The growth inhibitory action of acetic acid and the protective effect of a liverextract onits inhibition against Debaryomyces hansenii were investigated to estimate the antimicrobialmechanism of acetic acid.(1) In a casamino acid yeast extract medium containing aceticacid (pH 5.0), the growth of yeast was inhibited with an increase of acid concentration, andbactericidal effect was recognized above 3.0% of acetic acid.(2) In the casaminacid yeastextract medium, the growth of resting cell treated in phosphate buffer solution (pH 5.0)which contained less than 4.0% of acetic acid for 3h at 30°C was the same level as that ofnontreated case.(3) The liver extract stimulated the growth of yeast in the casamino acidmino acidinhibitionby acetic acid in the same medium containing 1-4% of acetic acid. Moreover, theliverextract exhibited not only relief action on growth inhibition by acetic acid, but also recoveryaction from acid inhibition. (4) The protective substance for acetic acid inhibition which iscontained in the liver extract was estimated to be a compound that exhibit maximumabsorption near 260nm and comparatively low molecular weight.

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Similarities among 51 abstract terms for odor-description were evaluated by trained panelists and untrained ones. The similarity matrix was analyzed by non-parametric multi-dimensional scaling (quantification theory 4) and cluster analysis was done on the scores from the first to tenth axis obtained by quantification theory 4. (1) The clustering of the terms reflected their skill of the trained panelists, who were the research workers of Ajinomoto Co., Inc., the food flavorists of Ogawa Co., Ltd. and the graduate students of a laboratory of food analysis. (2) The terms were separated to 9 clusters and 8 isolated terms on the basis of value and volatility by analyzing the sum of the three data sets. (3) With comparing the results of trained and untrained panelists, 42 terms were classified into the same odor groups.

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Similarities among 54 concrete terms for odor-description were evaluated by trained panelists and untrained ones. The similarity matrix was analyzed by non-parametric multi-dimensional scaling (quantification theory 4) and cluster analysis was done on the scores from the first to tenth axis obtained by quantification theory 4. (1) The terms were separated to 16 clusters and 4 isolated terms by analyzing the sum of the three data sets obtained by the research workers of Ajinomoto Co., Inc., the food flavorists of Ogawa Co., Ltd and the graduate students of a laboratory of food analysis. (2) Only 35 of the concrete terms were separated into the same odor groups from the results of trained and untrained panelists. (3) As the odor-descriptive terms of food products, 44 terms were chosen.

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In order to characterize odor-descriptive terms, a response pattern matrix was made with 44 terms and 53 kinds of foods by evaluating the odors of foods. The matrix was analyzed by quantification theory 3 and cluster analysis was done on the scores from the first to fifth axis obtained by quantification 3. (1) The terms were separated into 12 groups on the basis of their odor images by analyzing the sum of the three data sets obtained by the research workers of Ajinomoto Co., Inc., the food flavorists of Ogawa Co., Ltd. and the graduate students of a laboratory of food analysis. (2) In the result of untrained panelipanelists, the difference between the odor image of"value"and"activity"was indistinguishable. (3) With comparing the results of trained and untrained panelists, 35 of the terms were classified into the same odor groups.

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Peel oils of yuzu (Citrus junos Tanaka) were extracted by supercritical carbon d ioxide (SCCO₂) from peel residues of juice extraction or raw peels. The characteristics of oils were compared with those of cold-pressed or solvent-extracted oils. A pilot plant for SCCO₂ was operated at 15°C under 100kg/cm² in an extractor (4l) and at 30°C under 40kg/cm² in a separator (2l). 1) The yield of peel oils from crushed yuzu peel residues by SCCO₂extraction was 1.2%, while the yield from raw peels without crush was as much as 3.9%. 2) The physical constant values of refractive index and specific gravity were simil ar in each oils, but specific rotation was different between SCCO₂-extracted oils and other oils. 3) Mono and sesquiterpenes in addition to higher-boiling point components containing linaloo β-farnesene, bicycloelemene and thymol were extracted highly by SCCO₂ as compared with cold-pressed or solvent-extraction.

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In this study we discussed the effects of external factors on the sorption of ethyl hexanoate into polyethylene (PE) film. The effects of the type, concentration and HLB (Hydrophile-Lipophile-Balance) value of surfactants and pH of their solutions on the sorption were examined. In SDS solution, the solubility coefficient of ethyl hexanoate was unchanged below the CMC (Critical-Micelle-Concentration, 0.25%), but dramatically decreased above the CMC. Especially in 1.0% SDS solution, the coefficient decreased by about 90% as well as its volatility. On the other hand, in Sugar-Ester (CMC, 0.025%) and food emlsifier (CMC, 0.05%) solutions the solubility coefficient was independent of the concentration of the surfactants, although the volatility decreased. The HLB value of Sugar-Esters and the pH of flavor solutions had no influence on the sorption of the flavor compound into PE film.

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The change of form of phenolic compounds during storage was investigated and the relation to chilling injury was discussed. Three phenolic fractions of free (I), esterified (II) and insoluble-bound (III) forms were extracted from water convolvulus stored at 1°C and 20°C, and the changes of total phenol and o-diphenol contents in each of the fractions were examined. At harvest, total phenol and o-diphenol were found most abundantly in fraction II. During the storage at 20°C, the contents were almost constant or showed a little increase in every fraction. At°C, however, they showed a marked and a little increases in fraction and III, respectively, and a decrease in fraction II. The ratio of each fractions to total of three fractions showed a little change at 20°C. At 1°C, on the contrary, a marke d increase of fraction I and a marked decrease of fraction II were observed, suggesting transf ormation of phenolic com pounds from a relatively stable form into areactive one. The ratio of fraction III was low throughout the storage period at both temperatures. As phenolic acids, caffeic acid in fraction I, chlorogenic and caffeic acids in fraction II, were dominant. In fraction III, ferulic acid was only detected.

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A new method for measuring the solubility (sorption) [μg·cm^-3/ppm], diffusion [cmcm²/sec] and permeation coeffcients [μg·sec^-1·cm^-1/ppm] of volatile compounds in aqueous solutions into polyethylene (PE) film was established. The amount of a volatile compound permeating the PE film was detected by use of a flame ionization detector (FID) of gas chromatograph and a differential permeation curve was obtained. The diffusion and permeation coeffcients increased with increasing the concentration of the volatile compound, while the solubility coeffcient was unchanged. In the case of nethyl esters, the solubility coefficient increased about three-fold for each methylene group, but the increment was less in the esters composed of 10 or more carbon atoms.

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Estimation of gelatinization, retrogradtion and destruction of mochi (glutinous ricecakes) for Arare was studied by using uncooked glutinous milled rice; steamed glutinous rice; fresh mochi; and cooled retrogradated mochi. (1) Use of a 0.04% sodium lauryl sulfate solution for dispersion medium permitted the determination of the degree of dispersion to correspond to the degree of gelatinization evaluated by the β-amylase-pullulanase method. (2) It was found that degree of dispersion of retrograded starch increased with an increase of the dispersion temperature from 30°C to 52.5°C, and that of gelatinized and swelled starch decreased with a decrease in concentration of 1.0% to 0.1% (3) The degree of gelatinizasion of mochi could be estimated by the degree of dispersion at 1.0% concentration at 30°C. The degree of gelatinization of mochi at α stage could be estimated by the degree of dispersion at 1.0% concentration at 52.5°C. The degree of retrogradation of mochi in strongly bonding micelles could be estimated by the differrence of the degree of dispersion at 1.0% concentration at 52.5°C and that at 1.0% concentration at 45°C. The degree of destruction of mochi could be estimated by the degree of dispersion of a O.1% filtrate of its supernatant at 52.5°C.

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The effects of adipic acid on the preservation of the starchy foods in which aeobic sporeforming bacteria were the most dominant putrefying flora were studied. (1) Cooked rice: Two to six mg of undissociated adipic acid in 100g of cooked rice inhibited the growth of Bacillus subtilis as below 10⁷/g for 5 days at 30°C. The storage life of cooked rice which was in 0.15% of adipic acid solution containing 6.5mg of undissociated molecules per 100g was estimated at 5 days. (2) Boiled noodles: The growth of B. subtilis in the boiled noodles was completely inhibited with addition of 0.25% of adipic acid, pH 5.15 or 23.5mg ofundissociated molecules of adipic acid to 100g of boiled noodles for 3 days at 30°C. On the basis of the concentration of undissociated molecule, it was estimated that the effective adipic acid concentration for preservation of boiled noodles was 0.14 and 0.70%, respectively, at pH 5.0 and 5.5. Although the pH of boiled noodles containing 0.25% of adipic acid was rather higher than those of boiled noodles containing 0.25% of DL-malic or citric acid, the antibacterial effect of adipic acid was superior to then. (3) Neri-an: The growth of B. subtilis in the neri-an was completely inhibited with addition of 0.2% of adipic acid, pH 5.25 and 13.8mg of undissociated molecules of adipic acid to 100g of neri-an for 7 days at 30°C. On the basis of the concentration of undissociated molecule, it was estimated that the effective adipic acid concentration for preservation of neri-an was 0.1 and 0.48%, respectively, at pH 5.0 and 5.5

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The dried skipjack has widely been used from olden times in Japan to prepare sto ck. A principal taste-active component was already identified as IMP, but the contribu tion of other components to its characteristic taste is still obscure. In order to identify the taste-active components by the omission test using a synthetic extract, the hot-water extract of dried skipjack was first analyzed for free and combined amino acids, nucleotides and related compounds, other nitrogenous compounds, organic acids, sugars and inorganic ions. Large amounts of histidine and anserine were detected and the sum of both components reached about 86% of the sum of free amino acids and imidazole dipeptides. After acid hy drolysis of the extract, the content of free amino acids increased remarkably, indicating the occurrence of a considerable amount of oligopeptides. The levels of IMP, creatine and creatinine were also very high. More than 98% of the extractive nitrogen was accounted for by these nitrogenous constituents. Lactic acid was predominant among the detected organic acids, while sugar components were fairly low in amount. As for inorganic ions, Cl<^-, K<⁺, PO₄ ^3-and Na⁺ were major components.

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