Mutagenicity found in a hydrolyzed animal protein (HAP) was analyzed on the samples collected along with the manufacturing process at some major HAP companies. Considerably high mutagenicity observed just after acid hydrolysis was decreased gradually by filtration with activated clay, alkaline treatment for 3-chloro-1, 2-propane diol (MCP) elimination, and activated charcoal treatment for decolorizing of the final product. Mutagenicity in the final product was below detection limit by forward mutation assay with Salmonella typhimurium TM 677 and was determined to be negative. This evidence suggested that the product tested in this study was safe for human consumption as commercially available seasonings. Extractability to four organic solvents suggested that the mutagen(s) transferred from hydrolysed protein to activated charcoal could be high polar, halogenated, or heterocyclic compounds.

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The fully matured fruits (mature red stage) cultured in a plastic house at Yuasa Experimental Farm, Kinki University were picked on September 12, 1995 and stored under various conditions. The conditions of storage were as follows ; (1) Group 1:25°C·3 days (sample number 1-a), 25°C·3 days+4°C·3 weeks (sample number 1-b), 25°C·3 days+4°C 6 weeks (sample number 1-c). (2) Group 2:4°C·3 weeks (sample number 2-a), 4°C·3 weeks+25°C·3 days (sample number 2-b), 4°C·6 weeks (sample number 2-c), 4°C·6 weeks+25°C·3 days (sample number 2-d). Each sample was analyzed for Hunter's color of fruits, flesh firmness, respiratory rate and contents of principal compounds (polysaccharides, free sugars and organic acids), and was applied to organoleptic test. The L and b values of the peel expressed by Hunter's color decreased slightly in general, but the a value increased strikingly. The a value of flesh from 1-c sample only increased slightly, but the value of the other samples did not increased. Decreasing of whole flesh firmness was observed for all samples. The decline of respiratory rate was recognized remarkably for samples from 1-b, 1-c, 2-a and 2-c. In all samples, the contents of AIS and starch decreased about by half, while the content of pectin decreased gradually during the storage. The content of sucrose which is dominant sugar in the fruit decreased gradually. Glucose content in 1-a or 1-b and c samples decreased or slightly decreased, but the content in 2-a, b, c and d samples increased slightly. Also, the content of citric acid developed a tendency to decreasing, while malic acid to increasing. The weight loss of the fruit became to higher as the periods of storage grew longer. The results of organoleptic test for all samples were 1-a>1-b>initial>2-a≥2-b>2-d >2-c≥1-c. From the results, it seems to be consider that fully matured 'Irwin' mango fruit could be preserved for approximately 3 weeks at 4°C.

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The effect of invertase activity on sucrose degradation in analyzing sugars (sucrose, glucose and fructose) in grape berries was investigated. Sucrose in squeezed grape juice was degraded rapidly, and this fact was thought to be mostly caused by endogenous invertase activity. Invertase activities and sucrose degradation in squeezed juice varied remarkably with grape cultivars. Only 'Steuben' had very low invertase activity and high sucrose concentration among 7 grape cultivars investigated. Invertase activities of other 6 grape cultivars were much higher than those of strawberry, Japanese pear, melon and Satsuma mandarin. Microwave heating treatment of grape pulp. was necessary before ethanol extraction against sucrose degradation during extraction for sugar analysis.

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Lipids and their fatty acid compositions of marine phytoplankton of 13 species were analyzed to search useful fatty acids (DHA, EPA, etc). Total lipid contents (%, in dry matter) were ranged within 3-16%, and the differences among 13 kinds were clearly recognized. From these contents, sample planktons were classified into 3 groups (about 15% : A, 8-9% : B, 3-7% : C;group with high FFA content is C, low is C'). In composition of total lipids, triacylglycerol of A group was the highest. And other differences were confirmed in the lipid composition. Major fatty acids in sample planktons were 14:0, 16:0, 16:1n7, 16:3n4, 18:0, 18:1n9, 20:1n9, AA (20:4n6), EPA (20:5n3), DHA (22:6n3), and differences in their compositions were observed among the samples. EPA content of Cylindrotheca closterium in B group was fairly high, and DHA content of Gymnodinium mikimotoi in C'groupwashigh. Thesetwospeciesmaybe useful resources of both fatty acids.

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Caramels produced by heating various monosaccharides above melting point in the presence of basic salt as catalyst showed the strong DPPH radical scavenging activity. (1) Caramels produced from pentose and hexose showed the strong DPPH radical scavenging activity, but caramels produced from sucrose and sorbitol did not. (2) The sodium citrate as catalyst and reaction temperature of 130°C were especially well suited for the production of caramel with the stable color intensity and the strong DPPH radical scavenging activity in the consideration of the caramel manufacturing process and its usage to food. (3) On dialysis of original caramel solution, the yield of retentate was about 75% from original caramel, and a part of color, reducing power and DPPH radical scavenging activity were mainly retained in retentate.

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