Gelatinized and polished-rice were stored for 16 months at the room temperature and 35°C. After storage, the sensory attributes were examined with regard to the storage condition. The results were at followes; 1) According to the sensory evaluation by the seven point scale on the appearance, odor, taste, hardness, adhesiveness and overall evaluation of cooked rice during storage, gelatinized-rice stored at room temperature showed the least deterioration, resulting in the highest evaluation scores for each senesory attribute except for odor. 2) The effect of the three factors, that is, storage period (A), kind of rice (B) and storage temperature (C), on the sensory attributes of cooked rice was evaluated by means of analysis of variance with three-way-layout method. A and C were significant at 1% level for each sensory attribute and B was significant at 5% level for appearance and hardness. Interaction between A×B and A×C for all except for hardness were significant at 1% level for each sensory attribute, and that between B×C was significant at 1% level for appearance and overall evaluation and at 5% level for taste and adhesiveness. 3) The correlation coefficients between sensory attributes showed the significant correlation for all of them. It was recognized that overall evaluation was influenced mostly by taste and adhesiveness and appearance, subsequently. The relation between overall eValuation (Y) and sensory attributes (taste: X₁, adhesiveness: X₂, appearance: X₃, hardness: X₄ and odor: X₅) was explained enough by means of multiple regression equation; Y=0.002+0.320 X₁+0.213 X₂+0.201 X₃+0.167 X₄+0.137 X₅.

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Oxygen absorption on linoleate by a halotolerant yeast, Saccharomyces rouxii IY-5 was examined with bovine serum albumin-linoleate complex. The maximum oxygen absorption was observed on the yeast cells harvested at the late log phase. At the initial stage of oxygen absorption on linoleate, it increased linearly with time or with cell concentration. From the incorporation assay of linoleate Km was 42.0μm and Vmax was 2.17nmole/mg min. Optimum pH of transport was 7.5. Examination by a Warburg manometer revealed that 1-¹⁴C-linoleate was degraded to ¹⁴CO₂, which was the indication of the linoleate oxygen absorption by S. rouxi IY-5. Oxygen absorption on linoleate was measured by Biooxygraph with an oxygen electrode. Optimum pH of oxygen absorption was 4.0, which was different from that of incorporation. From the data of the substrate specificity, the oxygen absorption was remarkably high on free acids and methylesters of linoleate and linolenate as substrates. Glucose did not work to stimulate the oxygen absorption on linoleate though it was even a better substrate than linoleate. The cells grown in the media with 1M NaCl Showed high oxygen absorption on linoleate in the same or lower concentration on NaCl; while the cells grown in 2M NaCl showed high oxygen absorption under 2M NaCl.

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With the purpose to utilize the soybean cooking drain from miso factories, cultivation of molds was investigated employing 66 strains including Aspergillus, Monascus, Penicillium and Paecilomyces. Aspergillus oryzae FRI-23 gave the best results with respect to cell yield and enzyme activity in the mycelia. Good growth of the mold was obtained by starting the cultivation in the medium at pH 6, and addition of carbon source such as glucose was more effective than addition of nitrogen source such as ammonium sulphate. The mass doubling time and the specific growth rate were determined 3.5hr and 0.2hr^-1, respectively. AS the result of cultivation, COD of the soybean cooking drain was reduced to the level of 15% of the initial concentration (20, 000ppm). Higher enzymatic activities of acid proteinase (pH 3), neutral proteinase (pH 6 and 7.5) and peptidase in mycelia were seen at logarismic phase of the growth. Crude protein and nucleic acids contents of the dried mycelia were approximately 40% and 4%, respectively. As the result of the addition of the cultivated raw mycelia to miso as the source of protein and enzymes for acceleration of the fermentation, the amounts of free glutamate and flavor of the miso increased during fermentation of the miso.

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Substrate specificity in biosynthesis of volatile esters in strawberry fruit was investigated. Various aliphatic alcohols and volatile fatty acids as substrates were incubated with a whole strawberry fruit in a flask at 30°C for 90min, and then the headspace volatile was analyzed by gas chromatography. Primary and secondary aliphatic alcohols, straight-chain, branched, saturated or unsaturated, were found to be esterified, whereas tertiary alcohols were not utilized as substrate. Not only acids in strawberry such as acetic, n-butyric and n-caproic acids but also other acids including isovaleric, n-valeric and isocaproic acids were esterified when each of them was incubated with the fruit. Formic acid, however, was not esterified. As for propionic and isobutyric acids, apparent results were not obtained because of the low conversion rate and the poor reproducibility. A clear correlation was observed between substrate specificity and volatile esters present in a strawberry fruit.

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The components of fouling materials of mandarin orange juice on the membrane during Reverse Osmosis (RO) concentration were analyzed by washing the deposit from the membrane. Fouling components were mainly pectin, and insoluble materials similar to cellulose. The relatively low molecular weight components, sugars and amino acids, were in lower concentrations in the deposit than in the feed solution. A model solution consisting of the major components of the deposit, pectin and cellulose, was used for examination of the increasing rate of the resistance to water permeability by the deposit. There was no declining flux in the suspension of cellulose. However, a large decline of flux was demonstrated with the solution of pectin. This decline depended on the permeability of the membrane and the operating conditions. A little decline in rate resulted after insolubilization of pectin with calcium chloride. Therefore, it was demonstrated that pectin is a dominant component for resistance, and the increasing rate of resistance to the permeability of water by deposits was governed by the flow velocity in the range of flow rates used in this study. Fractionation by molecular weight of the components of pectin deposited on the membrane was carried out by a gel-filtration technique with a Sepharose 4B column. Pectin has a broad molecular weight range and high molecular weight pectins deposited on the membrane during RO treatment was found to be very large. This phenomenon shows that the higher molecular weight substances have lower diffusibility and lower molecular weight substances have higher diffusibility.

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