The Composition and Production of Fish Feeds

Composition of Fish Feeds:

Fish feeds, like other animal feeds, can be divided into six main compounds :(1) water, (2) protein, (3) fat, (4) ash, (5) crude fiber, and (6) nitrogen-free extract (NFE). The main features of fish feed are protein and fat levels. The protein in the diet is mainly used for the accumulation of tissues, fat is the main source of energy and the increase of adipose tissue. The amount of carbohydrates in fish feed is usually low because fish, especially carnivorous fish, are less able to digest carbohydrates. Therefore, the energy in the diet must come from fats which have higher energy density than carbohydrates. For this reason, the fish feed is more concentrated and therefore has higher protein levels (up to about 40-45%) and energy density than the feed of farm animals on land. The digestible protein/digestible energy ratio is an important feature of a fish feed and, as a rule of thumb, should more or less resemble the protein/energy ratio of the growing fish itself. In this way, maximum retention of dietary protein (an expensive component of fish feed) is achieved.

Ingredients of Fish Feeds:

Fish feed is made up of various ingredients. Fish meal and oil have traditionally been the main ingredients in fish feed, especially for carnivorous fish, but now other ingredients are also used from plant and (land) animal sources. Food industry can be used as soy, peas and rapeseed protein, animal protein and fat ingredients. These ingredients can be used as a source of protein or fat. About 50% of the protein in fish feed comes from sources other than fish meal without affecting the growth performance.

Production of Fish Feeds:

Fish feed is produced by extrusion. The extrusion process involves high temperature and pressure, and the starch in the feed is gelatinized. This gelatinization or pressure cooking of starch produces particles with a strong structure. Extrusion technology allows the production of particles of various sizes and shapes that are water-stable and dust-free. In addition, the physical properties of the pellet can be controlled and floating and sinking pellet can be produced. Finally, the extrusion process allows a large amount of fat vacuum coating of the granule and the production of a feed with a high fat content.

Fish Feed Types

We classified feed types in two groups: Moisture Feeds and Dry Feeds (Pellet and Extruder Feeds)
1. Moisture Feeds Advantages

  • The main principle is grind and mix and then feed the fish;
  • Most important advantage of the feed is to be cheaper than the other feed types;
  • It does not require any mechanization.

2. Dry Feeds Advantages

  • Nutritional content of the feed is guaranteed (you can exactly know the nutritional level of the feed);
  • there is no change according to the season of the year;
  • You can buy it whenever you want from fish feed plants;
  • It is easy to store the feed.

Machines Used in Fish Feed Production

Feed Hammer Mill
Feed hammer mill is used to crush raw materials. Outstanding features include advanced design, good durability and stable performance.

Grain Powder Mixer
Mixers are widely used for mixing grain powder in fish feed production line. Our mixer design is based on a u-shaped tank with dual shafts and blades that extend the length of the tank so that the different components are evenly mixed in the shortest possible time (CV < 5%).

Fish Feed Pellet Extruder
There are two types of fish feed extruders: dry type and wet type. The dry fish feed extruder does not require a steam boiler, while the wet type is designed as a regulator and requires a steam boiler (you can purchase one at your location).

Feed Pellet Dryer
The dryer has multiple mesh layer designs (3,5,7 layers are optional). Can control the speed of net belt to adjust the drying time. It is highly automated and has advanced equipment for loading and placing materials.

Feed Pellet Packing Machine
The automatic packing machine has simple structure, accurate weighing and reliable operation. It can quickly weigh and package feed pellets. The system is suitable for granular materials and powder materials with good fluidity.