If we believe the more extreme environmental pressure groups, the world’s oceans are becoming so depleted of fish that there will soon be nothing left to catch. However, despite continuous arguments between scientists and fishermen on what can be caught, it is now obvious that some fish stocks are seriously run down and the situation is becoming worse.
It is therefore imperative to obtain the maximum value for the fish that are caught. And to do so means taking a long hard look at material commonly regarded as 'waste'.
A former top European pig processor used to state: "We use all of the pig, nothing is wasted apart from the squeal". And it was true; every part of the animal was used in one product form or another, mostly for direct human consumption
Unfortunately the same cannot be said of the fish industry. Too often less than 50% of a fish will be eaten, whereas the rest will be reduced to fishmeal at best; and this process is often not possible to carry out at sea. So, what does happen to those parts of the fish that are not used for products directly sold to consumers?
Fish livers are often kept for their oil. Fish oil has become a very valuable product in its own right. Shelves in health food shops, and even in supermarkets, are full of supplements for improving human health, and fish oil capsules are claimed to maintain the suppleness and flexibility of joints.
Health food supplements also include vitamins and minerals, and fish is an extremely important source of both – in fact vitamin D is said to be the next most important aid to human health found in fish after omega 3 fatty acids. Similarly in this vein, fish bones could be used to provide calcium for health food supplements.
Apart from fish oil, it may not yet be commercially viable to manufacture health supplements from fish 'waste' produced at sea, but more basic products could be considered.
Machines which separate out the bones from fillet off-cuts, even fish skeletons, are now in common usage. Some of this recovered flesh will be dark in colour, but even so it can be used for the manufacture of products ranging from burgers and sausages to pet food.
Lighter coloured minced flesh is used for fish fingers and patties, while manufacturers of fish stocks and soups also need good quality fish flesh for their products.
On a more basic level, fish heads are a valuable source of food in some countries so could be kept for export.
Away from food products, fish skins can be used to produce leather and in Iceland garments, including bikinis, have been made from this material, whereas fish leather purses, wallets, belts and briefcases have been on sale at the International Boston Seafood Show.
These are just a few of the many possibilities for utilising more of the fish we catch, and some may not be suitable for at-sea processing. However, what may seem fanciful at this point in time may well turn out to be a financial lifeline in the future.
