Air borne bacteria in a school kitchen were determined by using the pin hole sampler method for 9 months from April to December, 1978. The plate counts of air borne bacteria ranged from 0.1 to 0.2/l of air in April to June, and in September to November, ranged from 0.4 to 0.5/l. The predominant constituents of the indoor bacteria were gram-positive cocci and gram-positive spore forming rods. Cocci were largely detected from air in May and June, wheareas bacilli predominated in October and November. The main species of bacillus isolates were B. subtilis, B. licheniformis, B. megaterium and B. cereus, and these species were 37.9, 12.2, 11.6 and 8.3% of all bacillus isolates, respectively.

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A study was conducted to determine the effects of temperature and period on the qualities of three kinds of beans during storage, and the effects of temperature and time of soaking and sprinkling on the rate of sprouting of the beans in order to make good bean sprouts. The good bean sprouts were produced when seeds of beans were stored under 0°C and 85% RH for 5-7 months after picking, and they were soaked in water at 30°C for 5 to 7 hours and then sprinkled with water of temperature at 30°C for 15 minutes at 4 hours intervals. Under these conditions, germination rate as % was 80-83% for soybeans and Adzuki beans, and 90-91% for mung beans. The length of hypocotyl was 15-17cm for soybeans and mung beans, and 7-8cm for Adzuki beans. The thikness of hypocotyl was 3.5mm for soybeans, 2.7mm for mung beans, and 3mm for Adzuki beans. In the cases of prolonged storage of seeds of beans at high temperature (10-20°C)rate of water absorption into the beans was low and percent of germination of the beans was considerably low. When the temperature for soaking was low and the period of soaking was inevitably prolonge sprouting of seed of beans became slow and water absorption of the beans became excessive. Then, these beans tend to decay. When the temperature of sprinkling water was low, the lengthening and thickening of hypocotyls of beans became slow. When sprinkling water was exessive, hypocotyls became dark in color. So, the qualities of the bean sprouts were hard to retain marketable condition.

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Effect of sodium hydroxide concentration on the extraction of the proteins from the yeast cell(S. cerevisiae)disintegrated with vibrogen cell mill was examined; 86.3% of the total nitrogen in the cell was extracted with 0.4% NaOH, about 70% of the isolated protein fraction as dry base was proteins and 9.7% was nucleic acid. Asparagine, glutamic acid, alanin, leucine, glycine, and lysine were rich and cystine, methionine and histidine were poor in the amino acid composition of the proteins. The isolated protein fraction has been characterized using an acetic acid-urea polyacrylamide gel electrophoretic system; the fraction consisted of at least 15 protein components, M₁ and M₂ were estimated to have molecular weight of 49, 500 and 36, 500, respectively, on SDS polyacrylamide gel electrophoretical pattern.

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Organic weak bases, imidazole and 2-aminopyridine, were introduced into the electrochemical measurement of the organic acid content in food basedon conductometry. The quantitative acidbase reactions between acetic acid and the bases were found by studying the effect of the bases on the plot of specific conductance vs. the acetic acid concentration. On addition of excess imidazole or 2-aminopyridine, the linear relationship was obtained between the acetic acid concentration and specific conductance. One hundredth molar imidazole aqueous solution system was employed to determine the salt and acetic acid content in mayonnaise. The salt and acetic acid content obtained by the present method agreed accurately with the values obtained by argentometry and alkalimetry, respectively.

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Peeled chestnuts, which were held for more than 30min in water at 50-70°C and subsequently boiled, attained a harder texture than the untreated control. The cause of the hardening effect was investigated in relation to pectinesterase activity of the raw tissues, the characteristics of pectic substances and the content of divalent cations(Ca and Mg ions)in the tissues with or without the pre-heating treatment. Pectinesterase extracted with sodium acetate solution from the peeled chestnuts had an optimum pH and temperature of 8.O and 50°C, respectively. The activity wa shigher in immature fruit than in mature one. The degree of esterification of polyuronides of the tissues decreased by 4 to 8 percent after the pre-heating treatment, though the increased carboxyl groups of the polyuronides were insufficiently combined with divalent cations. The degree of the divalent cation saturation to the free carboxyl groups was higher in less hard tissues. There was no correlation between hardeness of the boiled chestnuts and the degree of saturation of the polyuronides with divalent cations. It was presumed that the pre-heating treatment caused apparently the decrease of the degree of esterification in the polyuronides with-out rapid combination with divalent cations and the resulted lower esterified polyuronides probably resisted to heat-degradation of glucoside bond to inhibit softening of the tissues.

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One of the wastes from agricultural products, draff from coffee-making, was converted to active carbon by treatment with zinc chloride. The optimal conditions for preparing active carbon were examined with regard to temperature and time for activation, and concentration of zinc chloride. Active carbon produced under various conditions, as well as five products commercially available, were compared with each other by iodine, methylene blue and caramel tests according to the methods of Japanese Industrial Standard(JIS). The product prepared at 600°C for 2-3 hours with 100-150%(w/w)of zinc chloride, showed an excellent properties no less than those of commercial products. Therefore, it was suggested that the coffee-making waste could be utilized as active carbon.

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Possibility to keep the freshness of fruits and vegetables by short-term high CO₂ treatment at 20°C was examined. The physiological effect of treatment on tomato fruit was investigated. Exposure to 100% CO₂ for one day was most effective to delay the ripening of tomato fruit, and 6 hour-treatment was also effective. Carbon dioxide was more effective than N₂. Treatment with CO₂ and low temperatures did not lead to accelerate the effect compared with CO₂ treatment alone. There was difference between the effect of treatment on the fruit of different ripening stages: the treatment was effective considerably when CO₂ was applied to the fruit of stages at breaker or light pink rather than mature green one. There were different effects of treatment on the fruit harvested in different seasons including forcing and retarding. Treatment with 40-100% CO₂ for one day was effective to keep the freshness of tomatoes, bananas, pears, broccolies, garland chrysanthemums, and mushrooms. In banana fruit, the shock effect by the treatment with high concentrations of CO₂ was remarkable. In this cace, the best result was obtained in the fruit treated for 3 days. Good quality of pears and broccolies was holden without occurrence of CO₂ injuries for 9 days(100% CO₂)or 5 days(80% CO₂)during storage, respectively.

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Peanut protein was extracted from defatted peanut meal with 0.01M NaCl (pH 8.0)and separated by addition of acetone or ethanol at 60% concentration. Acid-precipitated protein was prepared by adjusting pH of the extract to 4.5 with HCl. Acetone-precipitated protein(AP)and ethanol-precipitated protein(EP)were almost insoluble at pH4.5, but their solubility increased to 90-95 and 63-80%, respectively, at pH7-9. AP and EP were unstable on heating; protein coagulation occurred when the solutions were heated at 98°C for 5min. In the sedimentation diagrams, 14S component was predominant in AP and EP, whereas 9S component was predominant in acid-precipitated protein. By polyacrylamide gel electrophoresis, AP and EP yielded faster-moving bands compared with acid-precipitated protein. Unlike AP, EP was separated into many fractions including large fractions eluted with low NaCl concentrations by DEAE-Sephadex chromatography. From these findings, peanut protein was found to be denatured with acetone and ethanol, and appears to be more susceptible to ethanol than acetone. The amino acid composition of these isolates was similar, although some differences were apparent. AP was slightly high in lysine and EP was slightly low in cystine and histidine and high in tyrosine.

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Solubilization technique of oily substances into micellar solution of protein and carbohydrate was applied to encapsulation of some model volatile substances in combination with vacuum drying process. Eugenol was uniformly solubilized into the aqueous solution of 70%(w/w) corn syrup solids and polypeptone as 1%(w/w)nitrogen, and considerably high retention of eugenol after drying at 60°C was obtained. Granulation of the solidified cake of the solubilizate caused slight liberation of eugenol in fractions of smaller particles and higher eugenol content. However, granulation scarcely affected on encapsulation rate when eugenol content was about 10%. Volatility of eugenol under the air-circulating condition at 60°C was remarkably decreased through the encapsulation process. The encapsulation test of the multi-component system of limonen, linalool, benzyl alcohol and eugenol in the concentration of 14.96g in total to 100g solids showed significantly high retention rates of the components. Based on the gas-chromatographic analysis, they are 92% for benzyl alcohol and over 95% for the other substances in the 24-32 mesh granules.

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