Avaliação de métodos de abate sobre a qualidade da carne de matrinxã (Brycon cephalus), armazenados em gelo

Abstract

DEDICATÓRIA Dedico este trabalho aos meus queridos pais Wilson e MarleneSince fish is the most traded feeding commodity internationally, its quality control and security are extremely important. That goes beyond meat quality; it regards ethical aspects of animal welfare. In Brazil this aspect of fish production has only recently received importance, even though it is common in poultry and mammal productions.Therefore, one of the most critical steps to keep fish quality is the slaughter, because the stress caused by this process directly affects rigor mortis leading to low meat quality and short display life of the final product. For that reason, the objective of this study was to evaluate the influence of different slaughter methods on meat quality of matrinxã, Brycon cephalus, and also to study its stability in cold storage during 18 days. 90 matrinxã fish with average weight 535.10 + 121.36 g and average size 32.93 + 2.35 cm were used in three trials: i) slaughter by electric shock, ii) asphyxia by CO 2 saturation, iii) thermal shock using water-ice solution (1:1). After the slaughter process the fish were maintained refrigerated at 4ºC during 18 days and the rigor mortis, eye and muscular pH index, total volatile basic nitrogen (TVBN), filet muscular contraction, color (L*, a* and b*), instrumental texture and sensory analysis in accordance with the European Community were evaluated. Samples were taken after the animals' death (time 0), at 3 and 5 hours and on days 1, 4, 7, 12 and 18 of storage. Data from physical-chemical analysis were submitted to ANOVA and when significant difference (P<0.05) was found means were compared by the Tukey test.Sensory evaluation results were submitted to Wilcoxon test. Red color (a*) was more intense for the fish slaughtered by electrical shock (5.1694) when compared to the ones slaughtered by asphyxia with CO 2 saturation (0.8639) and water-ice solution (1.035). On the contrary, for filet luminosity (L*) the inverse happened and electric shock occasioned lower mean in comparison to the slaughter methods by CO 2 saturation and thermal shock (56.1412; 61.8439; 60.9767, respectively minutes). In the evaluation of ATP degradation and its derivatives showed that the electrical shock maintains higher levels of ATP, when compared to other treatments throughout the sampling period, helping to maintain freshness.Therefore, it can be concluded that the electrical shock slaughter method may be a good option to slaughter matrinxã fish, since it causes rapid death and minimum suffering.

Effect of different periods of pre-slaughter stress on the quality of the Nile tilapia meat

“…Dne explanation for this may have been established by the chronic stress state in the sampled fish, caused among other things by the low quality water and high stocking densities. However, Vargas (2011) mentions that the intensification of fish meat acidity occurs after approximately 56 hours of storage, a result similar to that found by this research, in which the lowest pH was obtained exactly between 48 and 72 hours.…”

O Mapeamento De Uma Cadeia Extrativista Na Amazônia: Arapaima Gigas Em Reservas De Desenvolvimento Sustentável

“…Há algumas décadas, o abate de animais era considerado operação tecnológica de baixo nível científico até observarem que os eventos que se sucediam desde a propriedade rural até o abate, influenciavam a qualidade da carne (Vargas, 2011). Atualmente, os aspectos do funcionamento físico, fisiológico e comportamental são de relevância fundamental para a avaliação de bem-estar no manuseio de peixes.…”