Effects of dietary alpha-linolenic acid on the fatty acid composition, storage stability and sensory characteristics of pork loin

Effects of dietary alpha-linolenic acid on the fatty acid composition, storage stability and sensory characteristics of cooked pork were studied. Dietary alpha-linolenic acid (LNA) significantly (p < 0.05) increased the proportion of n-3 fatty acids and the degree of unsaturation in the neutral lipids and phospholipids. The increases in n-3 fatty acids were observed in the total lipids, triglycerides, phosphatidylethanolamine and phosphatidylcholine, and mainly consisted of C18:3n3, C20:5n3 and/or C22:5n3. The thiobarbituric acid reactive substances (TBARS) values (mg malondialdehyde per kg meat) of cooked vacuum packaged loins remained below 1.5, but in loose packaged loins TBARS values increased more than 3 times those of 0 time values during 2-day storage at 4 degrees C. The TBARS values of loins after LNA-enrichment were significantly higher than those of the control in both vacuum and loose packaging, and the increase of unsaturation in fatty acids had a strong prooxidant effect. The increase in dietary LNA enrichment increased oxidation (TBARS values) and had a detrimental effect on the acceptability of cooked pork loins held for 2 days in loose packaging. Copyright (C) 1996 Elsevier Science Ltd