Respouso pós transporte em diferentes densidades sobre a qualidade da carne datilápia-do-nilo

Abstract

Transporting fish from farm to slaughter at high densities can cause stress, which negatively affects meat quality. Seeking to reduce this impact, post-transport rest can be a strategy to return to the initial homeostasis of the fish. The aim of this study was to evaluate the impacts of transport at medium and high density, combined with different post-transport rest times, on aspects of instrumental and sensory quality of Nile tilapia fillets. Fish (average weight 967, 975 ± 13,975 kg) were transported at two densities (250 and 500 kg/m³) for one hour, and after transport they were placed in water boxes and maintained for different resting times (0, 2, 4 and 6 hours). Filet yield, rigor mortis, pH, color, shear force, moisture, water holding capacity, weight loss from cooking, drip loss, texture and sensory profile analysis were performed. The longest pre-rigor mortis time was observed at 500 kg/m3 associated with 4 hours of rest, at 0 and 2 hours of rest. The density of 250 kg/m3 associated with 4 hours of rest provided fillets with greater intensities of red and yellow. The highest cooking weight loss was found at 500 kg/m3 associated with no post-transport rest time. In general, the high transport density provided fillets with higher pH, lower red and yellow intensities, greater weight loss by cooking and greater drip loss. Resting for 4 and 6 h provided fish with longer pre-rigor mortis time, lower luminosity, higher red intensity and greater firmness. Fish submitted to six hours of post-transportation rest showed fillets with greater water retention capacity and lower drip loss. The treatments did not affect the yield, moisture, texture profile and sensory attributes of fillets. It is concluded that the high transport density negatively affects the quality of Nile tilapia meat, however post-transport rest times of 4 to 6 hours can improve quality, reducing pallor, water loss and increasing the firmness of the fillets.