Effect of dietary soybean oil and antioxidants on fatty acids and volatile compounds of tail subcutaneous and perirenal fat tissues in fattening lambs.

Yongjia Peng,Jiakun Wang,Jianxin Liu,Jia Lin

doi:10.1186/s40104-016-0083-y

Abstract

BackgroundFat is the primary source of the volatiles that determine the characteristic flavors of animal products. Because unsaturated fatty acids (UFAs) contribute to changes in flavor as a result of the oxidation process, a feeding trial was performed to investigate the effects of dietary soybean oil or antioxidants on the fatty acid and volatile profiles of the tail subcutaneous (SF) and perirenal fat tissues (PF) of fattening lambs. Thirty-six Huzhou lambs were assigned to four dietary treatments in a randomized block design. The lambs’ diets were supplemented with soybean oil (0 or 3 % of DM) or antioxidants (0 or 0.025 % of DM).ResultsNeither soybean oil nor antioxidant supplementation had an effect on lamb growth (P > 0.05). In regard to tail SF, soybean oil supplementation increased the 18:2n6t (P < 0.05) and the total amount of volatile acids, whereas antioxidant supplementation increased the content of C18:2n6c and C18:3n3 (P < 0.05) but had no effect on the volatiles profile. In regard to PF, dietary soybean oil supplementation increased the C18:0 content (P < 0.01); decreased the C18:1 (P = 0.01), C22:1 n9 (P < 0.01) and total UFA (P = 0.03) contents; and tended to decrease the E-2-octenal (P = 0.08), E, E-2, 4-decadienal (P = 0.10), 2-undecenal (P = 0.14) and ethyl 9-decenoate (P = 0.10) contents. Antioxidant supplementation did not affect either the fatty acid content or the volatiles profile in the PF.ConclusionsTail SF and PF responded to dietary soybean oil and antioxidant supplementation in different ways. For SF, both soybean oil and antioxidant supplementation increased the levels of unsaturated fatty acids but triggered only a slight change in volatiles. For PF, soybean oil supplementation decreased the levels of unsaturated fatty acids and oxidative volatiles, but supplementation with antioxidants had little effect on PF fatty acids and the volatiles profile.

Highlights

Fat is the primary source of the volatiles that determine the characteristic flavors of animal products
Many studies have focused on protecting polyunsaturated fatty acids (PUFA) from oxidation through the use of antioxidants, and several synthetic antioxidants, such as butylated hydroxy anisole (BHA), butylated hydroxy toluene (BHT) and alpha tocopherol have been successfully employed to prevent or restrict lipid oxidation in meat products [11]
Because the effect of dietary soybean oil supplementation on the volatiles profile in the raw tissue of lambs is limited, we hypothesized that dietary soybean oil supplementation (3 % DM) might increase the level of PUFAs in tail subcutaneous and perirenal fat tissues of fattening lambs, with coinciding antioxidant supplementation to minimize PUFA oxidation in fat tissues

Summary

Introduction

Fat is the primary source of the volatiles that determine the characteristic flavors of animal products. Because unsaturated fatty acids (UFAs) contribute to changes in flavor as a result of the oxidation process, a feeding trial was performed to investigate the effects of dietary soybean oil or antioxidants on the fatty acid and volatile profiles of the tail subcutaneous (SF) and perirenal fat tissues (PF) of fattening lambs. E,E-2,4-decadienal, an oxidant product of linoleic acid (C18:2) and the source of “oil” aroma, which contributes to the change in flavor of the cooked meat of lambs whose diet was supplemented with sunflower oil [10]. Because the effect of dietary soybean oil supplementation on the volatiles profile in the raw tissue of lambs is limited, we hypothesized that dietary soybean oil supplementation (3 % DM) might increase the level of PUFAs in tail subcutaneous and perirenal fat tissues of fattening lambs, with coinciding antioxidant supplementation to minimize PUFA oxidation in fat tissues

Methods

Results

Conclusion