Effects of thermal processing on the flavor molecules of goat by-product hydrolysates

Abstract

The aim of this study was to obtain flavor molecules from goat by-product hydrolysates, emphasizing the thermal action during processing. A mixture of by-products submitted or not to the inactivation of endogenous enzymes was used, followed by hydrolysis with the proteolytic enzyme Alcalase® (Bacillus licheniformis), and autoclaving after hydrolysis. The production of hydrolysates provided both quantitative and qualitative data on the precursors involved in the aromatic formation of protein hydrolysates. The inactivation process of endogenous enzymes resulted in hydrolysates with a higher degree of hydrolysis and greater protein content. The autoclaving process produced a significant increase in the concentration of free amino acids and maltose and a reduction in the glucose content. Application of the two heat treatments resulted in the production of goat by-product protein hydrolysates with different volatile profiles. The goat by-product protein hydrolysate without heat treatment but with autoclaving (HCA), showing a higher concentration of flavor precursors and the formation of heterocyclic volatiles, is expected to impact the aroma quality of goat hydrolysates.

Keywords: Autoclaving; Flavor; Goat by-products; Inactivation; Protein hydrolysates; Volatile compounds.