In oder to prepare odor reference solutions for principal odor attributes of foods, two response pattern matrices were constructed between 15 odor attributes and 43 odor-descriptive terms on the basis of images of the odor attributes and sensory evaluation of the odor preparations, respectively. The modification of the preparations, their sensory evaluation and multivariate analysis (Quantification theory 2, cluster analysis and Quantification theory 3) of the response pattern matrices obtained were repeated till two response patterns of each odor attribute coincided with each other.

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For the enzymatic production of peptide mixture from milk casein, 15 kinds of proteases from different sources were estimated based on bitter taste and molecular weight distribution of hydrolysate preparations. Through this screening, 3 kinds of proteases (Protease-B, Protease-3545 and Protease-4454) were selected, and then, proteolytic characteristics of these enzymes and the properties of the hydrolysates were investigated. The results obtained were summarized as follows: (1) Protease-3545 and 4454 were more effective than Protease-B in terms of the proteolytic activity based on peptide concentration and average peptide length (APL) of the hydrolysates. It was presumed that these properties were due to the presence of high peptidase activity in these enzyme preparations. (2) APL of the hydrolysates could be estimated from the analytical value obtained from a peptide analyser. (3) The hydrolysate preparation having APL less than 2 possessed an acceptable level of bitterness. (4) It was recognized that Protease-3545 released proline, glutamic acid, alanine and tryptophane, on the other hand, Protease-4454 released phenylalanine, asparagine, isoluecine, arginine and threonine selectively. (5) From these results, it was concluded that Protease3545 was most suitable enzyme to prepare peptide mixtures having no bitter taste.

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The rate of hydrolysis of lactose by β-galactosidase, immobilized into cellulose triacetate fibers, was studied using a horizontal rotary column reactor. The rotary column reactor, developed by us, consists of wire-mesh cylinder, separated into four chambers by punched plates. A feed shaft, with many orifices, runs down the center of the cylinder. This shaft is covered with wire mesh. After placing the immobilized β-galactosidase in the chambers, lactose solution was fed from a tank to the cylinder through the orifices and wire mesh, to contact the immobilized β-galactosidase. The results were as follows. (1) The rotary column reactor could be operated without a channeling or a severe pressure drop through the column that was observed in a packed bed rector. (2) The reaction rate in the rotary column reactor could be increased suddenly by increasing the rotational speed from 11 to 21rpm and increased gently by increasing the rotational speed from 21 to 47rpm at a lactose solution concentration above 4% (w/w). (3) The reaction rate in the rotary column reactor at 21rpm was 1.16 times of the reaction rate in a packed bed reactor at 75.1ml/s. Thus, the rotary column reactor has a higher reaction efficiency than a packed bed reactor. This may be because the contact efficiency between the lactose and cellulose triacetate fibers, which support the β-galactosidase, is improved by the rotation of the column. (4) The rate of lactose transfer into the immobilized β-galactosidase in the rotary column reactor was improved by increasing the rotational speed. The reason was considered, as follows, by discussion of the JD-factor. The fibers become highly dispersed in the lactose solution as the rotational speed increases, increasing the effective specific area for lactose transfer. (5) From an orthogonal experiment, L₈, it was found that the reaction rate is affected greatly by the packed density of immobilized β-galactosidase.

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The viscous properties of the water extracts from buckwheat flour were investigated using a B-type viscometer. The viscosity of the extract solutions depended upon shear rate, and exhibited pseudoplasticity. And it decreased as ionic strength increased. The viscosity of supernatants prepared from the extract solution at different pHs provided a minimum value at pH 3.0-3.4. The viscosity of the supernatants prepared at different temperatures under 90°C was constant. It was revealed from measurements under some denaturation conditions that the viscosity of the supernatant corresponded to the content of total carbohydrate rather than that of protein. The water extract was fractionated by ion exchange chromatography on a DEAE-Shephadex column. One fraction of them was given higher viscosity over 18 times than that of the other fractions. The high viscous fraction was mainly composed of sugar. Composition of the sugar was galactose, xylose and mannose in the decreasing order of contents. On the basis of these results, it was concluded that the viscosity of the water extracts from buckwheat flour was attributable to polysaccharides.

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Microorganisms which degrade citrus processing wastes were screened. Screening was designed to obtain strains which degrade the waste effectively, so that the residue can be easily dehydrated and its volume and weight reduced. Two hundred and forty three strains were isolated on a medium consisting of citrus peel, oolong tea and coffee extracted wastes. Two species each of yeast and mold were characterized. They were identified as Hansenula sp. (Y-2), Candida sp. (Y-11), Byssochlamys sp. (M-9) and Aspergillus sp. (M-21). The optimum temperature for growth was 40, 35, 45 and 40°C, respectively. The optimum pH was approximately 6.0. These organisms grew better on glucose, fructose, maltose and sucrose than on other carbon sources tested. Yeast extract was the most effective nutrient for the growth of these organisms.

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Citrus peels supplemented with rice bran and several nutrients were degraded on a laboratory scale by four species of isolated organisms, Hansenula sp. Y-2, Candida sp. Y-11, Byssochlamys sp. M-9 and Aspergillus sp. M-21. The peel mixture was incubated at pH 6.0, 40°C for 5 days. Byssochlamys sp. M-9 was the most effective organism for reducing the weight and volume of the peel, which reducing rate was 54.3% and 29.6%, respectively. During 5 days incubation, the cell masses of Byssochlamys sp. M-9 and Aspergillus sp. M-21 increased during the first 4 days. However, the cell numbers of Hansenula sp. Y-2 and Candida sp. Y-11 increased during the first 2 days and remained relatively constant thereafter. Hesperidin, one of the useful citrus constituents, remained constant throughout the degradation process. Therefore it was suggested that hesperidin wae extracted more effectively from the degraded product than from the untreated peels.

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Effect of moisture-sorption on gelation of a commercially available soy protein isolate (SPI) was investigated. After the SPI was dispersed in water, the protein sample was lyophilized and stood for 1 day at 100% of relative humidity and 50°C. Hardness and cohesiveness of a gel obtained from the SPI sample by heating at 90°C for 30min in 0.01M Tris-HCl buffer (pH 8.0) after moisture-sorption were increased by 12% and 32 %, respectively, compared with those of the gel obtained only by heating (heated gel). When the buffer containing 0.5M NaCl was used, the hardness was increased by about 6 times and the cohesiveness decreased to approximately 80% of those of the moistureinduced gel obtained in the absence of NaCl. However, it was observed that both texture parameters were higher by 22% (hardness) and 51% (cohesiveness), respectively, than those of the heated gel.

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Hard gel like pectin-gel was easily obtained from the surface of Aigyokushi (Ficus pumila L. var. awkeotsang Corner) seeds by stirring and extracting with distilled water for 15-20 minutes at room temperature. The hardness of the gel decreased during storage of 4°C. The strength of the gel increased by an addition of alkaline earth metals. The Aigyokushi gel was found to be an effective carrier for immobilized enzyme. Activity of immobilized papain was maintained at high levels and was very stable after repeated runs.

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An improved method was developed for production of rice vinegar from uncooked rice-bran by a parallel-combined process consisting of enzymatic saccharification, ethanol fermentation with acetic acid tolerant yeast and acetic acid fermentation with acetic acid bacteria. An acid stable glucoamylase from Rhizopus sp. which is able to produce glucose enzymatically from raw starch in the presence of acetic acid was chosen for the purpose. In addition to a common acetic acid bacteria, Saccharomycodes ludwigii which demonstrates a normal ability of ethanol fermentation in 1% acetic acid was selected as an acetic acid tolerant yeast. In the actual process of rice vinegar fermentation, these three independent steps were allowed to act at a time in one mash batch containing 12-14% (w/v) of uncooked rice-bran, and incubation was carried out as static culture through the processs. As a result, the newly developed method was evaluated to be superior to classic conventional methods on the acetic acid yield.

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Water was flowed through the packed bed of ceramic spheres containing crystallites of polar crystal tourmaline and surface tension and permeability was measured. The surface tension of treated water considerably decreased as compared with the control. However, the surface tension of treated water increased after the treatment and approached to that of the control after about 1 hour and a half in distilled water and after over 3 hours in city water. The permeability of water also increased after treatment and decreasd as same as the behavior of surface tension.

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Sorption behavior of volatile compounds by high gas barrier films was investigated in aqueous solution after storage for 2 months, comparing with that by middle-density polyethylene (MDPE) film. With amorphous nylon, distribution ratios (quantity of a compound recovered from a film/quantity from sample solution) were less than 0.026 and were little affected by functional groups of the volatile compounds. The ratios for hydrocarbons were less than 1/34 in comparison with those of MDPE. On the other hand, thermoplastic polyester had higher affinity for esters than MDPE, especially for alkyl benzoates, and the distribution ratios were 1.7-9.1 times.

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Determination of some sulfur-containing components and free amino acids in various strains of garlic (13 purchased and 11 cultured specimens) was carried out by various HPLC analyses. Alliin was the most abundant sulfur compound and was followed by cycloalliin, whose content was comparable to that of S-methyl cysteine sulfoxide. Among free amino acids Arg is the most abundant and its content was comparable to that of alliin. The distribution of cycloalliin in the leaf and the bulb with growth of garlic were different from that of alliin.

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Effect of dietary miso on the activities of various hepatic enzymes in lipid biosynthesis and degradation was examined in rats fed a cholesterol-free diet for 18 days. The inclusion of 20% desalted miso to the experimental diet significantly decreased the concentration of serum cholesterol and doubled the fecal excretion of acidic steroids without influencing that of neutral steroids. The dietary miso greatly increased the activities of the rate-limiting enzymes in cholesterol biosynthesis and degradation in liver microsomes. In contrast, dietary miso was ineffective in modulating activities of enzymes in fatty acid oxidation and glycerolipid synthesis. Microsomal lipid contents and compositions were uninfluenced by dietary miso. It was suggested that the miso contained the component (s) which specifically increase the facal excretion of bile acids. The enhanced bile acid excretion may be compensated by the increase in the catabolism of cholesterol to bile acids and reduce the serum cholesterol concentration as observed in the present study.

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Ripening of banana was accelerated by 2-3 days with application of 60% ethanol (10ml/12 fruits). However, 1000ppm ethylene induced more rapid ripening changes: in peel color, sugars and organic acid contents. Sucrose, glucose and fructose were identified by high performance liquid chromatography (HPLC). All the three sugars increased with ripening and sucrose was predominant at all stages of ripeness. The increase in sucrose preceded that of glucose and fructose and the ratio of glucose-frucose was almost constant during the course of ripening, that is, from initial (green) until 9 or 14 days of storage. Malic and citric acids were present in almost equal amounts in green fruits (initial). Malic acid increased 2 to 3.6 times the initial level, becoming the predominant acid in ripe fruits. Citric acid increased only in overripe and senescent fruits.

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