Unpacking our tuna fishery process: from source to plate

The Cape Town tuna fishery presents several challenges: high running costs of vessels, poor weather, and long days with often little to show for the effort. Given the seasonality of tuna, minimal weather windows for fishing, and the unpredictability of this fishery, the focus at Cape Fish is to handle our tuna with great care, from the source all the way to your plate.

Here is a snapshot view of our process.

Up at dawn to head out to the deep-water canyon – Cape Town’s underwater “Table Mountain” where ocean currents create warm water upwelling and shoals of baitfish for the tuna to chase – the commercial ski boats run a 1-to 2-day operation. Depending on weather and the location of the fish, boats need a minimum of 2 hours to reach the canyon, and then it becomes a case of searching for the elusive fish.

Local knowledge, sonar scanning electronics, diving birds feeding on bait fish, combined with trawling lures are all tools at the disposal of the competent skippers, ensuring that they have the best chance of success.

Once the fish are located and catching starts, it’s up to the crew to manage the chaos and ensure the fish is landed as quickly as possible. Once the fish is caught, the tuna is bled and reamed: a process whereby the nerves are severed with a rod down the spine. This ensures that the adrenaline stops pumping, resulting in a firmer, more consistent loin of tuna.

Bleeding fish as soon as it’s caught is crucial to preserve the quality of the meat. This makes for a firm, and consistently textured and coloured tuna loin. The stress that a fish undergoes when it is reeled in causes lactic acid to build up in the muscle if it is pulled too hard. Furthermore, the excess blood in the fish, if not bled properly, can cause blood spotting through the meat. So, the sooner the fish is bled, reamed and gutted, the better-quality meat you’ll have.

Tuna have an extremely high metabolic rate, which means that the flesh can be quite warm. This will lead to spoilage if not dealt with accordingly, by lowering the temperature to just above freezing. This is crucial to preserve the freshness and quality of the fish. The best way to do this is to create a slurry on board the vessel: essentially a mush of ice and water. Tuna sink into the slurry, and after 10 to 12 hours this brings the core temperature down to 1 ̊C.

At Cape Fish, we take this to the next level and ensure that all of the fish we offload goes directly into slurries in our truck load bins, extending the period of complete chill and ensuring quality is kept as prime as possible from the landing sites through to our Paarden Eiland facility. These slurry tubs are then offloaded directly into our walk-in chillers to minimise handling, until the fish are pulled out for grading and processing. Carcasses are then graded by removing a section of the tail and taking a core sample. The higher the quality of the fish, the better the return.

We’ve structured our business to individually offer what each customers’ quality and price requirements are. This is unique to us within the local market and has helped build our name within the tuna industry.

Cape Fish has trained processors to ensure that there is minimal loss and wastage when breaking down the fish into fillets. Orders are assigned, thoughtfully packed to our customers’ requirements, and delivered with great care.

Nothing goes to waste here, as tuna carcasses are scraped to remove any excess meat. This excess meat is then packed and sold as “yellowfin tuna fish cake meat” or in our new brand of YAP treats for dogs and cats.