Investigation of the biopotential of products of hydrolysis of waste from cutting the white-legged shrimp Penaeus vannamei

Abstract

The relevance of studying the biopotential of shrimp waste and their hydrolysates is due to the need for complex processing of secondary raw materials of aquatic organisms to obtain useful products. At the fish processing plant Vichyunai-Rus LLC when manufacturing food products from white-legged shrimp, up to 60 % of the mass of waste (cephalothorax, shell) remains. This raw material contains valuable organic components, but is not processed. The paper proposes its complex processing with the production of hydrolysates in two ways – high-temperature and enzymatic. During thermohydrolysis in the aquatic environment, three fractions are formed from shrimp waste (fatty, water-soluble and water-insoluble). After separation, the water-soluble fraction was sublimated, and the water-insoluble fraction was dried by convection. The fat fraction was further purified by washing in warm water. The general chemical composition of shrimp waste and hydrolysis products has been studied. It has been shown that water-soluble hydrolysates are a good source of protein components (66.6–71.6 %). In comparative studies of the amino acid composition of water-soluble hydrolysates, the presence of all essential amino acids is established with minor differences between the samples. Both hydrolysates are dominated by alanine, arginine, glycine, isoleucine, lysine, aspartic acid, tyrosine, valine (3.3–6.4 g/100 g of protein). In terms of formol-titratable nitrogen in fermentolisates, alkalase ferments shrimp waste more actively than collagenase. The fatty acid composition of lipids isolated by thermohydrolysis from shrimp waste has been analyzed. Shrimp oil is characterized by a high content of polyunsaturated fatty acids (44.7 %) with a relatively low content of omega-3 family acids (10.7 %) and a high content of omega-6 (33.9 %) at a ratio of 1 : 3.2 (close to the physiologically recommended). The organoleptic characteristics of water-soluble and water-insoluble shrimp hydrolysates have been studied. Due to the content of valuable biologically active components in hydrolyzates, their use as food and feed additives – sources of active peptides, high-molecular proteins, minerals and chitinous components – is recommended.