A new preparation method of stable frozen sauce was investigated and textural properities of the sauce were measured. Cooked white sauce was frozen slowly to form tight starch gel. After 24 hours, sodium alginate (0.15%) and sucrose fatty acid ester (0.10%) were added to the thawed white sauce and homogenized under the pressure of 300kg/cmcm2. The white sauce was kept under 15°C through the process. A part of the homogenized white sauce was stored in a freezer (approximately -20°C) and the other was stored in a refrigerator (approximately 5°C) for 14 days. Duing the storage period, effects of storage time and temperature on apparent viscosity and syneresis ratio of the homogenized white sauce were determined. The following results were obtained. (1) Such properties of the homogenized white sauce as apparent viscosity and syneresis ratio were very stable during the storage period. (2) The textural properties of the homogenized white sauce was not affected remarkably by the storage temperature. (3) Texture of the homogenized white sauce was evaluated organoleptically as high as that of the fresh one. (4) Addition of sodium alginate and sucrose fatty acid ester was necessary to control the apparent viscosity and to retard the syneresis of the homogenized white sauce.

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As the results of a further investigation of amino acid-sugar compounds in green tea, 1-deoxy-1 (L-aspartic acid)-D-fructose, 1-deoxy-1-L-threonino-D-fructose, 1-deoxy-1-L-serino-D-fructose and 1-deoxy-1-L-alanino-D-fructose were newly identified. The process for production of Japanese green tea includes the heat treatment of crude green tea at temperatures above 100°C (hi-ire) to gain its characteristic flavor. Therefore, the changes in the amounts of the amino acid-sugar compounds above-mentioned during heating of crude green tea at 110°C, 130°C and 150°C for 10, 30 and 50min were investigated. The results indicated that their amounts increased continuously on heating at 110°C, but on heating at 130°C or 150°C they increased to a maximurn and then decreased. The sensory evaluation of these green teas for estimating the intensity of hi-ire revealed that the amino acid-sugar compound contents were at a maximum at slightly excessive intensity of hi-ire.

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As we reported previously, the oxidation of oils and related foods was accompanied by emission of ultraweak chemiluminescence. It was expected that the retardation of oxidation rate by the addition of antioxidants would reduce the emission intensity of oils. Therefore, we attempted to examine the antioxidant activity by the measurement of the emission intensity. Chemiluminescence was measured at 100°C by using a single photoelectron counting system ("CHEMILUMINESCENCE ANALYZER"). Apparent decreases in their emission intensities were observed when fatty acid methyl esters prepared from rapeseed oil were mixed with antioxidants (BHA, BHT, α-, γ- and δ-tocopherols) in 0.02%. In comparison with the results of AOM (Active Oxygen Method) and Oven Tests of the same sample esters, the emission intensity was closely correlated with AOM hours, except α-tocopherol, which could have the most significant quenching effect of singlet oxygen among tocopherols. With new antioxidants (5-bromo-3, 4-dihydroxy benzaldehyde and rosemary extracts), the antioxidative activity was also detected as the decreased chemiluminescence. This new method is very simple in the procedure and very sensitive, by which even 1mg of antioxidative materials can be tested. Accordingly we expect to use this method as a preliminary test for the screening of antioxidants.

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Nucleide 2'-, 3'-and 5'-phosphates were separated by anion exchange chromatography. The analysis was carried out using a column of φ9mm×250mm packed with Hitachi Model 2630 anion exchanger, by the stepwise eluting method.
Method 1. After nucleosides and purine and pyrimidine bases were eluted by 0.05M ammonium chloride-ammonia (pH 5.6), 5'-CMP, 5'-UMP, 2'-CMP, 3'-CMP, 5'-GMP, 5'-IMP, 2'-AMP, 2'-GMP, 3'-AMP, 3'-GMP could be eluted separately by 0.3M ammonium chloride-ammonia (pH 9.7).
Method 2. After nucleosides and purine and pyrimidine bases were eluted by 0.1M ammonium acetate-acetic acid (pH 4.6), 5'-CMP, 5'-AMP, 2'-UMP, 3'-UMP, 5'-IMP, 3'-AMP, 2'-GMP, 3'-GMP could be eluted separately by 0.3M ammonium chloride-ammonia (pH 10.3).
Method 3. After nucleosides and purine and pyrimidine bases were eluted by 0.2M ammonium acetate-acetic acid (pH 4.6), 2'-GMP, 3'-AMP, ADP, 3'-GMP could be eluted separately by 0, 3M ammonium acetate-ammonia (pH 9.5) and then ATP by 0.6M ammonium chloride (pH 5.2).
The nucleotides in leafy vegetables (Head lettuce, Chinese cabbage, Cabbage) were determined by these methods. The very small amounts of 5'-CMP, 5'-UMP, 5'-AMP, 5'-GMP, ADP, ATP were observed in these samples.

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The shrimp Pandalus borealis has been said to be one of the most unpalatable species among prawns and shrimps when cooked but has a unique taste of strong sweetness and high viscosity when eaten raw. The taste-active components in raw muscle of the shrimp were studied. The extractive components in 100g of the muscle consisted of glycine (526mg), arginine (181mg), alanine (90mg), proline (71mg), IMP (35mg), AMP (8mg), hypoxanthine (14mg), trimethylamine oxide (537mg), homarine (304mg), propionic acid (28mg), acetic acid (23mg), Na⁺(170 mg), K⁺(139mg), Cl^-(241mg), PO₄^3-(358mg) and 20 kinds of other organic compounds and inor- ganic ions. The sensory analysis revealed that a synthetic extract, prepared from the chemicals on the basis of the analytical data, satisfactorily reproduced the taste of the natural extract except for odor. The aqueous muscle extract showed an extraordinarily high viscosity and contained a large quantity of protein, when compared with those of other prawns and shrimps. Thus, the characteristic sweetness may be derived largely from glycine and is enhanced by the aqueous extractable proteins which afford viscosity and elaborate the taste in cooperation with other extractive components, so that the cooking results in the coagulation of the proteins and spoils the taste accordingly.

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Polyphenol oxidase (EC 1.10.3.1) of immature fruit of Satsuma mandarin (Citrus unshiu Marc., av. wt 4.2g) was 100-fold purified by the use of ion exchange chromatography and gel filtration. The enzyme preparation oxidized the polyphenol solution (PP) obtained from the immature fruit, and also oxidized 1, 2, 3-trihydroxybenzenes such as pyrogallol and gallic acid and o-diphenols such as chlorogenic acid. Disc gel electrophoresis revealed that the enzyme preparation contained at least two isozymes. One of them oxidized PP and chlorogenic acid but did not act on pyrogallol and DL-dopa. The chlorogenic acid oxidizing enzyme activity (ChO) of the enzyme preparation was found to have an optimum pH at pH 7.2 and to be stable over the pH range of 5 to 8. ChO was inactivated with heating at 65°C for 5min. ChO activity was inhibited by potassium cyanide, sodium diethyldithiocarbamate, thiourea and L-ascorbic acid. These effects of pH, temperature and various compounds on ChO activity were very similar to those on browning reactions of PP and chlorogenic acid. It is concluded from the experimental results that ChO may be responsibie for the acceleration of the browning of PP in immature Satsuma mandarin fruit.

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The addition order of reagents affected remarkably on the formation of nitrosodimethylamine in the study of the effect of erythorbic acid on the formation of nitrosodimethylamine from dimethylamine and potassium nitrite. The reactions of dimethylamine with potassium nitrite and erythorbic acid with potassium nitrite occurred in a moment and the following addition order of reagents had most Significant inhibitory effect on the formation of nitrosodimethylamine: acetic acid, erythorbic acid, potassium nitrite and dimethylamine.

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