Fish Products and Byproducts Technology

Unit 8 - Fish Protein Hydrolysate

8.4. Proximate composition and Nutritional value

• Moisture- 1-8%
• Protein-81-93%
• Fat- 0-5%
• Ash-3-8%

Evaluation of hydrolysates using nitrogen balance studies and growth experiments on rats established high nutritional values for the product.
The protein efficiency ratio (PER) of fish protein hydrolysates depends on the extent of enzymatic digestion and its amino acid profile. Usually the PER value is from 2-3.
The fish protein hydrolysates are found to have the essential and non essential amino acid in a defined proportion based on the hydrolysis condition.

Advantages

• No racemization of amino acids
• Control over the hydrolysis condition
• Utilization of secondary products from fish and underutilized fishes
• Resultant hydrolysate possess improved physico-chemical, functional and bioactive properties

Disadvantage

• High cost of enzymes
• Difficulty in controlling the extent the of hydrolysis that can result in heterogeneous products of varying molecular weight sizes
• Low yield
• Need to inactivate the enzymes add to processing cost
• Enzymes cannot be reused