• pasture
• myoglobin
• concentrate
• antioxidant
• Vitamin E

Multiple factors such as high temperature, light, free oxygen, metals, length of storage etc., can induce dangerous free radicals in products of animal origin, mainly affecting lipids, due to a major susceptibility of PUFAs to oxidation. This oxidative phenomenon is very harmful because it speeds up the quality deterioration of products of animal origin such as meat, altering color and reducing shelf life.
In order to reduce oxidative reactions, a balance between pro-oxidants and anti-oxidants is required in determining oxidative stability of lipids (Gravador et al., 2015). High levels of vitamin E in meat reduce oxidative reactions, offsetting endogenous muscle pro-oxidants.
The relationship between finishing diets with different vitamin E compositions and the final content of the vitamin found again in the lamb meat was investigated. Thirty male lambs were separated in five groups from six lambs each and, for 54 days pre-slaughter, assigned to either one of four concentrate diets (a barley/maize-based concentrate, a Megalac (saturated fat) containing concentrate, a protected linseed containing concentrate, or a citrus pulp and maize distiller grains-based concentrate) or a pasture based diet. After slaughter, analyses have been effected on the minced Muscle semimembranosus, packed in a high oxygen modified atmosphere (MAP: 80% O2: 20% CO2) with illumination, for up to 14 days.
The tied-up Vitamin E content to the stability of storage and color stability of lamb meat were measured after 0 (2 hours after packaging), 3, 7, 10 and 14 days of refrigerated storage with high oxygen levels. The color deteriorated and vitamin E content decreased significantly over time in all samples. Meat redness was significantly affected by diet, along with hue angle, which has been associated with browning in meat. Lower meat redness values and higher hue angle values were identified in meat from lambs fed pasture based diets. The vitamin E final content in meat was also significantly affected by diet. Meat from lambs fed grass diet for all through the experiment, in fact, introduced values of vitamin E clearly superior to those introduced by the meat from lambs fed concentrate diets.