The utilization of soya lactic acid bacteria (Pediococcus halophilus) was investigated to improve the quality and color of Shiro-shoyu (extremely light colored soy sauce). The color-lightening strains lowered the oxidation-reduction potentials of Shiro-shoyu moromijuice (MJ) medium during their growth and suppressed the browning of the medium. A color-lightening strain C-6-8 grew vigorously (viable cell of 10⁸ per ml) in the Shiro-shoyu MJ medium. In the incubation at 21-30°C, the growth of strain C-6-8 slowed down with lowering temperature, while at the lower temperature the period of fermentation were longer than that at the higher temperature. In Shiro-shoyu moromi (mash) inoculated with strain C-6-8, lactic acid fermentation was continued about two weeks at 22°C, and darkening phenomenon of moromi was suppressed during the fermentation. The contents of total nitrogen and L-glutamic acid of Shiro-shoyu made by inoculation of strain C-6-8 were slightly lower than that of non inoculated. However, production of a large quantity of lactic acid and acetic acid resulted low pH and high buffer action. These results suggested that the inoculation of soya lactic acid bacteria to Shiro-shoyu moromi were useful to improve the taste and color of Shiro-shoyu.

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To measure the difference in aroma quality among five domestic navel oranges which are very closely related species, the odor quality of volatiles in peel oil was studied by organoleptic methods and statistics.
Each oil isolated from the peels of five kinds of navel oranges, such as Washington, Fukumotobeni, Ohmishima, Shiroyanagi and Morita, was separated into hydrocarbon and oxygenated fractions through a silica gel column. The aroma quality of each fraction of oxygenated compounds having a characteristic aroma was determined by sensory evaluation, GC pattern similarity and odor unit values. The GC pattern similarity between Ohmishima and Morita was 0.963, and Shiroyanagi and Washington 0.951. The aroma quality of Fukumotobeni differed from those of the other four navels. Odor unit values (Uo) calculated from each concentration and odor threshold were applied to this investigation. The ranking by exponential Uo was clearly useful to pinpoint the contributive components for the aroma quality.

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The change of antioxidative activity of extracts of Katuobushi during smoking process was investigated. The antioxidative subsutances in the extracts was examined. Results obtained were as follows: (1) The antioxidative activity of the extracts gradually increased and reached maximum in the half period of smoking process. (2) The extracts of Arabusi (Skipjack meat after smoking process) was fractionated by dialysis. The antioxidative activity was mainly recoginized in the dialyzable fraction. The dialyzable fraction was fractionated on ODSmini-column (YMC-DispoC18, Yamamura Co. Ltd) by eluting with mixtures of water-acetonitorile, increasing the ratio of acetonitorile in steps. The fractionation of antioxidative substances eluted with water was applied to HPLC. A number of peaks which appeared in the chromatogram of extracts of Arabushi compared with that of Namaribushi (Skipjack meat is boiled and smoked once for about an hour were seemed to be responsible for antioxidative reinforcement of extracts of Katuobushi. The main antioxidant peak which remarkably increased during smoking gave serine, proline, glycine, aranine and isoleucine after complete hydrolysis. (3) The extracts of Katuobushi showed an antioxidative activity against a minced sardine.

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Low molecular weight carbohydrates have been preparatively isolated from the soybean oligosaccharide syrup by high performance liquid chromatography using two column systems. Ten carbohydrates including six galacto-oligosaccharides and one cyclitol were clearly identified by ¹³C-NMR (500MHz). Composition of carbohydrates was estimated by comparing peak area of the HPLC peaks: stachyose (21.9%), raffinose (5.8%), manninotriose (5.4%), melibiose (1.1%), galactopinitol A (2.6%), galactopinitol B (2.4%), sucrose (34.6%), glucose (7.2%), fructose (8.3%) and pinitol (5.5%). The content of the growth activator of bifidobacteria (stachyose, raffinose, manninotriose and melibiose) was about 34%.

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Cooking rates of polished rice in a pressure pot were measured at high temperatures from 110 to 133°C. The cooking rate was evaluated from the gelatinization degree of rice starch measured with a enzyme method. The Arrhenius plots of cooking rate constant showed a good linear elationship, and the activation energy was 38.1kJ/mol. The cooking times for isothermal cooking process of polished rice at 110, 120, and 30°C were estimated at about 11, 8, and 6min, respectively.

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A liquid part of fermented Kabuzuke was used as seasoning liquid of fresh turnips. The quantity of main organic acids of turnips pickled in this clear liquid for 48 hours at 4°C was almost the same of fermented turnips. The leaf color of the pickled turnips appeared to be more freshgreen than that of fermented turnips. Colonies of several kinds of bacteria decreased in order from 10⁷-10⁴ cells/ml to below 1010²/ml after 72 hours. When stored at 25°C, turbidity of this clear liqulid increased with in short period, but at 4°C, did not increase for a month. In conclusion, this liquid part may be useful as a seasoning liquid of pickle.

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Acerola juice contains a high concentration of ascorbic acid (AA). The juice to which ethanol was added was fermented by Acetobacter aceti IFO 3283 to produce acerola vinegar. Submerged and static fermentation was employed for acetic acid production, and changes in AA and dehydroascorbic acid (DHA) were investigated during fermentation. In the submerged fermentation the amount of AA decreased but that of DHA increased, while in the static one the amounts of AA and DHA decreased as the fermentation proceeded. From the viewpoint of the total vitamin C (AA plus DHA) content of the product, the submerged fermentation was superior to the static one. Acerola vinegar produced by the submerged fermentaion was stored under various conditions. The amount of AA of the vinegar stored at room temperature decreased faster than that stored at 4°C and light exposure accelerated the decrease, indicating that AA of the vinegar was labile to heat and light.

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Phospholipids consist of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were synthesized by use of an industrial pancreatic phospholipase A₂. Lysophosphatidylcholine (LPC) isolated from a commercial emulsifier, mixed fatty acids obtained from sardine oil, the concentrated sardine oil (EPA+DHA>60%), and 99.4% EPA were used as substrates. Optimum water content was found to 13.4%/system, and optimum ratio of LPC to mixed free fatty acids was 11:18 in weight base. When the substrate contained free EPA+DHA over 68%, the obtained phosphatidylcholine (PC) contained more than 31% of EPA+DHA. And when the substrate was 99.4% EPA, the obtained PC contained more than 45% of EPA, indicating that more than 90% of EPA was incorporated into sn-2 position of the PC molecule.

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A flow injection analytical system for simultaneous determination of glucose, ethanol, glycerol and sulfite was developed. The system was composed of immobilized enzyme columns, a multichannel potentiostat and a multichannel flow cell and/or a single channel flow cell equipped with a dialysis membrane covered platinum electrode. Gelatin pre-treatment was performed for the measurement of sulfite content, because some interference substances in white wine interfered the measurements. Carrier solutions used were 0.1M phosphate buffer (pH 8) for sulfite and ethanol, 0.1M phosphate buffer (pH 6) for glucose and 0.125M carbonate buffer (pH 10) containing 30mM ammonium sulfate for glycerol. The flow rates were 1.3, 2.5, 1.3 and 1.1ml/min for sulfite, ethanol, glucose and glycerol, respectively. The values of these four compounds in white wines obtained by this FIA method coincided well with those by F-Kit, HPLC and/or GC methods.

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In the previous paper, the authors have reported on the white precipitates found in syrup of canned Iyo orange segments which had been prepared by addition of β-cyclodextrin (β-CD) or Dexyparl K-100 (α-CD rich CD formula) and presumed that those precipitates may be inclusion compounds of CD with components of juice sac membrane. This report dealt with the identification of acidic and neutral fractions of guest compounds included in those inclusion compounds. After hydrolyzing the CD moiety of them, guest components were extracted and analyzed by means of thin layer chromatography and gas chromatography. The guest compounds of β-CD inclusion compound were fatty acids, sterols and sterol esters. The K-100 inclusion compound was found to be α-CD inclusion compound and the guest compounds of it were fatty acids, whereas no sterols and their esters were recognized in it. Limonin and/or nomilin were also not detected in those inclusion compounds.

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Comparative measurements of a newly developed microrheometer with a standard dynamic rheometer for concentrated liquid confirmed that the complex modulus was accurately measured with the present instrument by inputting an exact thickness value with a precision in 0.01mm for a pasty sample. To detect the sample temperature indirectly, a foil sensor was attached behind the black metal plate touching the sample. In addition, for the double-side shear mode, it was possible to determine the contact area of two grains using a camera from only one side, by putting a transparent plate over another one. Statistical investigations of the data of steamed waxy rice grains indicated that G^* values were independent of the time elapsed after steaming. Highly reliable G' values were obtained in the range of 15% of the coefficient of variance, when the grains were sandwiched between the plates to the extent of 30% of the initial thickness.

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A semiempirical model describing the temporal variations of the biomass and temperature of an industrial sorghum brewing fermentor is proposed. It appears that using the averaged values of the variables of the highly complicated, nonisothermal, and nonhomogeneous solid state fermentation (SSF) system to describe its behavior is appropriate. The result of analyzing the available experimental data reveals that the present approach provides a feasible way of characterizing a typical SSF system.

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Three kinds of trisaccharides were synthesized using condensation action of α-galactosidase (EC 3.2.1.22) from pyrcnoporus cinnabarinus on the mixture of galactose and sucrose. The condensation products were isolated and their structures were investigated by acid and enzymatic hydrolysis, and methylation analysis. The three trisaccharides isolated were identified as raffinose, planteose, and 3^G-α-galactosylsucrose. Conditions for synthesis of the trisaccharides by condensation action of the α-galactosidase were studied. The yield of the trisaccharides was approximately 15% based on the amount of galactose used, when α-galactosidase (40 units/ml) was incubated with 10% (w/v) galactose and 60% (w/v) sucrose for 48h at pH 5.0 and 60°C.

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Turmeric finger as one of the most popular spices has been widely used for food manufacturing. However, it has also been a major cause of bacterial infestation of food materials especially in curry, ham and sausage manufacturing. In this study decontamination of bacteria in turmeric finger by electron beam irradiation was evaluated by comparing with several other decontamination methods: i.e., boiling, microwave irradiation, treatment by twin screw extruder and gamma-ray irradiation. By estimation of colony counting on nutrient agar plate, turmeric finger without any treatment gave total viable cell at 10⁸/g. Turmeric finger which was irradiated by electron beam at 10kGy dose dramatically reduced thermotolerant cell population below self restriction level (<1000/g), which has been required by food hygiene law. The same level of sterilization effect was obtained only by gamma-ray irradiation at 10kGy and 20kGy. On the other hand, although treatment through twin screw extruder slightly reduced bacterial numbers, neither boiling nor microwave irradiation gave sufficient decontamination effect on turmeric fingers.

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