Preliminary approach on early post mortem stress and quality indexes changes in large size bluefin tuna (Thunnus thynnus)

Abstract

Bluefin tuna (Thunnus thynnus) is very appreciated on Japan and USA market for the preparation of sushi and sahimi. The market price of the fresh product can vary from 8 to 33 Euro/kg (gate farm/producers prices) according to size, shape, fat level, meat colour, consistency and freshness (absence of “hyake”), all parameters strictly connected to feeding quality and quantity, rearing and killing stress factors and refrigeration times and conditions after death. Excessive levels of stress during the slaughtering can affect meat quality, contributing to significantly decrease of tuna’s price. The present trial was carried out to evaluate the possible harvesting/slaughtering stress effect on reared bluefin tuna meat quality, starting from the examination of the most important stress and quality parameters changes during the early post mortem period.