Evaluation of post mortem flesh quality attributes in common carp (Cyprinus carpio L.) slaughtered by exsanguination and hypothermia methods

In this study carps slaughtered by exsanguination and hypothermia and post mortem flesh quality attributes in order to determine effects of pre mortem activity during slaughtering on fish flesh quality evaluated. Results showed different slaughtering methods significantly affected on flesh quality (P<0. 05). Maximal rigor index was observed after 12 hours post mortem in hypothermia group، however rigor index reached maximum at 3 and 9 h post mortem for the asphyxia and exsanguination groups. In overall during experiment period flesh pH in hypothermia group was higher than other groups. Flesh pH in hypothermia، exsanguination and asphyxia was 6. 53، 6. 34 and 6. 32 respectively. In this study refraction index ranged 1. 36-4. 84. Drip loss had significantly differences in experimental groups (P<0. 05). Drip loss (%) in hypothermia، exsanguination and asphyxia groups 72 h post mortem was 1. 73، 1. 84 and 1. 86 respectively. Flesh colorimetric analysis showed no significantly differences among experimental groups (P>0. 05). Hypothermia، exsanguination and asphyxia slaughtering procedures significantly affected on colorimetric skin color parameters during time and in experimental groups (P<0. 05). During trial period skin L*، b* and Hue* increased and skin a* decreased. Chroma* showed no considerable differences during trial. Results of this work showed slaughtering fish by hypothermia had higher flesh quality in comparison to other groups.