Nutritional value and sensory characteristics of meat eating quality of Australian prime lambs supplemented with pelleted canola and flaxseed oils: fatty acid profiles of muscle and adipose tissues

The effects of canola or flaxseed oil dietary supplementation on Longissimus thoracis et lumborum (LTL) muscle and visceral adipose tissue fatty acid (FA) profiles and meat sensory traits in Australian prime lambs from different breeds were investigated. Sixty lambs were fed one of the following pellet treatments: no oil (Control), 2.5% canola, 5% canola, 2.5% flaxseed and 5% flaxseed, balanced by breed (purebred Merino, and first-cross lambs from Corriedale rams mated to Merino ewes and White Suffolk rams mated to Corriedale ewes). Lambs were individually supplemented daily with 1 kg of oil-enriched wheat-based pellets throughout the 7-week feeding trial, after a 3-week adjustment period and had unlimited access to water and lucerne hay. At the end of the feeding trial, all animals were slaughtered. From each carcass, an LTL muscle sampled at the 12/13th rib interface and a visceral adipose tissue sample from the liver area were taken and subjected to fatty acid analysis. Another LTL muscle sample was removed and utilised for sensory evaluation of meat eating quality. The inclusion of 5% flaxseed oil significantly decreased n-6/n-3 ratio in both tissues. The muscle from lambs fed 5% oil supplements had higher omega-3 long-chain polyunsaturated FA (n-3 LC-PUFA) contents and reached the claimable health-benefitting value without deleterious sensory effects. The n-3 LC-PUFA component in visceral adipose tissue was negligible. Tissue FA profiles and sensory quality were influenced by breed. There were significant interactions between oil supplementation and lamb breed on some visceral adipose FA and meat juiciness. These findings indicate that a combination of dietary manipulation and lamb genetics can be used as an effective management tool to deliver a nutritionally improved n-3 LC-PUFA lamb to consumers.