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 stu died. Dietary alpha-linolenic acid (LNA) significantly (p < 0.05) incr eased the proportion of n-3 fatty acids and the degree of unsaturation in the neutral lipids and phospholipids. The increases in n-3 fatty a cids were observed in the total lipids, triglycerides, phosphatidyleth anolamine and phosphatidylcholine, and mainly consisted of C18:3n3, C2 0:5n3 and/or C22:5n3. The thiobarbituric acid reactive substances (TBA RS) values (mg malondialdehyde per kg meat) of cooked vacuum packaged loins remained below 1.5, but in loose packaged loins TBARS values inc reased more than 3 times those of 0 time values during 2-day storage a t 4 degrees C. The TBARS values of loins after LNA-enrichment were sig nificantly higher than those of the control in both vacuum and loose p ackaging, and the increase of unsaturation in fatty acids had a strong prooxidant effect. The increase in dietary LNA enrichment increased o xidation (TBARS values) and had a detrimental effect on the acceptabil ity of cooked pork loins held for 2 days in loose packaging. Copyright (C) 1996 Elsevier Science Ltd