The performance of 'Salmonella Assay' based on DNA hybridization and 'Salmonella Tek' based on enzyme linked immuno-sorbent assay for salmonella detection was investigated in naturally contaminated frozen and non-frozen chicken meat and frozen liquid whole eggs. The results were then compared with conventional methods. The optimum selective enrichment medium for the two kits was also investigated. In both kits, for selective enrichment as well as in conventional methods, Hajna's tetrathionate broth was the best medium. In frozen chicken meat and eggs, post enrichment with Gram negative broth was necessary for the detection using the 'Salmonella Assay', but not necessary in raw chicken meat. In detection using 'Salmonella Tek' post enrichment was not necessary in any of the foods tested. The performance in terms of salmonella detection for the two kits was almost equal to the results from the conventional method, when an appropriate media for each sample was used. These kits are suitable tools for the detection of salmonella in chicken meat and liquid eggs, because of their accuracy, simplicity in judging the results and shortened testing time.

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The physiological characteristics and chemical constituents of a small size mume fruit harvested at different maturities were determined during storage at 3, 15 and 30°C. 1) Weight loss was higher in the fruits harvested at earlier maturity and stored at higher temperature.2) The respiration rate of the fruits increased with rising of storage temperature, and the typical climacteric rise was observed at 30°C. At 15°C, the climacteric rise occurred showing markedly lower peak rate as compared with that at 30°C. Clear climacteric rise was not observed at 3°C. 3) Ethylene production increased after harvest and the rate was higher in the fruits harvested at advanced maturity and stored at higher temperature. 4) Early harvested fruits began yellowing of peel accompanied by degradation of chlorophyll after 2-4 days at 30°C whereas late harvested ones already showed beginning of yellowing at harvest. 5) The hardness of the fruits remarkably decreased during rising of the respiration rate or after the peak. 6) The citric acid content increased immediately after harvest then decreased, while malic acid steadily decreased. The changes were more pronounced at higher storage temperature. 7) Total amount of free amino acid increased markedly in early harvested fruits, but a little change was found in late harvested ones. 8) Contents of sugars decreased more rapidly when the fruits were harvested earlier and stored at higher temperatures. The change was conspicuous with glucose and sorbitol.

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The denaturation of carp skeletal myosin caused by freezing and thawing was measured by the decrease in Ca²⁺ -ATPase activity and by the increase in turbidity. The changes in activity was great at concentrations of myosin less than 0.1 mg/ml. At low ionic strength (60 mM KCl), the denaturation caused by freezing and thawing was protected in the presence of non-ionic surfactants, such as 0.01% Tween 20. At high ionic strength (500 mM KCl), the denaturation was protected in the presence of 0.01% SYglyster (polyglycerol fatty acid ester) ML-750, but Tween 20 was no effective for the protection. At myosin concentrations of less than 1.0mg/ml, the turbidity greatly increased. The addition of 0.005% Tween 20 was effective for the protection against increasing of turbidity. The effective concentration of Tween 20 was lower than that of sorbitol. Tween 20 and sorbitol acted synergistically in preventing denaturation of myosin.

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In order to improve the yield, shrinkage and hardness of salted mume fruit, the authors attempted to elucidate some factors for improvement of the salting method. The effect of initial NaCl concentration and Ca compounds content of the salted mume fruit was investigated. And mutual relationships between the hardness of salted mume fruit, pectic substances and Ca content were examined. The following results were obtained. 1) The yield of salted mume fruit increased with the declining of initial NaCl concentration. And the yield produced by using of the brine salting method with declining of initial NaCl concentration was about 20% higher than that produced by using of the dry salting method. 2) The declining of the yield, shrinkage, softening and increasing of pectin content in salted mume fruit were observed according to the increasing of initial NaCl concentration. 3) The yield, hardness and Ca content in alchohol-insoluble solid (AIS) of salted mume fruit increased with addition of Ca compounds. 4) The hardness of salted mume fruit, which included the large amounts of both hydrochloric acid-soluble pectin and sodium hydroxide-soluble pectin, and small amount of water-soluble pectin as pectic substances composition, was high. 5) With respect to the changes of cation contents in AIS by the brine salting method, Ca and Na ion contents increased, but Mg and K ion contents decreased.

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'Shirokaga' mume fruits (Japanese Apricot, Prunus mume Sieb. et Zucc., middle size cv.) were harvested at various maturities as materials for making Umezuke (a salted Japanese pickle), and the changes of chemical constituents were determined in the course of ripening after harvesting at 20°C. 1) Late-harvested fruits showed ethylene production even at harvest and the rate increased with the advance of harvest date. In early-harvested fruits, ethylene production occurred during storage at 20°C. The increase of ethylene production after harvesting became more rapid with the advance of harvest date. 2) The chlorophyll content and hardness of the fruit decreased remarkably during storage, coinciding with the rapid increase of ethylene production. 3) Linear increase of citric acid and linear decrease of malic acid were observed in the fruit during maturation on the tree, and roughly similar trend was observed during storage. 4) The amounts of alanine, serine, proline, valine, isoleucine and leucine of free amino acids increased during storage of the fruits, and especially the alanine content became 4.8-14.5 times the amount at harvest. 5) A significant decrease was observed in glucose and sorbitol contents during storage, and sucrose and fructose contents increased slightly following an initial decrease at an early stage of storage.

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