European Alpine yak meat: Nutritional assessment and structural-functional characterization of myoglobin, with emphasis on the inhibitory effect of carnosine on its pseudoperoxidase activity

Yak meat is emerging as an alternative to beef in Europe due to its taste, texture, and nutritional balance. Here, we report the European Alpine yak meat nutritional profile and the characterization of yak myoglobin (Mb), the haemoprotein responsible for meat colour and pro-oxidative processes. Nutritional analysis (macronutrients, amino acid composition, and fatty acid profile) confirmed high-quality proteins rich in essential amino acids, carnosine (~66.8 mg/100 g meat), anserine (~28.7 mg/100 g meat) and an optimal linoleic acid to α-linolenic acid ratio (10:1). Mb characterization included the determination of its primary structure, autoxidation rate, and pseudoperoxidase activity under increasing carnosine concentrations. Intriguingly, carnosine enhanced Mb autoxidation, while inhibiting metMb pseudoperoxidase activity through a mixed-type inhibition mechanism (Kᵢ = 1.81 μM). This dual behaviour highlights an indirect antioxidant mechanism for carnosine, providing the meat industry with molecular strategies to optimize packaging, extend shelf-life, and prevent metMb-catalysed oxidative deterioration during meat storage.