To investigate the sensory attributes of wild rice, a sensory evaluation of the wild rice was conducted using a semantic differential (SD) method for comparing Hatomugi (Job's tears), brown rice, and polished rice. Through a factor analysis (principal factor method), the following five factors were extracted: the first factor was overall image and mouth-feel, the second factor was appearance, the third factor was texture, the fourth factor was flavor, and the fifth factor was after-taste and/or peculiarity of taste. From the profile that was constructed to differentiate between the sensory attributes of wild rice and those of the other samples, the following trends can be recognized; in contrast with Job's tears the wild rice was found to be longer, more delicate, smoother in mouthfeel, delicious and full-bodied, and dark brown in color. The wild rice also excelled in after-taste. In comparing brown rice with wild rice, the wild rice was softer and had little of the stiffness of brown rice. In polished rice versus wild rice, the wild rice bore more the connotation of a health food and frugal meal, while rough in mouth-feel and also lack stickness.

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The baking quality of some bread flours which were milled from the domestic and the imported foreign wheats was studied in terms of the characterization of the isolated starch, of the dough, and of the baked bread. (1) On the property of starch isolated from each wheat flour, it was obvious that the swelling power and Solubility of domestic wheat starch was considerably high although the general analysis data did not give any appreciable differences. (2) From the small scale experiment on the dough making according to the AACC method [Amer. Assoc.Cereal Chem. Approved Method: 10 (1969)], the more the amounts of yeast were added, the more the carbon dioxide gas generated from a dough made from domestic wheat flour. The gas production was maximized at 120min after dough making and the gas retention decreased gradually thereafter. (3) From the compraison of two different methods of dough making, streight-dough and no time-dough, the loaf volume of the bread baked by the no time-dough method gave an excellent result. Although some difficulties still remain in the bread quality, tenderness or crumb firming, considerable improvement was attained by increasing the amounts of shortenings added and by modifying the interaction between shortenings, starch and gluten so as to protecting the gas leakage.

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The clarification of Satsuma mandarin (Citrus unshiu Marc.) juice by ultrafiltration was investigated by the use of DDS plate-and-flame module with three kinds of membranes, GR 51 PP, GR 61 PP and GR 81 PP (molecular weight cut-off of 50000, 20000 and 6000, respectively). (1) The effects of process parameters on the permeation flux were studied. The permeation flux increased with an increase in flow rate or temperature. The higher operating pressure gave a higher permeation flux in GR 81 PP, however, the increase of pressure gave the decrease of permeation flux in GR 51 PP and GR 61 PP. (2) Permeation flux of the membranes was mostly restored by cleaning with warm alkaline detergent solution after treatment. (3) In ultrafiltration of 10° Bx, 20° Bx and 30° Bx juices by a batch operation, the amount of soluble solid permeated through the membranes was larger in 30° Bx juice than that in 10° Bx or 20° Bx juices. The permeation of juice components such as soluble solid, acid, amino-nitrogen and vitamin C were partially rejected. Pectin was scarcely detected in permeates. (4) A higher permeation flux was observed in Satsuma mandrin juice treated with suitable concentration of a pectic enzyme before ultrafiltration. (5) The compositions of Satsuma mandarin juice and lemon juice clarified by ultrafiltration was almost the same as those by conventional enzymatic treatment and celite filtration, but the colour and flavour was a little better in ultrafiltrated juice.

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The estimation of bacterial counts in raw milk was studied using Direct Epifluorescent Fitler Technique (DEFT). The milk inoculated with Bacillus cereus was detected 10³ to 10⁷ counts/ml using DEFT. In the case of raw milk, the regression line was log(DEFT)=0.86log(SPC)+0.91; r=0.81, and 10⁵ to 10^6.5 counts/ml were detected. Application of DEFT to the sterilizing effect of LTLT (low temperature long time) pasteurized milk and to the post pasteurization contamination of UHT (ultra high temperature) sterilized milk may be useful. The differential determination of sublethal injured bacterial cells was tested by DEFT. The RNA (ribonucleic acid) of viable cells was stained orange by acridine orange, but inactive cells and DNA (deoxyribonucleic acid) were stained green. When sublethal injured cells were prepared by heat treatment, the ratio (injured cells/unharmed cells, green cells/orange cells) were as follows: Enterobacter cloacae: (1.89, 1.36), (14.71, 19.75), Bacillus cereus (vegetative form): (1.18, 0.88), (2.71, 2.06), and Staphylococcus aureus: (0.92, 0.90), (0.50, 0.40), but with poor agreement for Candida krusei. Acid producing activity and acridine orange-staining characteristics of lactic starter culture (Lactobacillus bulgaricus, Streptococcus thermophilus) and its concentrates (L. acidophilus) were determined. There was a high correlation between acid production and staining characteristics.

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Eight strains of yeast, Candida tropicalis WH 4-2, Candida lipolytica No. 6-20, Candida lipolytica IAM 4974, Candida rugosa JF 101, Candida rugosa JF 114, Cryptococcus albidus IAM 4317, Trichosporon sericeum EP 4-3 and Trichosporon sp. EP 4-8, were grown on media containing pig bone fat as a sole carbon source in shaking culture. Total lipid contents of cells differed among the strains tested, and also the fatty acid compositions of those lipids differed in each strain. But, it was considered that the fatty acid profiles of those lipids were fairly reflected by the fatty acid composition of bone fat used as substrate. C. tropicalis WH 4-2 and Trichosporon sp. EP 4-8 were incubated on pig bone fat at different starting pH values of media using Jar fermenter on agitating and aerating conditions. C. tropicalis grew more rapidly at starting pH 6.2 than at pH 7.2, and also, Trichosporon sp. grew more rapidly at starting pH 6.3 than at pH 7.1 on bone fat media. Maximum cell yield was attained in the culture at starting pH 7.2 than pH 6.2 in case of C. tropicalis, whereas the cell yield did not significantly differ on different starting pH of media in case of Tricosporon sp. Lipid class fractions from cellular lipids of C. tropicalis and of Trichosporon sp. were studied on relation with starting pH of media, and no remarkable differences resulted from starting pH were observed in the fatty acid compositions of respective lipid fractions of both yeast strains. Essentially similar amino acid compositions were observed on the both yeasts grown on bone fat at different starting pH of media, and it was considered that those yeast cell proteins have comparatively well-balanced amino acid profiles on nutritive viewpoint.

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Rapid extraction and colorimetric detection as well as determitnaion method of BHA (butyl hydroxyanisol) in foods was developed used by binding reaction with 2, 6-dichloroquinonechloroimide. BHA extracted from sample with n-hexane was selectively transferred into aqueous layer by shaking with ethanol-borate buffer (1+1) mixture containing 2, 6-dichloroquinonechloroimide. 2, 6-Dichloroquinonechloroimide was used as chelating agent in order to separate BHA from lipid. If BHA was contained in sample, the color of aqueous layer changed to blue clearly (qualitatively). Then the BHA chromogen was reextracted into butyl acetate layer, and determined by colorimetry (quantitatively). The recoveries of BHA from samples fortified at 20 and 200ppm was more than 78.1% and 86.0%, respectively. Detection limit of BHA in sample was 1ppm by the proposed method. The recoveries were superior to those of partition or distillation method.

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L-Glutamic acid, sodium ion (Na⁺) and chlorine ion (Cl^-) of 26 varieties of commercial powdered soup and 4 varieties of soup were determined. L-Glutamic acid was determined by the method with glutamate dehydrogenase. Na⁺and Cl^- were determined by ion meter. The detection limit of the method for L-glutamic acid, Na⁺ and Cl^- were 2ppm, 2.3ppm and 35.5ppm, respectively. The recoveries of L-Glutamic acid, Na⁺ and Cl^- added to commercial powdered soup were in the range of 97.9-100.5%, 94.5-105.6% and 101.1-107.5%, respectively. L-Glutamic acid contents were 1.2-15.6% in instant "miso shiru", powdered soup and instant "chazuke" and 0.3-0.6% in soup for chinese noodle. Na⁺ contents were 5.3-27.4% in instant "miso shiru", powdered soup and instant "chazuke" and 0.5% in soup for chinese noodle. Cl^- contents were 10.0-41.3% in instant "miso shiru", powdered soup and instant "chazuke" and 0.8-0.9% in soup for chinese noodle.

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Special, first and second grade chinese fish sauce were examined in quality in terms of chemical composition, free amino acid etc. The results were as follow: (1) Sodium chloride content and pH value were similar in every sample but there were significant differences in other other chemical composition. (2) Free amino acid content was higher in the first grade and less in the special grade fish sauce. In special grade sauce, leucine, alanine and glutamic acid predominated. In the first and second grade sauce, glutamic acid predominated, followed by lysine and alanine. (3) The correlation was not recognized between the sauce grade and chemical composition, free amino acid content or sensory score.

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Enzymatically modified gelatin (EMG) prepared by covalent attachment of L-leucine n-dodecyl ester was used as a conditioner for protein-frotified breads. Soy protein isolate (SPI) and fish protein concentrate (FPC) were selected as fortifiers and each was used at 5 and 10% of wheat flour. The use of these fortifiers gave breads with decreased loaf volume, firmed crumb and coarse grain. EMG used at 0.8% of flour mitigated these adverse effects, producing better quality bread than monostearin (MS) did. EMG exerted its function sufficiently, particularly when used in combination with vital gluten which substituted a 5% portion of wheat flour.

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Simultaneous quantitative determination of allyl isothiocyanate and β-phenethyl isothiocyanate by gas chromatography equipped with FPD was investigated. Column was packed with 5% PEG 20M/Chamelite CS. Internal standards used were thionaphthene and phenyl isothiocyanate, and n-hexane was used as a solvent. Relations of both y=ax+b and y=cx^d were recognized between the concentration of allyl isothiocyanate (x) or β-phenethyl isothiocyanate (x) and ratio of peak area of allyl isothiocyanate or β-phenethyl isothiocyanate vs. that of an internal standard (y). Values of a, b, c and d are constant in equations. Contents of each isothiocyanate in n-hexane extract of horseradish flour hydrolysate were determined using above both equations, and were nearly equal. Values calculated with thionaphthene as standard were nearly equal to those with phenyl isothiocyanate as well.

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