Characterization of rigor mortis process and meat tenderness in Santa Inês and F1 Santa Inês x Dorper lambs

Abstract

The development of rigor mortis process of butcher animal carcasses directly influencing the meat quality. The characteristics of rigor mortis process in ovine carcass during industrial chilling to obtain the chilled carcasses have been studied in other countries and in Brazil in Santa Ines sheep, but not yet established in F1 Dorper x Santa Inês. Thus, this research was designed to characterize the rigor mortis process of Semitendinosus and Triceps brachii muscles of ovine carcasses during the industrial chilling and meat tenderness, and the measurement of morphological traits: slaughter weight, withers height, croup height, body length, thorax perimeter and carcass yield. Ten intact male ovines Santa Inês and F1 Santa Inês x Dorperbreed were randomly assembled slaughtered at Campos dos Goytacazes, Rio de Janeiro. After exsanguination, were measured temperature, pH and sarcomere length at different times (4h; 6h; 8h; 10h; 12h; and 24h) and shear force or tenderness (48h) of Semitendinosus muscle. The chilling room temperature varied between 12.2°C (4h) a -0.5°C (24h), and the mean temperature of carcasses was 26.80°C and -0.20°C, respectively. The mean initial pH of Semitendinosus was 6.62 and final 5.64 and of Triceps brachii was 6.50 (4h) and 5.68 (24h). The maximum contraction of sarcomere of Semitendinosus occurred at 12th hour (1.50mm) after exsanguination whereas for the Triceps brachii,at the range of the 10th to 24th hours (1.53 to 1.57mm). Semitendinosus muscle shear force and tenderness was similar in lambs of Santa Ines breed and F1 Dorper x Santa Ines, demonstrating that the genetic group did not affect meat tenderness.