, which was 5°C. The starches from Hoshiyutaka had a higher solubility in 75°C water than the other ones. The starches from low amylose cultivars showed a higher swelling power, suggesting that more water could be involved in the starches.

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Twentyfive samples of Hiratake(Pleurotus ostreatus) and sixteen samples of Maitake (Grifola frondosa) mushroom cultivated on sawdust substrate beds paired with its substrate beds, which were all of distinct origins, were available. Proximate compositions and mineral contents in these mushrooms and substrate beds were determined. Effect of the sawdust substrate composition on the mushroom composition were examined. In Hiratake mushroom, protein content in fruiting bodies was significantly related to nitrogen content in the substrates. Concentrations of minerals to the fruiting bodies from the substrates were found in K (3.20times), Na (1.64times), P(1.70times), Cu (1.90 times), Zn (2.38times) and Cd (2.75times) but significant correlation between them was only found in Cd. In Maitake mushroom, protein content in fruiting bodies was not significantly related to nitrogen content in the substrates. Concentration to the fruiting bodies from the substrates were found in K (16.51times), Na (6.59times), Mg (1.24times), P (4.04times), Cu (3.37times), Zn (4.10times) andCd (9.26 times) but significant correlation between them was only found in Cu.

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The behavior of hydrogen peroxide (H₂O₂) added to laboratory-prepared salted and semi-dried sardine was investigated. When the soaking solutions containing 1000 and 5000μg/ml H₂O₂ were used, the residual H₂O₂ ranging from 0.18 to 71.9μg/g was detected in sardines after salting and bleaching. The residual H₂O₂ contents in sardines were influenced by the manufacturing method, the amount of H₂O₂ added to soaking solutions and the concentration of sodium chloride in soaking solution. After washing, the residual H₂O₂ ranging from 0.43 to 1.21μg/g was detected in sardines soaked in the solution containing 5000μg/ml H₂O₂. After drying, no residual H₂O₂ was found in all salted and semi-dried sardines. During the manufacturing process of salted and semi-dried sardine, H₂O₂ in sardines was completely decomposed. Catalase-activities ranging from 14.2 to 46.7U/g were detected in surface layer of both thawed raw sardine and prepared salted and semi-dried sardines soaked in the solutions with and without 5000μg/ml H₂O₂. From these results, decomposition and disappearance of H₂O₂ during the manufacturing process of salted and semi-dried sardine seemed to be due to the action of catalase in sardine.

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Biosensors were developed for simple and rapid measurement of tea catechins. The sensor which consisted of tyrosinase-immobilized membrane and an oxygen electrode continued to have a stability problem. The sensor that uses a slice of burdock (Arctium lappa L.) as a substitute for the tyrosinase membrane was stable enough to measure the concentration of catechins in green tea infusion. When the concentrations of catechins in tea infusions were measured by this sensor, the results showed good correlation with the results of the standard method.

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Cassava cortex was successfully used in the induction of linamarase in Aspergillus oryzae in place of linamarin which is an expensive inducer. Induction by cassava cortex was attributed to its linamarin content. However, besides linamarin, some other components in the cortex may have enhanced induction or stabilized the enzyme induced thus resulting in increased linamarase production. Statistical evaluation showed the significant influence (p<0.01) of the combination of cassava cortex and linamarin on the induction.
From this study, the following conditions were found to be optimal for linamarase production: Czapek medium containing 5% cassava cortex powder which was inoculated with 1×10⁸ spores (precultured for 48h) per 100ml medium and incubated at room temperature in a rotary shaker at 100rpm for 24h. Strain SA 1 yielded 0.05units/ml of crude linamarase sample.

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This study was conducted todetermine the optimum combination and addition amount of natural stabilizers in order to improve the foam stability and texture of starch-based frozen pudding. The following seven natural stabilizers were investigated; gelatin, locust bean gum, xanthan gum, carrageenan, guar gum, pectin, and tamarind gum. A total of 16 frozen pudding samples were prepared by assigning the combination and amount of stabilizers through experimental design using orthogonal factorial arrangements. Foam stability, texture and starch particle size were evaluated. As a result, it was found that adding gelatin and locust bean gum significantly improved the foam stability without inhibiting starch particle swelling. The optimum amount of those stabilizers to be added was determined through two factorial experiments. The frozen pudding using this optimum formula was found to be satisfactory in terms of the foam stability and texture. The effects of individual stabilizers on the foam stability, texture and starch particle swelling of the frozen pudding were also discussed.

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