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Effects of cooking and drying methods on the taste component and microstructure of shrimp, Metapenaeus joyneri, were investigated. The nucleotides and their related compounds of fresh shirmp such as ATP, ADP, AMP, IMP, inosine and hypoxanthine were detected. AMP was detected as a trace amount in fresh shrimp, however, it increased up to 23.5∼45.7μ moles with cooking and drying due to the decomposition of ATP and ADP to AMP during cooking and drying. The major component of the free amino acids of fresh shrimp was arginine followed by glycire, lysine, proline and alanine. These free amino acids contents were 70% of the total free amino acids. One hundred grams of fresh shrimp contained 1,198㎎ (dry basis) of the total free amino acids. However, for hot air and freeze dried cooked shrimps it was decreased down to 342㎎ (dry basis) and 503㎎ (dry basis), respectively. It might be due to the dissolution of soluble amino acids during cooking. Hot air-and freeze-dried fresh shrimps was higher in hardness and brittleness but lower in cohesiveness and gumminess than hot air-and freeze-dried ones with boiling and microwave heating. Freeze dried shrimp had softer myofibril texture than hot air dried one. At the same time, more dense and multiporous structure in the tissue could be obtained from the hot air and freeze drying, respectively, after microwave heating of shrimps.
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