Rheological properties and spinnability of soy protein as well as methods of prevention of lysinoalanine (LAL) formation were studied. It was found that dopes prepared from 18-25% protein concentrates and 1.0-2.0% sodium hydroxide showed a good transitional region from rubber-like elasticity to rubber-like flow, as frequence (ω) in limitation was increased from -1 to 1; and also the dope showed good spinnability When prepared in the above manner. But LAL formed in the dope and fiber spun under these conditions. Addition of L-cysteine hydrochloride to the dope decreased the amount of LAL to about 1/2 to 1/3. The dope prepared by the above method had good spinnability, and the texture of spun fiber prepared from this dope was fit for meat analogue production.

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The study was conducted in order to find suitable processing conditions of blanching and/or freezing treatment to improve the texture of sweetpotato chips made of sweetpotato slices having a thickness of 2.0mm. The results obtained were as follows: (1) Optimal blanching time before freezing was 20-30 sec. in boiling water, 60-120sec. in ordinary pressure steam and 20-40sec. in hot oil (120°C), respectively. (2) Freezing temperature did not affect the texture of chips appreciably in the range of -5°C to -40°C. (3) The effect of freezing time under -22°C on the chips texture was not appreciable in case of freezing time more than 30min. which was long enough to freeze the slices. (4) Chips fried by deep-fat frying at 145°C-155°C after thawing were remarkably improved on crispness as much as hardness which decreased to approximately onefourth of untreated ones depending on the varieties of sweetpotato. (5) Sweetpotato varieties having high starch content such as Norin No.1, Gifu No.1 and Koganesengan resulted in a high quality of chips concerning fiavor and appearance when evaluated by the sensory test.

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(1) Chemical properties of total and neutral lipids in seeds of persimmon, Diospyros kaki ("Fuyu", "Zenjimaru" and "Koshuhyakume") were studied by means of thin-layer and gasliquid chromatography. (2) Total lipid contents in seeds of three varieties of persimmon were 0.43-0.67% and neutral lipids were 81.7-88.6% of the total lipids. Lipid compositions of the above three neutral lipids were resemble and consisted of triacylglycerides (23.0-33.7%), 1, 3-diacylglycerides (3.4-10.7%), 1, 2-diacylglycerides (8.2-11.8%), sterolesters (16.0-17.5%), hydrocarbons (4.2-7.6%), free fatty acids (1.8-2.8%), fatty alcohols (1.8-3.8%), sterols (3.8-13.7%) and unknown materials (17.2-22.0%). Main components in neutral lipids were triacylglycerides, unknown materials, sterolesters and 1, 2-diacylglycerides. (3) Fatty acid compositions of total lipids, triacylglycerides, 1, 3-diacylglycerides, 1, 2-diacylglycerides, sterolester and free fatty acids were studied by gas-liquid chromatography, and 11-16 kinds of fatty acids were identified. Main fatty acids in these lipids were oleic (21.7-50.4%), linolic (11.2-47.4%) and palmitic acids (13.0-37.9%).

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Volatile components of wasabi and horse radish were studied by gas chromatography (GC) and GC-mass spectrometry. The main volatile component of both samples was allyl isothiocyanate, while, in horse radish, β-phenylethyl isothiocyanate was contained in a relatively large amount as a radish-like flavor. In the present experiment, the typical flavor component of wasabi could not be found in GC analysis. Allyl isothiocyanate in methanol solution converted to the component, having a allyl sulfides like odor with heating.

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Alkyl isothiocyanates were gradually changed into the components having an alkyl sulfides like odor in methanol solution. To clarify the structures of these components, they were separated by silica gel column chromatography, and examined by IR, NMR and mass spectrometry. Alkyl isothiocyanates were found to be converted to methyl alkyl thiocarbamates by the addition of methanol in the solution. Ten % of allyl isothiocyanate changed into methyl allyl thiocarbamate in methanol solution for a week. It is assumed that alkyl thiocarbamates will be produced from alkyl isothiocyanates by the attack of reagents having electron-releasing property.

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New sardine products, named "sardine portion" were developed. Surmised problems in commercialization of the sardine products were the oxidation of sardine oil therein during storage and the contamination of sardine oil into frying oil during deep fat frying. Two series of experiments were carried out. (1) Sardine portions with or without tocopherol were stored for 6 months at 2 different conditions, namely (1) at -27°C, (2) repetition of storage at 5°C for 1 day after having stored at -27°C for 3 weeks (as a model of a freezer in a bad condition). Periodically, peroxide and acid values of the oils in the sardine portions were measured and their qualities such as flavor, taste and colour were tested organoleptically. Under the condition (1), the sardine portions were kept without deterioration for 6 months. Under the condition (2), the antioxidative properties of tocopherol were observed clearly. (2) Sardine portions were fried with soybean oil at feeding facilities. The fatty acid composition of the frying oil were measured by gas chromatography. As the C_22-6 fatty acid content was none or trace in the frying oil, the contamination of sardine oil into frying oil seemed to be negligible.

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A new rapid and convenient method was developed for measuring sugar content of Citrus juice based on conductometry. The addition of strong electrolyte to Citrus juice was attempted to make the conductivity of juice depend upon only its sugar content, not its electrolytes, organic acids and ash, by burying their influence in the conductivity of strong electrolyte. The behavior of citric acid and potassium citrate mono basic in a KCl solution was closely investigated by choosing KCl as a strong electrolyte. The least influence was attained at the KCl concentration of 0.6M. Pectin and water-insoluble solids (pulp)in Citrus juice did not affect the conductance measurement. The regression analysis of sugar content upon conductivity was made by using the model juice based on Satsuma Mandarin juice. Furthermore, the correction term of the KCl concentration was introduced to the regression line to find out the dependence of it for the KCl concentration. The recovery test gave 100.8% in average and the accuracy of this method was comparable to that of chemical ones, phenol-sulfuric acid method. This sugar measuring method is rapid, convenient and non-skilled and will attain further accuracy with the development of a suitable device for it.

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Microbicidal effects of various kinds of AWASEZU (processed vinegar) against 19 strains that included bacteria, yeasts and molds, were investigated. The following results were obtained. (1) Microbicidal activity of vinegar against bacteria was increased by sodium chloride and decreased by glucose at a concentration of 1-15% and 5-45%, respectively. On the other hand, the activity against yeasts was decreased by both sodium chloride and glucose, and that against molds was decreased by sodium chloride, but was increased by glucose. (2) Monosaccharides and sugar alcohols demonstrated the same microbicidal effect as did glucose, likewise, inorganic salts displayed the same reaction similar to that of the sodium chloride, although, with some exceptions. (3) Bactericidal activities of three kinds of AWASEZU and plain vinegar (2.5% acidity) were tested. These AWASEZU were NIHAIZU (2.5% acidity vinegar, 3.5% NaCl), SANBAIZU (2.5% acidity vinegar, 3.5% NaCl, 10% sucrose) and AMAZU (2.5% acidity vinegar, 10% sucrose). The strongest bactericidal activity was demonstrated by NIHAIZU, followed by SANBAIZU, plain vinegar and AMAZU in decreasing order. However, when soy sauce was used instead of sodium chloride, the bactericidal activity of the plain vinegar was the strongest, followed by AMAZU, NIHAIZU and SANBAIZU in this order. The decrease in the bactericidal activity of NIHAIZU and SANBAIZU seemed to have been caused by the increase in the pH value.

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As reported in the previous paper (this journal: 27, 188 (1980)), the draff from coffee-making can be converted to the active carbon by the treatment with zinc chloride. Some methods belonging to the category of gas-activation were adopted to obtain the product with an excellent quality, and/or to improve the activating procedure. Among these tested, a product with relatively good quality was obtained by steaming char with about 10% moisture, or by combined steaming of carbonized material including 100-150% (w/w) of zinc chloride at 900°C for 3-4hr. By applying steam pressure (1.5kg/cmcm²) during the activation process, an excellent active carbon was obtained in a short period.

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