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Salmon: A Guide to Handling and Quality

5 October 2015, at 1:00am

Wild salmon that are damaged due to poor handling diminish the reputation of the entire fishery. Supplying the market with a consistent high quality product is vital for the wild salmon industry to thrive. The aim of this guide from the Irish Sea Fisheries Board (BIM) is to provide practical and contemporary guidelines on the handling and quality of wild salmon.

It is therefore important to handle the fish carefully and chill it quickly.

Following these 5 simple steps will help you improve your handling.

1 Removing from the net

Some net markings will occur but removing salmon roughly from the net, particularly against the direction of the scales, can cause bruising and heavy scale loss. In addition pulling the fish by the tail can dislocate the backbone and cause blood to seep into the fillet. Make sure that whenever the salmon are handled they are pulled or held by the head and not by the tail.

When using a net hauler fish must not be allowed to pass through the rollers. Remove fish before they reach the hauler or keep the section of net with the fish clear of the mechanism. Otherwise bruising and backbone damage could ruin the fillet.

Removing from the net - Don't pull fish by the tailRemoving from the net - Careful removal of the catch

2 Stunning

Fish should be stunned as quickly as possible after being brought on board. If fish are not stunned scale loss and bruising are inevitable as fish thrash around on the deck. It will also make removal of the fish from the net easier.

Stunning is particularly important when draft netting as fish can be badly damaged struggling on a rough shore. To avoid this the net should be hauled in on an area clear of rocks and other obstructions and the fish removed from the net as quickly as possible and stunned. Salmon should be stunned by a blow on the snout, not on the back of the head or shoulders.

A prolonged struggle causes excessive scale loss and also reduces quality as the longer a fish struggles before it is killed, the higher the risk of bruising, gaping of the fillet and mushy flesh.

Excessive scale loss is an indication that the fish could have internal bruising!

Stunning - Fish should be removed from a draft net as quickly as possibleStunning - Heavy scale loss often means there is internal bruising

3 Bleeding

The highest quality fish are bled as this minimises blood traces in the fillet. Stunned fish are ideal for bleeding as the heart will pump the blood from the fish and it dies quickly and painlessly. To do this at least three of the gill arches are cut. Only the gill arches should be cut through and care must be taken not to damage the collar area. The blood should be washed away by placing the fish in a water bin with the deck hose running for no more than 10 minutes as otherwise the gill colour will fade.

Bled salmon is prized for smoking!

Bleeding - Cutting the gill archesBleeding - Wash away the blood

4 Gutting

Gutting should only be carried out once bleeding is complete. Extreme care should be taken, as careless gutting is worse than not gutting at all.

Fish must be gutted along the centre line from the vent to the base of the pectoral fins or about 3cm behind the “V” of the neck.

Guts should be removed intact by cutting through them where they attach to the back of the head. They can then be removed intact by firmly pulling them up and back towards the tail of the fish. To remove blood in the kidney and associated veins, the back of a spoon must be used as it is blunt and rounded and will not damage the fillet. The kidney, a deep red mass that runs along the backbone, should be slit open from head to tail with the tip of a knife and then, using the back of the spoon, scraped out and removed by gently sliding the spoon along the backbone.

Fish should be washed thoroughly, ensuring there are no traces of blood or guts left in the gut cavity.

Tidy gutting with no damage to the cavity walls is essential!

Step 1 - Insert the knifeStep 2 - Cut towards the head

Step 3 - Remove the gut materialStep 4 - Remove the kidney

5 Boxing and icing

Low temperatures slow down the rate of spoilage. Temperature management has a major influence on salmon quality. Immediate chilling of the catch is essential. If the boat has no insulated ice hold, sealed insulated bins kept on deck are essential for icing and holding salmon at sea. Wild salmon should be boxed correctly to maintain quality.

Round salmon should be placed on a layer of ice, on their back, each layer in one direction, with the next layer on their back in the opposite direction.

Gutted salmon should be placed on a layer of ice, cavity down, with each layer facing in one direction. Ice should be placed in the gut cavity but only sufficient to maintain the natural shape of the salmon.

Chilled salmon to 2ºC maximises quality!

Boxing and icing qualityTemperature profile recorded for salmon iced at sea

6 Vessel hygiene

A ‘clean as you go’ approach should be adopted. Knives and oilskins should be kept clean at all times. At the end of every day’s fishing wash down the deck, hold, insulated bins and any boxes used with clean seawater and a stiff bristled brush. Detergent should be used if items are particularly dirty.

The boat and all equipment should be thoroughly cleaned using detergent and food grade disinfectant at the end of every week. Rinse afterwards with clean seawater to remove any residue.

When finished for the day ensure everything is properly washed down and tidily stowedA little care every day keeps everything clean and hygienic

7 Ensuring premium quality!

Eyes Normal in appearance, bright and clear
Gills 1(a), 1(b) Good colour – uniformly red, easily
Fish firm Resilient when subjected to finger
Odour Seafresh or odourless
Good skin condition Firm, bright, shiny, clear mucus, no
desiccation, no predator damage (no
open wounds on the flesh, tail intact)
Net damage 2(a), 2(b) No deep indentation on the dorsal
surface further than half way down the
pectoral fin
Scale loss 3(a), 3(b) No more than 30% scale loss
Gills Good ColourGills Bad Colour
Net damage GoodNet damage Bad
Scale loss GoodScale loss Bad

7 Ensuring premium quality! (contd.)

Consequences... Tell-tale signs!

Heavy net damage bruisingLight bruising due to net markings
Markings near the pectoral finNon-bled salmon
Bruising before and after smoking
Not iced, open to the elements, looks awful and the result
October 2015

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