Fish products and Byproducts Technology

Unit 9 - Fish meal and fish oil

9.4. Raw materials used in fish meal
Virtually any fish or shellfish in the sea can be used to make fish meal, although there may be a few rare unexploited species which would produce a poisonous meal. The nutritional value of proteins from vertebrate fish differs little from one species to another; whole shellfish would however give a nutritionally poorer meal because of the low protein content of the shell. Most of the world’s fish meal is made from whole fish; the pelagic species are used most for this purpose. Where a fishery catches solely for the fish meal industry, it is known as an industrial fishery.
Countries with major industrial fisheries are Peru, Norway and South Africa. Some countries like the UK make fish meal from unsold fish and from offal that is the heads, skeletons and trimmings left over when the edible portions are cut off. Other countries like Denmark and Iceland use both industrial fish and processing waste. Fish meal made mainly from filleting offal usually has slightly lower protein content and a higher mineral content than meal made from whole fish, but a high proportion of small whole fish in the raw material can have the same effect.

Fish used for reduction to meal may be divided into three categories:

• fish caught for the sole purpose of fishmeal production
• by-catches from another fishery (by most fish-producing countries);
• fish off cuts and offal from the consumption industry.

A fishmeal industry requires a regular supply of raw material. When planning fishmeal factories, it is necessary to know the type of fish species available, the length of fishing season, the location of the fish, the catchability of the fish by different fishing gear and, if possible, the attainable catches per year for a continuous period.