1988 Volume 14 Issue 3 Pages 81-88
Changes of chemical properties and composition of total lipids in nameko mushroom, pholita nameko during storage were studied. Nameko mushrooms were stored at 20°C for 6 days, 5°C for 8 weeks and -25°C for 5 months, respectively. The results obtained were as follows :
(1) Total lipid content in nameko mushroom stored at 20°C showed a tendency to decrease during storage. Then acid value and peroxide value of total lipids in samples stored at 20°C and 5°C increased during storage and the above changes show the oxidation of total lipids. While those in samples stored at -25°C showed scarcely the above changes.
(2) With regard to the changes of lipid composition of total lipids during storage, the decrease of glycolipid and phospholipid fraction contents and the increase of neutral lipid fraction content in total lipids were observed at three kinds of stored temperature. Especially these changes were remarkable in the case of samples stored at 20°C.
(3) Concerning the changes of lipid composition of neutral lipid, glycolipid and phospholipid fractions, the decreases of triacylglycerol content in neutral lipid fraction, cerebroside content in glycolipid fraction and phosphatidylethanolamine and phosphatidylcholine contents in the phospholipid fraction were observed at three kinds of stored temperature, especially these changes were remarkable in the case of 20°C storage.
(4) On the changes of fatty acid composition of total lipids and the above three lipid fractions, the decrease of 18 : 2 acid content and the increase of total saturated fatty acid contents were observed in the cases of 20°C and 5°C storage. On the other hand, the changes of fatty acid composition of the above lipid fractions were hardly observed at -25°C storage.
(5) From the above results, the storage at -25°C was effective for 5 months against the rancidity of lipids in nameko mushroom and the storage at 5°C was effective for 3 weeks, but the storage at 20°C was not effective.
