Effect of slaughter age on the fatty acid composition of intramuscular and subcutaneous fat in lamb carcass of Awassi breed

Abstract

Eight male lambs of Awassi breed of about 6 or 12 months of age were procured from the local market and slaughtered. The results showed that carcass length, diameter, live body weight and hot carcass weights, C14:0, C15:0, C17:0, C16:1, C17:1, C18:1 trans-9, the n-6/n-3 ratio, and the total SFA for lamb carcass were significantly higher at higher slaughtering age. However, moisture, protein, fat, and ash percentage were similar among the two slaughtering ages. The pH in longissimus dorsi, C18:0, C18:1, C18:3, and the total MUFA were significantly higher at 6 month of age compared to 12 month of age. The PUFA/SFA ratio was similar among the slaughtering ages, but n-6/n-3 ratio was significantly higher at 6 month of age. Percentage of C15:0 and C17:0 in the intramuscular and subcutaneous fat and C14:0 in longissimus dorsi and semitendinos were significantly higher at 12 month of age. The C18:0 was significantly higher in longissimus dorsi, semimembranous, and semitendinos for carcass at 6 month of age. Awassi slaughtered at 6 and 12 month of ages displayed no significant differences in term of SFA. Awassi slaughtered at 6 month of age showed significantly higher percentage of C18:1 in longissimus dorsi and subcutaneous fat. In contrast, the C18:1 trans-9 was significantly higher in longissimus dorsi, semitendinos, and subcutaneous fat for Awassi at 12 month of age. Lamb slaughtered at 6 month of age displayed higher percentage of MUFA in longissimus dorsi compared with other muscles and subcutaneous fat. The C18:3 was significantly higher (P< 0.05) for Awassi at 6 month of age in semitendinos, semimembranous, and longissimus dorsi. Both slaughtering ages showed no significant difference in term of PUFA. The n-6/n-3 ratio of intramuscular for Awassi at 6 month of age was close to the recommended value for the human diet. Both slaughtering ages showed no significant differences in the PUFA/SFA ratio. meat from Awassi at 6 month of age are healthier for consumers and therefore slaughter age has an effect on the carcass characteristics and fatty acid composition.