Fish Feed Binders
Fish binder is a type of ingredient used in making fish feed. It enhances the taste of food, prolongs the storage period and increases the high water retention capacity in food. It also prevents food wastage and increases food intolerance efficiency. It provides high strength capacity for pellet feeds. It also helps to keep the feed stable in water.
Feed binders can be divided into two main groups. e.g.
- Natural substances (marine and terrestrial vegetable extracts and animal extracts)
- Synthetic binders (synthetic chemicals)
Table: Common natural binders
Marine Plants Extracts
Terrestrial Plants extract
* Most commonly used: their inclusion level is 1-4% (except starch: 10-20%)
Common Artificial Binders
The most common synthetic binders used in fish and shrimp food are: Bentonites - 1-2% sodium or calcium are available as bentonites; Lignosulphonates - 1-4% lignosulphonate from Pulp Industries; Hemicelluloses - 1-2% hemicelluloses from Pulp Industries; Carboxymethycellulose: 0.5-2.0% and Starches-<3%.
Starch is the cheapest and most readily available binder for making pelleted food. Starch is obtained from different types of plants such as cassava, palm, rice, flour and maize. Binders are again of two types based on durability, viz
1. Short term water stability binders: Lignosulphonates, Hemicelluloses), and Carboxymethycellulose.
2. Long term water stability binders: Starch, alginate, seaweed extract, plant gum, chitosan and gelatin
Polymethylcarbamide / Basfin is an important specialized binder that binds proteins and carbohydrates. Such binders are not approved by the USFDA (United States Food and Drug Administration) because they are tasteless.
Urea formaldehyde/calcium sulphate mixture: It is also known as maxi-bond. Maxi-bond is a USFDA approved binder and has no harmful role. The allowable level of both Basfin and Maxi-bond is 0.5%.
Binders for moist/semi-moist feeds
Alginates are a type of binder used in moist / semi-moist foods. It usually attaches to food by producing gels. Occasionally calcium ions, vitamins, calcium sulphate, etc. are used to make food by producing gels. Ordinary salt or (Nacl) at the rate of 1% is also used to combine raw trash fish and moist food.
Antioxidants are a type of chemical produced in nature. Such ingredients are especially used to bind lipids or carbohydrates and to protect food from decay. Synthetic antioxidants are used to prevent the formation of toxic substances in food. Since natural antioxidant ingredients such as vitamins, ascorbic acid and alpha tocopherols are not long lasting in food, it cannot play a role in food preservation. Synthetic antioxidants that are used commercially are: BHT (Butylated Hydoxytoluene), BHA (Butylated Hydoxyanisole) and Ethoxyquin (ethoxyquin). Of these, BHA and BHT are approved for human diet and are occasionally used in the diet of other animals. Ethoxyquin is only used in fish food. The maximum dose approved by the USFDA for BHA and BHT is 2% and the recommended dose for ethoxyquin is 159 mg.
A variety of substances are used to protect food from decay. Such substances are commonly called preservatives. Such as sodium salt, potassium salt and propionic acid, benzoic acid, ascorbic acid are used as preservatives.
The use of antibiotics in fish feed has generally been discouraged. This is because the part of the antibiotic that remains in the body of the fish is harmful to humans. If it is to be used to prevent disease, then the required dose and time must be adhered to. In addition, regular use of antibiotics increases the immune system of the fish in the body.
Different types of natural and synthetic hormones are used in fish food. These are growth hormones, thyroid hormones, insulin, different types of sex hormones and so on. Synthetic androgens accelerate the growth and food intake of some fish, such as salmonids. However, there are some high temperature fish that avoid sexual androgens. The use of sex hormones has now spread in our country. This process is applied to the physical growth of fish such as Monosex Tilapia. These hormones are usually used in the larval stage.
A variety of antibiotics are used to protect fish food from fungal infections. In addition, such anti-microbial ingredients are used directly in unpolished foods. The following table lists the anti-microbial ingredients commonly used in artificial fish feed:
Table: List of anti-microbial ingredients used in artificial fish food
Benzoic acid, sodium benzoate
Propionic acid, calcium / sodium propionate
Methyl or propyl paraban
Na / K-sulphate, bisulfate and meta-bisulfate
The use of some of these antimicrobial agents is specific and the use of some of them is extensive and varied. Benzoate, paraben, propionate etc. are the most widely used antimicrobial ingredients. Potassium sorbate on the other hand controls the fungus in the pelleted diet.
To make fish food appealing to fish, a variety of substances are added to the food which help the food to have the right size, shape, firmness, tenderness, taste and float in water. Such food ingredients are mixed to increase the fish's appetite for food. There are some food ingredients that naturally carry food stimulating properties. Such foods are fish meal, fish oil, squid oil, shrimp meal, yeast hydrolase etc. There are also some synthetic chemicals that are used as food stimulants. Such as L-amino acids, betaine and some nucleotides (inosine) which are found in oysters, squid, shrimp and fish products and are widely used as food stimulants.
Miscellaneous Feed Stuffs
Miscellaneous food ingredients are used in fish food. But their value has not been fully determined even today. Some of these compound materials are called Non Conventional Feed Stuff. Sugarcane is used as a non-conventional ingredient for other animals. Such non-conventional feed stuffs are mainly marine weeds, sugarcane by-products, microbial proteins, algae, fertilizers and cellulose.