Alfaia Cristina M, Alves Susana P, Pestana José M, Madeira Marta S, Moreira Olga, Santos-Silva José, Bessa Rui Jb, Toldrá Fidel, Prates José Am
1 CIISA, Faculdade de Medicina Veterinária, Universidade de Lisboa, Lisboa, Portugal.
2 UNIVATES, Centro Universitário Univates, Lajeado, RS, Brasil.
Food Sci Technol Int. 2017 Apr;23(3):209-221. doi: 10.1177/1082013216674137. Epub 2016 Oct 22.
In the present study, it was hypothesized that the incorporation of fatty acids is distinct among ruminant tissues and that it could be modulated by diet composition. To test this hypothesis, fatty acid composition, including conjugated linoleic acid isomers, of the most relevant beef by-products (brain, heart, kidney, liver, pancreas and tongue) from young bulls those fed distinct silage levels was assessed. Data indicated a large variation in fatty acid profile and conjugated linoleic acid composition among edible by-products. The most abundant fatty acids were C16:0 (kidney), C18:0 (heart and liver) and C18:1 c9 (brain, pancreas and tongue) followed by C20:4 n-6, except in brain (C22:6 n-3 predominates). Brain, as shown by principal component analysis, presents a distinct fatty acid composition compared to the other beef by-products analysed. In addition, high silage diet relative to low silage diet promoted an increase of n-3 polyunsaturated fatty acid, t11, t13 and t11, c13 conjugated linoleic acid in heart, kidney, liver and pancreas. Overall, the data suggested that beef by-products had, in general, high contents of cholesterol, saturated fatty acid and trans fatty acid, as well as high levels of conjugated linoleic acid. Therefore, from a nutritional point of view they are recommended only in small amounts as part of a balanced diet.
在本研究中，我们假设反刍动物组织中脂肪酸的掺入情况各不相同，并且其可能受到饮食组成的调节。为了验证这一假设，我们评估了来自饲喂不同青贮饲料水平的年轻公牛的最相关牛肉副产品（脑、心脏、肾脏、肝脏、胰腺和舌头）的脂肪酸组成，包括共轭亚油酸异构体。数据表明，可食用副产品之间的脂肪酸谱和共轭亚油酸组成存在很大差异。最丰富的脂肪酸是C16:0（肾脏）、C18:0（心脏和肝脏）和C18:1 c9（脑、胰腺和舌头），其次是C20:4 n-6，但脑除外（C22:6 n-3占主导）。主成分分析表明，与其他分析的牛肉副产品相比，脑呈现出独特的脂肪酸组成。此外，与低青贮饲料日粮相比，高青贮饲料日粮促进了心脏、肾脏、肝脏和胰腺中n-3多不饱和脂肪酸、t11,t13和t11,c13共轭亚油酸的增加。总体而言，数据表明牛肉副产品通常含有高含量的胆固醇、饱和脂肪酸和反式脂肪酸，以及高水平的共轭亚油酸。因此，从营养角度来看，建议仅将其少量作为均衡饮食的一部分。
