Meat oxidative stability in lambs given almond skin to partially replace maize

The effects of feeding lambs diets containing two levels of almond skin on meat oxidative stability were investigated. Male lambs (n = 30, 2 months old, body weight 12.7 ± 2.07 kg) Valle del Belice × Pinzirita were assigned to 3 dietary treatments and fed ad libitum for 56 days with: a concentrate-based diet (CON) or CON containing 140 (A14) or 280 (A28) g/kg of dried almond skin in replacement of maize. Vitamins and hydrophilic antioxidant capacity were assessed in fresh meat, while colour and lipid oxidation were evaluated over 7 days of refrigerated storage. Data from fresh meat were statistically analysed using one-way ANOVA, whereas shelf-life trial data were evaluated using a mixed-effects model. Almond skin inclusion affected the antioxidant capacity of meat, showing different results: Folin-Ciocalteu and ferric reducing antioxidant power (FRAP) assays showed a decreased reducing activity of the extract, while an improved radical scavenging activity was observed with the Trolox equivalent antioxidant capacity (TEAC) assay. Ferrous ion chelating activity (FICA) and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays showed no differences. A reduction of the total tocopherol content was observed in A28 treatment compared to the others. Neither the colour nor the lipid oxidation was influenced by the dietary treatment, except for the TBARS (Thiobarbituric Acid Reactive Substances) values in raw meat, which tended to increase in A28 treatment. The study evidenced that 140 g/kg dietary almond skin in lambs may be a successful strategy for replacing maize without detrimental effects on meat oxidative stability.