Fatores que afetam a produção de moléculas de sabor de hidrolisados de vísceras caprinas

Abstract

The goat viscera has been studied for its potential to produce protein hydrolysates, considering its protein concentration and amino acid composition. Thus, the aim was to investigate the aromatic quality of hydrolysates obtained from goat viscera. In a first study, it was sought 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 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 higher 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. The application of the two heat treatments resulted in the production of goat by-product protein hydrolysates with different volatile profiles. In a second study, the action of three proteolytic enzymes in the production of protein hydrolysates from goat viscera was investigated, and their use in the production of flavoring products. The production of flavor/aroma precursor molecules and the formation of volatile compounds resulting from the application of different proteases were investigated; three single hydrolysis treatments (HA - Alcalase®, HF - Flavourzyme®, HN - Neutrase®) and a combined treatment (HFN - Flavourzyme® and Neutrase®). The highest degree of hydrolysis was obtained with Alcalase (26.74%), as well as the highest number and highest concentration of volatile compounds (23 volatiles and 27.5 µg/100mL, respectively). The main volatiles identified in the hydrolysates included acids, aldehydes, pyrazines, terpenes and Streacker aldehydes. Water-soluble and fatsoluble aroma precursors were investigated, with higher concentrations in HF and HFN hydrolysates, probably due to the low participation of these precursors in the formation of volatile compounds. Therefore, the use of Alcalase in the proteolysis of goat viscera stood out compared to other enzymes, providing impactful aroma compounds for the meat flavor. In addition, a review article on potential strategies for the use and application of goat and sheep by-products was produced. The review also presented remarkable evidence regarding the nutritional, technological, functional, bioactive and flavoring potential aspects of goat and sheep by-products, as a significant potential to provide new and valuable food ingredients.