Double-muscling character influences the trans-18:1 and conjugated linoleic acid profiles in concentrate-fed yearling bulls

The effects of rapeseed cake intake during the finishing period on the fatty-acid composition of the longissimus muscle of Limousin steers and changes in meat colour and lipid oxidation during storage

Context Cold-pressed rapeseed cake is a by-product of biodiesel manufacturing that can be obtained on-farm after simple mechanical extraction of the oil. It has a high crude fat content and contains significant amounts of linoleic acid, which make it a promising lipid supplement to modulate meat fatty acid profile. However, previous studies have indicated that using unsaturated fats in beef cattle diets could promote lipid oxidation and reduce meat redness. Aims The present study aimed to evaluate the effects of supplementation of intensively fattened beef steers with cold-pressed rapeseed cake on the fatty acid composition of beef fat and changes in measures of meat colour and lipid oxidation during 6 days of aerobic storage. Methods Sixteen Limousin steers were divided into two homogeneous groups and were fed ad libitum with barley straw and a concentrate mixture supplemented with either PROGRAS (PROGRAS at 2.7% of the diet, high in palmitic acid C16:0 from palm oil; CTR, experimental control; n = 8) or cold-pressed rapeseed cake (CPRC at 14.8% of the diet; CPRC treatment; n = 8) for a period of 9 months. The growth performance and carcass traits were assessed. The intramuscular fatty acids were analysed and the colour stability and lipid oxidation were measured in meat stored aerobically at 4°C for 0, 3 or 6 days. Key results Slaughter bodyweight and average daily gain were not affected by the inclusion of CPRC in the diet. Nor were there any changes in carcass weight, conformation or fatness. The longissimus thoracis from CPRC-fed animals depicted a higher UFA–SFA ratio and a lower atherogenic index than did that from animals fed CTR. Feeding CPRC increased the oleic acid , the vaccenic acid and the rumenic acid proportions in the muscle fat without affecting the ratio of C18:1 trans-10 to C18:1 trans-11. The extents of lipid oxidation and colour deterioration during aging were not affected by the dietary treatments. Conclusions The use of cold-pressed rapeseed cake as a lipid supplement in beef-steer diet improved the fatty acid profile of muscle fat without compromising meat oxidative stability, animal growth performance and carcass characteristics. Implications The supplementation of beef-steer diet with cold-pressed rapeseed cake could be an advantageous economical strategy allowing exploitation of an important by-product of small-scale biodiesel manufacturing to provide consumers with healthier meat.

Characterization of the fatty acid composition of lamb commercially available in northern Spain: Emphasis on the trans-18:1 and CLA content and profile

A survey of commercially available lamb meat was performed in northern Spain in order to evaluate their fatty acid (FA) composition with emphasis on trans fatty acid (TFA) and conjugated linoleic acid (CLA) isomers. Samples were collected in spring (n=24) and winter (n=24) of 2013, and were obtained in about equal numbers from grocery stores and butcher-shops. Subcutaneous fat, known to be a sensitive indicator of TFA content in ruminants, was analyzed by GC-FID. In general, very few differences were observed between collection periods and type of stores because of the high variability within the groups that was believed to be associated with differences in genetics and feeding strategies. However, the 10t/11t ratio of all samples showed two clearly identifiable groups irrespective of the source: 1) when 10t/11t was >1, 10t-shifted samples; 2) when 10t/11t was ≤1, non-shifted samples where 11t-18:1 was the predominant isomer. These two groups were clearly identified and associated with distinct FAs using principal component analysis.

The scope for manipulating the polyunsaturated fatty acid content of beef: a review

Since 1950, links between intake of saturated fatty acids and heart disease have led to recommendations to limit consumption of saturated fatty acid-rich foods, including beef. Over this time, changes in food consumption patterns in several countries including Canada and the USA have not led to improvements in health. Instead, the incidence of obesity, type II diabetes and associated diseases have reached epidemic proportions owing in part to replacement of dietary fat with refined carbohydrates. Despite the content of saturated fatty acids in beef, it is also rich in heart healthy cis-monounsaturated fatty acids, and can be an important source of long-chain omega-3 (n-3) fatty acids in populations where little or no oily fish is consumed. Beef also contains polyunsaturated fatty acid biohydrogenation products, including vaccenic and rumenic acids, which have been shown to have anticarcinogenic and hypolipidemic properties in cell culture and animal models. Beef can be enriched with these beneficial fatty acids through manipulation of beef cattle diets, which is now more important than ever because of increasing public understanding of the relationships between diet and health. The present review examines recommendations for beef in human diets, the need to recognize the complex nature of beef fat, how cattle diets and management can alter the fatty acid composition of beef, and to what extent content claims are currently possible for beef fatty acids.

Estimates of genetic parameters for fatty acids in brisket adipose tissue of Canadian commercial crossbred beef steers

Heritability and genetic and phenotypic correlations between 15 individuals and 10 groups of fatty acids with a concentration greater than 0.5% in the brisket adipose tissue of 223 Angus and Charolais based crossbred commercial steers were estimated using univariate and bivariate animal models. Individual saturated fatty acids were low to moderately heritable, with heritability estimates ranging from 0.05 (C16:0) to 0.31 (C15:0). Individual monounsaturated fatty acids were low to moderately highly heritable ranging from 0.04 (9c C17:1 and 11c C18:1) to 0.51 (9c C14:1). Polyunsaturated fatty acid C18:2n-6 was moderately heritable (0.17). Among groups of fatty acids, heritability estimates ranged from 0.03 for branched chain fatty acid (BCFA) and n-6/n-3 to 0.16 for n-6 and Health Index. A range of low (0.00) to high (1.00) phenotypic and genetic correlations was observed among the 25 fatty acids considered in this study. In general, fatty acids such as conjugated linoleic acid (CLA) and 11t C18:1, with potential health benefits, showed significant antagonistic correlations with unhealthy fatty acids such as C14:0 and C16:0. The results from this study provide insight into the direct genetic control of host genes on fatty acid composition of beef tissues and will facilitate designs of genetic selection and/or genetic based diet management to improve fatty acid composition in beef cattle.

Effect of supplementing different oils: linseed, sunflower and soybean, on animal performance, carcass characteristics, meat quality and fatty acid profile of veal from "Rubia Gallega" calves

The fatty acid (FA) composition of longisimus dorsi (LD) and subcutaneous fat (SCF) from Rubia Gallega (RG) calves was compared for three dietary oil sources (linseed, LO; sunflower, SFO or soybean, SYO). Oils were added (4.5%) to a commercial concentrate and no differences on animal performance, carcass characteristics or meat quality among diets were noted. Total n-3 polyunsaturated FA (PUFA) increased in LD and SCF when feeding LO diet (P<0.001). The trans(t) FA profiles were dominated by t11-18:1, except when feeding SFO diet, where ∑t6- to t10-18:1 exceeded t11-18:1 leading the highest (∑t6-to t10-18:1)/t11-18:11 ratio in LD (P<0.05). The overall changes in n-3 PUFA and t18:1 when feeding LO and SYO could be viewed as positive for human health, but quantitatively it was apparent that most dietary PUFA were completely biohydrogenated. Inhibiting PUFA biohydrogenation will be an important next step to improve the FA composition of RG cattle.

Review:Trans-forming beef to provide healthier fatty acid profiles

Dugan, M. E. R., Aldai, N., Aalhus, J. L., Rolland, D. C. and Kramer, J. K. G. 2011. Review: Trans- forming beef to provide healthier fatty acid profiles. Can. J. Anim. Sci. 91: 545–556.Trans fatty acids are found naturally in foods, particularly in those derived from ruminant animals, such as beef and dairy cattle. Over the past few decades, human consumption of trans fatty acids has increased, but this has been mainly from products containing partially hydrogenated vegetable oils. The correlation of trans fatty acid consumption with diseases such as coronary heart disease has been cause for concern, and led to recommendations to reduce their consumption. Trans fatty acids, however, have differing effects on human health. Therefore, in foods produced from ruminant animals, it is important to know their trans fatty acid composition, and how to enrich or deplete fatty acids that have positive or negative health effects. This review will cover the analysis of trans fatty acids in beef, their origin, how to manipulate their concentrations, and give a brief overview of their health effects.