Influence of α-tocopherol supplementation on trans-18:1 and conjugated linoleic acid profiles in beef from steers fed a barley-based diet

Abstract

<jats:p>The current study was conducted to determine the effect of different α-tocopherol (vitamin E) inclusion levels on<jats:italic>trans</jats:italic>(<jats:italic>t</jats:italic>)-18:1 and conjugated linoleic acid (CLA) profiles in subcutaneous and intramuscular fat of steers fed a barley-based diet. Fifty-six feedlot steers were offered a barley-based finisher diet (73% steam rolled barley, 22% barley silage and 5% supplement as-fed basis) with four levels of supplementary<jats:sc>dl</jats:sc>-α-tocopheryl acetate (340, 690, 1040 or 1740 IU/steer per day) for 120 days. Adding vitamin E to the diet had little effect on the overall fatty acid composition of intramuscular fat. The proportion of individual and total<jats:italic>t,t-</jats:italic>and<jats:italic>cis</jats:italic>(<jats:italic>c</jats:italic>)<jats:italic>,t</jats:italic>-CLA,<jats:italic>n</jats:italic>-3 fatty acids, total polyunsaturated fatty acids (PUFA), mono-unsaturated fatty acids and saturated fatty acids to PUFA ratio in subcutaneous fat were not influenced (<jats:italic>P</jats:italic>&gt; 0.05) by dietary vitamin E supplementation. Increasing levels of vitamin E led to linear reductions in<jats:italic>t</jats:italic>6-/<jats:italic>t</jats:italic>7-/<jats:italic>t</jats:italic>8-18:1 and<jats:italic>t</jats:italic>10-18:1 (<jats:italic>P</jats:italic>&lt; 0.05), and linear increase in<jats:italic>t</jats:italic>11-/<jats:italic>t</jats:italic>10-18:1 ratio (<jats:italic>P</jats:italic>&lt; 0.05) in subcutaneous fat. The content of 20:3<jats:italic>n</jats:italic>-6 and total<jats:italic>n</jats:italic>-6 in subcutaneous fat decreased (<jats:italic>P</jats:italic>&lt; 0.05) linearly with increasing amounts of vitamin E. The subcutaneous fat<jats:italic>n</jats:italic>-6:<jats:italic>n</jats:italic>-3 ratio showed a quadratic (<jats:italic>P</jats:italic>&lt; 0.05) response to vitamin E. In conclusion, although vitamin E supplementation has some potential to reduce<jats:italic>t</jats:italic>10-18:1 formation and increase<jats:italic>t</jats:italic>11-/<jats:italic>t</jats:italic>10-18:1 ratio in subcutaneous fat of cattle fed barley-based diets, the changes in the present study were limited and may not have been sufficient to impact on human health.</jats:p>

The trans-octadecenoic fatty acid profile of beef: Implications for global food and nutrition security

“…In support of this assertion, supplementing high-grain diets with vitamin E was shown to reduce t10-18:1 deposition, and maintain or increase VA proportions in beef Mapiye et al, 2012b). Similarly, feeding grain-based diets, and extracts or leaf-meals rich in secondary compounds such as condensed tannins (Jerónimo et al, 2010a;Rana, Tyagi, Hossain, & Tyagi, 2012;Vasta & Luciano, 2011), polyphenol oxidase (Mapiye et al, 2013a) and saponins (Brogna et al, 2014;Lourenço et al, 2010;Vasta & Luciano, 2011) have been reported to increase total and individual t-18:1 isomers, especially VA in ruminant meat, thus improving the VA to t10-18:1 ratio.…”

Value-addition of Beef Meat By-products: Lipid Characterization by Chromatographic Techniques

“…Palmitic acid C16:0 constituted the second major fatty acid detected [20][21][22][23][24][25][26][27][28] , followed by stearic acid C18:0, 10-19 , palmitoleic acid C16:1 cis, [2][3][4][5] , myristic acid C14:0, 2-4 and linoleic acid C18:2 n6, 2-10 . In the storage fat, the saturated fatty acids SFA were present in significantly p 0.05 greater amounts in calf and young bull 46.76 and 47.62…”

“…Bovines are ruminants and the rumen microflora conduct a hydrogenation process of unsaturated fatty acids making them saturated, increasing the total SFA amount 27 .…”

Enhancing the nutritional and health value of beef lipids and their relationship with meat quality

“…Elucidation of these effects requires considerable analytical effort for the determination and quantification of all single trans-18:1 fatty acid isomers in beef. Vaccenic acid (VA, is the most abundant trans-18:1 fatty acid isomer in beef from pasture-based fed cattle; however barleybased diets of British × Continental crossbred steers result in higher concentrations of 18:1trans-10 compared to VA and replaced VA as the major isomer in beef muscle (Mapiye et al, 2012). Also the muscle from feedlot-fed bulls, intensive indoor-fed Limousin bulls and Normand cull cows had higher 18:1trans-10 compared to VA contents (Alfaia et al, 2009;Bauchart et al, 2010;Kraft, Kramer, Schoene, Chambers, & Jahreis, 2008).…”