Fishmeal and fish oil are produced from harvesting stocks of fish for which there is little or no demand for human consumption and also from the use of trimmings left over from processing fish for food. The whole fish are mainly small bony oily and largely inedible such as anchovy, horse mackerel, menhaden, capelin and sandeel.  These fish store oil in their flesh.  Trimmings, which are also used, produce between 10% to 15% of world fishmeal.  This is produced from either white-fish which is low in oil (most of the oil is in the livers which are used for oil production e.g. cod liver oil) or trimmings from oily fish such as herring, mackerel etc.

Fishmeal is normally a brown powder/meal typically with 60% to 72% protein and 5% to 12% fat and 10% to 20% ash.  Producers can supply details of the type of raw material used and expected nutrient content.

During the processing fish oil is produced, without solvent extraction - it is pressed out of the cooked fish (see Production).  Fish oil is normally yellow/orange to dark brown in colour depending on the species of fish from which it is produced.  It is liquid above 10^oC but can start to solidify below this temperature.

Virtually all fishmeal is used as a high-protein ingredient in feed for farmed land animals and for farmed fish.

Fish oil is used mainly in feed for farmed fish but is also used to make capsules containing omega-3 fatty acids as human health supplements.

The Aquaculture Value Chain is one example of how the fishmeal and oil industry links with other businesses further down the food chain.