Effects of fishing gear on quality – The SEAQUID-EFF project 01/10/2013 Fishing gear and effective catch handling workshop 2013 Daphné Deloof Karen Bekaert, Johan Robbens Institute for Agricultural and Fisheries Research Animal Sciences Unit Agriculture and Fisheries Policy Area

Aim of the study 2  To compare the beam trawl, otter trawl and gillnets and entangling nets trawl in terms of quality of whiting and sole entangling nets trawl in terms of quality of whiting and sole  Sequid technology: objective alternative for QIM?

Aim of the study 3  Convincing the ship owners and their national association to turn away from the beam trawl in order to switch to turn away from the beam trawl in order to switch to an alternative methods an alternative methods  Improving the image and sustainability of the Belgian fleet, dominated by beam trawlers dominated by beam trawlers

Materials and methods 4  2011 : data collection on commercial ships (spring;summer;autumn/winter)  Analysis on board of commercial ships:  Initial muscle pH  Onset of rigor mortis  External damages – Injury Index Method (IIM)  Mortality rate  Analysis in the lab by shelf life study:  QIM  TVB-N

pH and rigor mortis in sole 5 pHRigor mortis gill & ent. otter trawl beam trawl Otter Beam Gill & ent

pH and rigor mortis in whiting 6 pHRigor mortis gill & ent. otter trawl beam trawl Otter Beam Gill & ent

Injuries 7 gill & ent. otter trawl beam trawl sole gill & ent. otter trawl beam trawl whiting

Mortality 8 sole whiting Otter trawl9%7% Beam trawl60%100% Gill & ent.nets15%100%

TVB-N and QIM (shelf life studies) 9

10

Conclusions 11  Sole :  Gill& ent.nets trawling is less stressful than beam and otter trawling  Less injuries with gill& ent.nets trawl, followed by beam trawl  Few mortality with otter trawl and gill & ent. nets trawl  Shelf life beam trawl < shelf life otter trawl < shelf life gill&ent.nets  Whiting :  Gill& ent.nets trawling is less stressful  Significant more injuries with otter trawl  Few mortality with otter trawl  Shelf life: no significant difference between beam & otter trawl Changing trawling methods promotes better quality and contributes to more sustainable fisheries

Sequid device: principle 12 XXXXXXXX  Objective alternative for QIM? (fish auction/ evaluation of catching methods in terms of fish quality)  Tested species: sole and plaice  Technology: diëlectric spectroscopy  TDR-measurements

Sequid device: principle 13 Sequid device : TDR measurement => Statistical PCA analysis Fourier transformation

Sequid device: results 14 MeasurementsRMSE (sole)MeasurementsRMSE (plaice) Dark skin side2.3 days Dark skin side2.1 days White skin side2.1 daysWhite skin side1.7 days Deskinned1.5 daysDeskinned- Fillets1.4 daysFillets1.6 days

Sequid device: conclusions 15  R²: 70% → 82%  RMSE with skin > RMSE deskinned RMSE dark skin > RMSE white skin > RMSE fillet  Experiments: tagged samples => reality = more complex!  Need for optimization of hard- and software for sequid device