Konferansebidrag og faglig presentasjon » Faglig foredrag
Short time live storage and pre-rigor processing of haddock
The 47th WEFTA Seafood R&D Conference; Dublin, 2017-10-09–2017-10-12
Haddock (Melanogrammus aeglefinus) caught with bottom trawl or Danish seine can have poor quality and are often payed less than line caught haddock. Soft muscle, fillet gaping and residual blood are typical quality challenges. Thus, Norwegian Seafood Research fund (FHF) has founded this project, to document how optimal handling can assure first-class fresh haddock. Haddock of commercial size (0.7-2.5 kg) were caught with Danish sein at 77-125 meter dept. The fish were pumped from the codend and into live storage tanks onboard the weasel (M/S Ballstadøy). Blood samples were taken from haddocks (n=10) to measure levels of lactate and glucose. Two control groups was taken; one group of haddock from the same catch were slaughtered and stored on ice and a second group was slaughtered and kept inn ice-slurry until delivery at the fish processing plants proximately 12-16 hour after capture. During landing, all death fish in the tank was registered. Live fish were stunned ether with electricity or by a blow to the head prior to slaughtering and pre-rigor fileting. The control groups were filleted 24 hour after capture (in rigor). A fillet index was applied to evaluating fillet gaping, color, bruises, texture damages and soft flesh. An instrumental hyperspectral imaging spectroscopy was used to measure residual blood in the fillet. The survival during transport were between 40 and 80% and factors e.g. haul size, weather condition, crowding, barotrauma and fatigue are influencing the mortality. For live haddock, there is a significant improvement in the levels of bleeding, as well as fillet color and gaping, compared to the control groups. The results shows that gentle handling, short time live storage and pre-rigor processing of haddock is possible.