Effects of carcass weight and muscle on texture, structure and myofibre characteristics of wild boar meat

Texture, histology and muscle fibre characteristic of selected muscles: m. quadriceps femoris (QF), m. biceps femoris (BF), and m. semimembranosus (SM) of wild boars of different carcass weight (20 ± 2 and 60 ± 3 kg SD) were compared. Muscle texture (hardness, cohesiveness, springiness, chewiness) was determined with the double penetration test performed with the Instron 1140 apparatus. Structural elements (muscle fibre cross-section area, perimysium and endomysium thickness) and percentage of myofibres of each type: I (slow oxidative), IIA (fast oxidative-glycolytic) and IIB (fast glycolytic) per muscle fibre bundle, were measured in muscle samples using a computer image analysis program. The young wild boar muscles showed significantly lower values for the textural parameters (p < 0.05). The muscle fibre cross-sectional areas of the juvenile wild boar muscles were significantly lower and the perimysium and endomysium thinner (p < 0.05) than those in the old wild boar meat, while the percentage of type IIB fibres was higher. Of all the wild boar muscles tested, the highest hardness and chewiness values were found in BF which, at the same time, showed the highest fibre cross-sectional area and the thickest perimysium and endomysium. The highest percentage of I and IIA fibre types was typical of BF and SM either in young or in old wild boars with the lowest percentage of type I and the highest percentage of type IIB fibres being found in the QF. The results suggest that a higher hardness of wild boar muscles can be connected with a thicker perimysium and endomysium, fibres of higher cross-sectional area and probably a higher content of red fibres (type I).