Fishmeal (FM) is a generic term used for nutrient-rich feed ingredient used in the diets of livestock. To produce 1 ton of fishmeal, it is estimated to require 4 to 5 tons of whole fish. The fishes that are caught are considered industrial as most of them are caught for the sole purpose of fishmeal and fish oil production.
Traditionally, fishmeal has been the main source of protein in both agriculture and aquafeed industries because of its excellent source of essential fatty acids (EFAs), its high proteins, minerals and vitamins content and its digestible energy.
Most commercial FM is made from predominantly small, oily and bony fishes that are considered not suitable for human consumption directly. To produce fishmeal, there are several steps involved, but the main principle involves separation of the oil and water from the solids.
The fish moves through a screw conveyor cylinder equipped with a steam jacket, which coagulates the tissue proteins in the process.
Once it is cooked, the fish is pressed to remove the liquor produced from cooking it. The solid residue that remains is called the presscake. On the other hand, the liquor is centrifuged to separate the oil from the suspended solids and is sent to further processing to produce fish oil. The concentrated “stickwater” produced from treating the liquor can be optionally added back to the presscake, therefore one can choose to purchase between “whole” meal or just “presscake” meal.
Going back to the presscake, it is then dried using either a direct or indirect drying, so that the moisture content is low enough to lengthen its shelf life and prevent growth of mold and bacteria.
Grinding and packaging
Once the fishmeal is dried enough, it is grounded and screened to the correct particle size to be stored in silos or packed into bags, ready to be delivered to many companies across the world.
Source of protein, minerals and vitamins for livestock such as cattle, chickens, pigs and horse. Normally, fishmeal contains around 60 to 70% crude protein by weight. It also promotes fast growth and reduced feeding cost whilst providing synergistic effects. Sometimes, it is also used as an organic fertilizer.
Crabs, shrimp, fish and many other aquatic creatures are in need of fishmeal as well to promote fast growth.