The effect of microwave heating on pasteurization of rice cake, bread, rice ball and chinese noodle was studied. The internal temperature during microwave heating was determined with chromel-alumel thermocouple, and the surface temperature was measured with thermolabels. A polyvinylidene chloride wrap made the surface temperature uniform. Propagation of mold in rice cake, bread, rice ball and chinese noodle during storage at 30°C for 20 days could be inhibited by the microwave heating for 20-40s. The temperatures of samples reached 50-90°C after the heating. The rate of decrease in weight of samples during microwave heating was below 2.0%. A polyvinylidene chloride wrap repressed the decrease in weight, and prevented the contraction and deformation of the samples. Escherichia coli inoculated into bread, rice ball and chinese noodle could be completely destroyed by the microwave heating for 20-40s. E. coli was, however, recovered even after the microwave heating for 40s when inoculated into rice cake. A polyvinylidene chloride wrap slightly increased the effect of microwave heating on the destruction of E. coli inoculated into rice ball.

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Two phospholipid acylhydrolases of pI 5.4 and 9.5 in rice bran were purified by precipitation with ammonium sulfate and column chromatography on n-decylamine-Sepharose 4B, phosphatidylcholine-AH-Sepharose 4B and isoelectric focusing, up to the specific activity of 119 and 953-fold, respectively. The main phospholipid acylhydrolase (pI 9.5) showed estimated molecular weight of about 40, 000 when determined by gel filtration on a TOYOPEARL HW-50F column. The enyme had optimum pH of 8.0-9.0 and showed the highest activity at 37°C. There was an obligatory requirement of calcium ion and 0.2mM of calcium ion was essential for maximal activity. It was stable below pH 8.0 and 30°C, inhibited by Al³⁺, Co²⁺, Cu²⁺ and EDTA.

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Flavor preference of juice blends of Satsuma mandarin and Shekwasha jiuice was evaluated by sensory test with respect to blending ratio, juice content, acidity and Brix degree. Blended juice beverages of 10% and 20% juice were prepared from the Satsuma mandarin-Shekwasha juice mixed at 9:1, 7:3 and 5:5 ratios. The beverages adjusted to the prescribed acidity and Brix by adding citric acid and sugar were served to panels. (1) High preference scores were given in 10% juice blended at 9:1 ratio, with 0.55% acid and 14.0° Brix, and in 20% juice of the same blend, with 0.55% acid and 12.5° Brix. (2) Blended juice beverages of Satsuma mandarin and Shekwasha were preferred significantly compared to beverages made from their juice alone.

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The inhibitory activity of adipic acid on 10 strains of yeasts and 33 strains of food spoilage bacteria including 6 strains of lactic acid bacteria was investigated. The following results were obtained. (1) Adipic acid protracted the lag phase, extended the mean generation time and decreased the maximum number of cells of Escherichia coli at pH 5.0. (2) When the pH of liquid medium was adjusted by adipic acid, the growth of food spoilage bacteria was inhibited between pH 4.2 and 5.2. (3) No significant inhibitory effects of adipic acid on food spoilage bacteria were observed at pH 6.0. However, growth of the most tested bacteria was inhibited with the concentration below 0.2% at pH 5.0. (4) Minimum inhibitory concentration of adipic acid on the growth of lactic acid bacteria were 0.4-1.8%. Therefore, it seemed difficult practically to prevent the growth of lactic acid bacteria completely by the sole use of adipic acid. (5) Growth of yeasts was scarcely affected with the addition of adipic acid.

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A simple method for determining vitamin D and provitamin D in fish meat was developed by using high-performance liquid chromatography (HPLC) with UV detector (265nm). After the crude fat egtracted with chloroform-methanol was saponified at room temperature, the unsaponified fraction was subjected to HPLC. Vitamin D₂ and D₃, and provitamin D₂ and D₃ were separated on a column packed with an ODS using CH₃CN-MeOH (80:20) as an eluent. The trace amounts of vitamin D₃ and provitamin D₃ were found in mackerel and saury muscles.

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Animal and plant protein-derived seasoning was intended to develop. On preparation of the seasoning it was intended that the salt content should be 8 to 9 times the total nitrogen content and the formol nitrogen content should be approximately 60% of the total nitrogen content in order to characterize with the mild taste of peptides. The mixture of bonito meal and soybean meal was hydrolized with hydrochloric acid at 120°C, neutralized to pH 5.0 with sodium carbonate and filtered. The filtrate was used for analysis and sensory test as the seasoning sample. The appropriate condition of preparation was as follows: bonito meal: soybean meal 4:6, 3 times amount of 4.5N hydrochloric acid and 12 hour-hydrolysis. The seasoning sample thus prepared gave distinctively rich taste and flavor, which were further improved by the treatment with 0.05 to 0.1% amount of active carbon. Light yellow powder product with good reconstitution properties was obtained by spray drying.

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Three kinds of rice bran, Aka, Naka, and Shiro brans were defatted by extraction with supercritical carbon dioxide (SC-CO₂). More than 80% of crude fat of the Aka bran was extracted with SC-CO₂ at 200atm and 40°C. The oil extracted with SC-CO₂ was lighter in color and contained less phosphorus than that extracted with hexane. Oryzanol was found to be extracted from rice bran with SC-CO₂.

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Fish jelly products were prepared from whole lizard fish and leached meat stored in ice, and leached meat and surimi stored at -20°C. K value, pH, trimethylamine oxide-nitrogen (TMAON), dimethylamine-nitrogen (DMA-N), formaldehyde (FA), total volatile basic nitrogen (TVB-N) and viscosity of the meat were determined during storage. Gel-strength, folding test and organoleptic elasticity of jelly products prepared from the meat were measured. From these results, the available terms of ice stored whole fish, ice stored leached meat, -20°C stored leached meat and -20°C stored surimi for fish jelly products were estimated to be about 2-3 days, about 1 week, less than 1 week and more than 1 month, respectively. Frozen surimi containing 3% sucrose and 0.2% polyphosphate can be available for relatively long period as materials for jelly products.

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Studies were undertaken to analyse the changes in the composition and concentration of volatile compounds after thermal processing of apple juice and to evaluate the suitability for processing of five main cultivars in Japan. Juice yield of the cultivars examined ranged from 65.7% in 'Kogyoku' to 77.2% in 'Hatsuaki' throughout the processing. Seventy to 80 kinds of volatile compounds were detected in chromatographic peaks of which 39 compounds were identified by gas chromatographmass spectrometry. The compounds of each class included 27 kinds of esters, 6 of alcohols, 2 of aldehydes, 2 of hydrocarbons, a phenol and an acid. Average percentage of retention of each class of volatile compounds of the five cultivars was highest, 71.9%, for the alcohols, followed by 50.7% for the esters and 30.5% for the aldehydes. Total amounts of volatile compounds recovered after thermal processing were highest in the cultivar 'Kogyoku' amounting to 7.58ppm followed by 'Hatsuaki' with 5.83ppm, 'Mutsu' 3.20ppm, 'Golden·Delicious' 1.44ppm and lastly 'Fuji' with 1.41 ppm. From these results, it was apparent that the higher concentration of volatile compounds in the juice of cultivar 'Kogyoku' and related cultivar 'Hatsuaki' after thermal processing, accounted the higher suitability of juice making of these cultivars.

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