The effect of different forms of sunflower products in diets for lambs and storage time on meat quality

Abstract

The aim of the study was to determine the effect of sunflower products addition to lamb diets on lipid metabolism indices in blood plasma, carcass characteristics and longissimus dorsi muscle fatty acid (FA) composition. The experiment was performed on 24 Corriedale lambs weighing 22.9±1.89kg, assigned into 4 blocks of 6 animals each (according to the initial body weight), as a randomized complete block design. The control diet (CON) consisted of (g/kg dry matter; DM): meadow hay (188), ground corn (399), barley meal (223), soybean meal (136), sunflower meal (38.0) and vitamin-mineral premix (16.0). The experimental lambs additionally received different forms of sunflower products (g/kg DM): calcium salts of sunflower oil (CAS; 37.9), sunflower seeds (SFS; 68.6) or sunflower oil (SFO; 41.7). Furthermore, samples of longissimus dorsi muscle were frozen at −30°C to study the stability of FA during short- (1 month) and long-term (3 or 6 months) storage. Different forms of sunflower products did not affect lamb growth, carcass traits and chemical composition of longissimus dorsi muscle. Supplementing lambs with SFS diets negatively influenced lipid metabolism indices by increasing total cholesterol (TC) and low density lipoprotein (LDL) in blood plasma, without affecting the TC concentration in meat. The inclusion of different forms of sunflower products decreased nutritive value of meat by lowering the concentration of n-3 polyunsaturated fatty acids (PUFA). For that reason, we do not recommend sunflower products for lamb nutrition.Short and long-term storage increased total FA, saturated (SFA), monounsaturated fatty acids (MUFA), and interestingly, PUFA concentrations in meat. Such modifications could be associated with hydrolytic changes occurring during refrigerated storage.