Abstract
Pork meat was freeze-dried with the usual method after one of the following pretreatments; (a) no treatment, (b) addition of antioxidant and (c) additions of antioxidant and soy sauce. It was stored for a year at considerably high temperature, 37°C.
Acid and carbonyl values of the meat fat increased gradually during storage. Thiobarbituric acid and peroxide values also showed a slow increase with an apparent correlation between themselves. The meat, however, maintained its suitability as food. The oxidation degree of the meat was subjected to detailed gas chromatographic analysis of fatty acid composition on both free and neutral states. The P/O ratio (molar ratio of palmitic acid/oleic acid) determined from the amount of free fatty acids increased during storage, indicating certain correlation with oxidation rate. The P/O value, therefore, was confirmed to be characteristic of fat. There was no much difference in the sensory test of the seven-months samples with regard to the parts of pork and pretreatment. However, a slightly better result was obtained with (c) treatment.
It was concluded from these results that freeze-dried pork was preservable at least seven months at 37°C with little deterioration, if the storage vessel was covered with raminated aluminum foil and the meat was exposed to nitrogen gas. Addition of antioxidants and soy sauce was highly effective for maintaining meat quality.
