SUBSTANTIATION OF RATIONAL PARAMETERS FOR COMPLEX PROCESSING OF SECONDARY RAW MATERIALS OF SPRAT PRODUCTION USING THE METHOD OF HIGH-TEMPERATURE HYDROLYSIS

Abstract

Processing of secondary raw materials from production of canned food «Sprats in oil» is considered. Comprehensive technology is developed for producing of protein, fat, and protein-mineral food additives from the sprat waste, as smoked sprat heads, using the method of high temperature hydrolysis. Rational method of the hydrolysis is substantiated, including preliminary separation of fat in fatty raw materials and its enzymatic-thermal treatment. The optimal values of temperature and duration of hydrolysis in autoclave are determined. Balances of organic substances are calculated for the main operations. This new technology was tested for fatty (24 %) and medium fat (13 %) raw materials under the temperature of 130–160 о С. The hydrolyzed organic mass was divided into fat, protein, and mineralized fractions and proteinfat emulsion. Food additives containing low molecular weight water-soluble peptides and high molecular weight insoluble proteins were extracted from the protein fraction by freeze-drying and mineral compounds were extracted from the mineral fraction by convective drying. The proteins were extracted more thoroughly, so the content of low molecular weight peptides in the freeze-dried hydrolysate of protein fraction was > 80 %. The produced additives have pleasant organoleptic properties and are sanitary safe. They are tested with some seafood, with positive result. The developed technology for processing of smoked waste is economically valuable and allows to solve the problem of pollution in the fish smoking industry.

Keywords

• sprat
• smoked sprat heads
• thermohydrolysis
• enzymatic-thermal hydrolysis
• protein food additive
• mineralized fraction
• protein-fat emulsion