Description

As concerns regarding beef production systems on human health and animal welfare become more apparent, consumer interest in pasture-raised livestock has been steadily on the rise in the US. Such interest has increasingly led to questions about potential nutritional composition differences in beef from different production systems, such as grass-fed beef and grain-fed beef. The goal of this work was to conduct untargeted metabolomics analysis on a broad range of samples from the US beef supply chain to provide insight into how different finishing systems impact the beef metabolome and nutrient density. Here, we found that 191 out of 802 profiled compounds were different between grass-fed and grain-fed ribeye steaks (all, p < 0.05), with phytochemicals, vitamins, lipid, and amino acid metabolites emerging as the most discriminatory metabolite classes. On average, phytochemicals were 1.7-fold higher in grass-fed beef compared to grain-fed beef (p < 0.05) with considerable variation (4.4-fold) amongst individual farms, particularly within grass-fed beef systems. Alpha-tocopherol was 2-fold elevated in grass-fed beef, while nicotinamide was 1.3-fold elevated in grain-fed beef, respectively (p < 0.05). We also observed that 4- hydroxy-nonenal-glutathione, a common marker of oxidative stress, was 2.7-fold elevated in grain-fed beef samples (p < 0.05), with a 20-fold variation across individual farms. Future work will identify the source(s) of variation and best practices in beef systems to improve beef nutrient density and animal metabolic health.

Share

COinS
 

Effects of Different Production Systems on the Nutrient Density of Beef

As concerns regarding beef production systems on human health and animal welfare become more apparent, consumer interest in pasture-raised livestock has been steadily on the rise in the US. Such interest has increasingly led to questions about potential nutritional composition differences in beef from different production systems, such as grass-fed beef and grain-fed beef. The goal of this work was to conduct untargeted metabolomics analysis on a broad range of samples from the US beef supply chain to provide insight into how different finishing systems impact the beef metabolome and nutrient density. Here, we found that 191 out of 802 profiled compounds were different between grass-fed and grain-fed ribeye steaks (all, p < 0.05), with phytochemicals, vitamins, lipid, and amino acid metabolites emerging as the most discriminatory metabolite classes. On average, phytochemicals were 1.7-fold higher in grass-fed beef compared to grain-fed beef (p < 0.05) with considerable variation (4.4-fold) amongst individual farms, particularly within grass-fed beef systems. Alpha-tocopherol was 2-fold elevated in grass-fed beef, while nicotinamide was 1.3-fold elevated in grain-fed beef, respectively (p < 0.05). We also observed that 4- hydroxy-nonenal-glutathione, a common marker of oxidative stress, was 2.7-fold elevated in grain-fed beef samples (p < 0.05), with a 20-fold variation across individual farms. Future work will identify the source(s) of variation and best practices in beef systems to improve beef nutrient density and animal metabolic health.