Summary
The use of protein hydrolysates, derived from animal and vegetable sources, in specific formulations, is an area of growing interest. The goal of this study was to develop different freeze-dried powder hydrolysates with high protein value, obtained from the enzymatic hydrolysis of manually deboned chicken carcasses (MDC), a by-product of the poultry industry which is normally used in the production of mechanically deboned meat (MDM). The raw material used was frozen manually deboned chicken carcasses (MDC), obtained from animals slaughtered at approximately 42 days of age with an average weight of 2.5 kg, acquired from an abattoir in southern Brazil. Before use, they were thawed under refrigeration, and cut into smaller pieces with a stainless steel knife for easier mixing during the hydrolysis time. Three commercial enzymes, Papain®, Flavourzyme® and Protamex® were used. Hydrolysis occurred in a thermostatic bath with controlled temperature, time and pH. The proximal compositions of the raw material and freeze-dried hydrolysates and the water activity of the freeze-dried hydrolysates were determined, and the following analyses carried out to control the hydrolysis: degree of hydrolysis, protein, total solids and ash contents, characterization of the amino acids in the hydrolysates, yield, percent hydrolysis and colour of the hydrolysates. The results were evaluated by the analysis of variance and Tukey’s means comparison test. The degree of hydrolysis was highest with Papain, followed by Protamex and Flavourzyme and after 120 minutes of hydrolysis the protein content did not vary significantly (p>0.05) between Papain and Flavourzyme. The amino acid composition showed that the hydrolysate obtained with papain had a composition closer to that recommended by the control authorities. It was concluded that the protein hydrolysates obtained from manually deboned chicken carcasses (MDC) had a high protein content, characterizing them as a promising raw material for the formulation of special diets.
Key words:
Manually deboned chicken carcass (MDC); Protein hydrolysate; Enzymatic hydrolysis