Pre-Slaughter Stunning Methods Influence the Meat Quality of IArapaima gigas/I Fillets

• Published in: Animals (Basel) 2024-04, Vol.14 (8)
• Main Authors: Braitenbach Cavali, Jucilene, Vargas Baldi, Sheyla Cristina, Coutinho Marques Rocha, Ana Sabrina, Eloy da Silva, Erica, Taveira Nunes, Carla, Soares, Emerson Carlos, de Vargas Schons, Sandro, Zanella, Renato, Bianchini Pontuschka, Rute, Vieira Dantas Filho, Jerônimo
• Format: Article
• Language: English
• Subjects: Analysis; Aquaculture industry; Blood sugar; Mariculture; Methods
• ISSN: 2076-2615; 2076-2615
• DOI: 10.3390/ani14081155

It was confirmed that electronarcosis (EE) is a better method of pre-slaughter stunning for the meat quality of Arapaima gigas fillets from fish farming; the other methods are ice asphyxiation (IA), air asphyxiation (AA) and hypothermia followed by bleeding (HB), which showed fewer interesting results. Data were obtained from a pH analysis, rigor mortis index (RI), water activity (Aw), instrumental texture, blood glucose and instrumental colourimetry. During the study, for up to 15 days of refrigerated storage, the methods provided pH values below 6.0. EE resulted in better texture assignments in the fillets. The blood glucose values indicate that the fish subjected to EE were less stressed. Regarding instrumental colourimetry, the fillets submitted to EE and HB showed greater luminosity, those subjected to AA exhibited greater red-green colour intensity and those subjected to EE showed greater yellow-blue colour intensity. Therefore, the fish did not suffer stress with electronarcosis, and the fillets showed better preservation, juiciness and tenderness. The aim of this study was to evaluate the influence of different stunning methods on the meat quality of Arapaima gigas fillets from fish farming. A total of 48 specimens of A. gigas in the weight class 11.1 to 14.0 kg were investigated; these fish were subjected to different stunning methods for slaughter: ice asphyxia (IA), air asphyxia (AA), electronarcosis (EE) and hypothermia followed by bleeding (HB). Then, data were obtained from the analysis of pH, rigor mortis index (RI), water activity (Aw), instrumental texture (compression strength, firmness and adhesiveness) and blood glucose and via instrumental colourimetry. During the study, for up to 15 days of refrigerated storage, the methods provided pH values below 6.0. A. gigas submitted to EE and HB remained longer in the pre-rigor status. In addition, they expressed lower percentages of Aw. The EE method resulted in better texture assignments in the fillets. The blood glucose values indicated that the fish subjected to EE were less stressed. Concerning instrumental colourimetry, the fillets submitted to EE and HB showed greater luminosity; the fillets subjected to AA showed greater red-green colour intensity, while the fillets subjected to EE showed greater yellow-blue colour intensity. Therefore, the fish did not suffer stress with electronarcosis, and the fillets showed better preservation, juiciness, and tenderness.