To prevent the quality deterioration in freezing and thawing of yellowtail (Seliola quinqueradiata) meat having weak resistance to freezing, the efficiency of dehydration treatment with some polymer sheets on thawing was evaluated by determining several quality of frozen-thawed meats. Results obtained are summarized as follows. 1. All polymer sheets used were effective for maintenance of quality and food sanitation of frozen-thawed meats. The dehydration-sheet thawing at 4°C was suitable for keeping the textural quality and low K value, and that at 10°C for retention of color of red meat. 2. The superior method for keeping the textural quality of frozen-thawed meats was to package under vacuum the fresh meat wrapped with polymer sheet before freezing, and thaw it in flowing water at 4°C. As the vacuum-packed frozen meat was likewise effective when thawed in still air of 4°C in the refregerator, the sheet treatment before freezing was of much practical use. 3. The low-temperature storage after dehydration sheet thawing of the frozen meat seem- ed to be effective slightly on the maintenance of the quality compared with that of ordinary frozen-thawed meat. 4. When the meat was kept in frozen storage for a long period, the maintenance of qual- ity of the thawed meat showed a tendency to be superior to ordinary frozen thawed meat in the sheet treated one.

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On the flavor deterioration of Japanese soup packaged into a pouch, a proper selection of laminated film for food packaging was proposed by showing the influences of oxygen permeability (a : cm/ cm • day • atm), storage period (T; day), the ratio of surface area (S; cm?) to volume (V; cm') of pouch. Samples were stored for 4 weeks at 25°C, which had been packaged into 6 kinds of pouches (9cm x 15cm; 200ml) made of the following laminated films; PET/LLDPE (a = 98 × 10-), PA/LLDPE (a = 28 x 10-4), PVDC-coated PA/LLDPE (a = 45 × 10-*), *PVDC-coated PA/LLDPE (a = 1.5 × 10-), EVOH/LLDPE (a = 0.3 × 10-*), PA/AL/LLDPE (a =0). The flavor of stored sample was sensory-evaluated with 8 panelists, while the changes in the gas chromatograms were traced throughout t h e storage. In order to correlate the flavor deterioration to the amount of oxygen permeated, the following equation was introduced ; a =p-a•T•S/V, where p is a partial pressure of oxygen in atmosphere and a, dimen- sionless number was defined as a specific volume of oxygen permeated. As the result, the flavor of packaged soup significantly deteriorated above a = 34 × 10-* Keywords: Food Packaging, Oxygen permeation, Flavor Deterioration

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