Smart by Design

Stunner Why do fish need to be stunned before slaughter? Why use electricity? Do the fish recover? What about carcass quality? Will it work in any type of water? What is the rate at which the system works? Will I have to fiddle with knobs and dials? Is it safe for humans? Can the stunner be used for other species of fish?

FAQ's Stunner

Why do fish need to be stunned before slaughter?

In the UK all farmed land animals are, by law, humanely stunned before they are slaughtered in order to reduce any stress and eliminate pain to the animal by the process.  This legislation currently does not extend to fish, yet it has been proven that fish, like land animals, also feel pain, hence the need for stunning.

Why use electricity?

When correctly applied, electrical stunning produces (as near as can be judged) instant insensibility to fish. Ace Aquatec stunners are designed to be humane whatever the fish size or orientation, vigilance of the operator or quantity presented to the machine. Hence it can be argued that electrical slaughter can be the least stressful slaughter method and, with careful design, the fastest and most reliable method.

Do the fish recover?

Fish will recover from a short exposure to electricity consequently it is critical to ensure that the fish are exposed for the recommended treatment time and their subsequent processing ensures that they never recover consciousness.  Ace Aquatec works alongside the scientists and the farming community to ensure that this is so.

What about carcass quality?

Carcass quality of electrically stunned fish remains an issue for some species. Whilst Ace Aquatec machines have eliminated gaping flesh and broken vertebrae a small percentage of fish show blood spotting. Blood spotting is only apparent in the cut fillet. It does not affect the taste and is invisible if the fish is cooked but looks less appealing to the eye. Commercially this quality issue is offset by quality improvements such as low gaping, less scale loss and improved appearance of the overall fish.

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Will it work in any type of water?

Fish can be humanely stunned in virtually any type of water. However the voltage and current used is dependent on the water conductivity.  All Ace Aquatec stunners measure the water conductivity and adjust the voltage to deliver a humane stun but they are limited to specific conductivity ranges.

What is the rate at which the system works?

Ace Aquatec stunners are designed for commercial operation.  Typically this is 6 Tonnes per hour but can be up to 12 tonnes an hour.

Will I have to fiddle with knobs and dials?

Once installed Ace Aquatec stunners are fully automatic, switch on and press the start button when you want to harvest.

Is it safe for humans?

Every effort has been made to make Ace Aquatec Stunners safe for operators and bystanders alike. The systems have a number of in-built safety features that protect human operators even when they ignore safety instructions, however it must be remembered that all mains powered equipment has the potential to harm humans.

Can the stunner be used for other species of fish?

Although the Pipeline stunner is specific to portion sized trout the 2nd generation (HS2) is more versatile. Trial harvests of sea-bass, sea-bream, tilapia and eel have been demonstrated using 6" machines. The large 12" machines are currently harvesting salmon and can be adapted for cod and large trout. We expect this list to grow in the coming years.

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