Handling of fish on-board Icelandic International Development Agency (ICEIDA) Iceland United Nations University Fisheries Training Programme (UNU-FTP) Iceland National Aquatic Resources Research and Development Agency (NARA) Sri Lanka Department of Fisheries and Aquatic Resources (DFAR) Sri Lanka Quality and safety issues in fish handling A course in quality and safety management in fishery harbours in Sri Lanka NARA, DFAR, ICEIDA and UNU-FTP

Content Video about handling on-board Current practices and improvements Handling of tuna on-board

Learning objectives After this lecture the participants will have: an overview of the situation in Sri Lanka regarding handling on board ideas on how to improve the situation

Video Handling of fish on-board - UK -

Current practices Fish is put in hold at sea temperature Fish is stored loose in hold (pressure on fish in lower layers) Fish is cooled with crushed block ice or flake ice Handling time on deck is long (in heat) Gutting and bleeding usually not practised

Video Storing fish in the hold

Possible improvements Put fish into ice slurry in an insulated tub after catch for cooling down fast for bleeding Put cold fish into boxes in hold easier handling less pressure on lower layers possible to use day markings

Manual transport equipment Hand-drawn truck Sack or case truck Hand pallet truck

Cooling rates in the center of cod - comparison of flake ice and liquid ice Temp. (°C) Time (hours) Flake ice Ice slurry

Cooling /keeping cool Ice slurry is good for cooling fish down quickly compleatly surrounds the fish good heat transfer Flake ice is good for keeping fish cool keeps fish moist while melting blood water and slime is washed off This may require less ice than the current practices and give much better quality fish

Video Small boat in Reykjavik harbour

PRE-HANDLING AND HOLDING METHODS FOR OCEAN TUNA

Content of this lecture The importance of handling and storage of ocean tuna Diagram of handling and storage of raw material

Yellow fin tuna Big eye tuna COMMON SPECIES OF OCEAN TUNA IN SRI LANKA

The importance of pre-handling and holding of ocean tuna Assure good quality of raw material Prevention of histamine formation

Maintain quality of raw ocean tuna If catching, pre- handling and holding is not done properly Appearance will be changed Colour and flavour of flesh can be changed

The importance of handling and holding of ocean tuna (Continued) Histamine Histidine Histamine Histidine decacboxylaza

Catching, gaffing and landing  Killing  Bleeding  Gutting  Cleaning  On-board storage Diagram of HANDLING and holding of OCEAN TUNA

Always gaff the fish through the head. Use two gaffs for big fish, the second through the mouth It is advisable to lift the fish tail to help haul it on-board Carry out all subsequent handling on a foam pad CATCHING, GAFFING AND LANDING THE FISH

KILLING THE NEWLY- LANDED TUNA Once aboard, the fish should be killed immediately

Bleeding Bleeding the tuna by making a cut in the side of the fish with a knife, five to ten centimeters behind the base of pectoral fin recess, on both sides of the fish. Blood should flow freely from these cuts.

The gutting of fish can bring about the following advantages: Make subsequent chilling more effective Make subsequent chilling more effective Remove undesirable digestive enzymes Remove undesirable digestive enzymes Prevent undesirable bacteria in the fish intestine from spreading Prevent undesirable bacteria in the fish intestine from spreading Avoid the penetration of parasites such as nematodes from the gut into the flesh Avoid the penetration of parasites such as nematodes from the gut into the flesh GUTTING OF FISH

Scrub the inside of the abdominal cavity without removing the white membrane which covers the backbone. Carefully rinse the fish, inside and outside. The fish is now ready to be placed in brine or ice. Cleaning of fish

ON-BOARD STORAGE Lower the internal temperature of the fish by placing it in chilled brine (a slurry of crushed ice and seawater). After the core temperature reaches 0°C, put the fish in ice and keep it there until arrival at port. It is recommended to use the two following staged procedure to obtain a top-quality fish (like in pre-handling of raw materials). Alternatively, the tuna can be iced directly to reduce temperature. However this method takes longer time

On-board storage

UNLOADING of fish The following rules are important during loading: Do not twist the fish when removing them from the ice. They should be held by the head rather than the tail. Handling the fish gently. Do not leave the fish too long in the open air or sunlight.

References 1.Training materials on catching and on-board handling of ocean tuna. Pacific Ocean Organisation. 2.INFOFISH (1999) 3. Hall, G.M (1997). Fish Processing Technology 4. Scombroid Poisoning. FDA (1999) 5.FDA (2003)