Abstract The ultrasound effect on functional and structural properties of hydrolysates of different bovine collagens (fibers, gelatines and hydrolysates) was evaluated. The enzymatically hydrolyzed samples (enzyme Alcalase®) with previous or simultaneous ultrasound treatment presented higher number of bands with shorter wavelengths (mid-FTIR). The ultrasound provided the samples with a higher hydrolysis degree and favored the antimicrobial activity, evidencing the advantages of its use in the process. Results revealed that higher hydrolysis degree does not always result in higher antioxidant activity. The use of ultrasound in the hydrolysis of these samples was seen to be effective, providing them with higher functionality and structural disruption.

Abstract Obtaining collagen and hydrolysates from mechanically separated chicken meat residue is an excellent way to add value to this waste. The aims of this study were to obtain collagen hydrolysates from chicken MSM residue using Alcalase® and Flavourzyme® enzymes, as well characterizing the functional, structural and thermal stability properties. The highest degree of hydrolysis was obtained using Alcalase®, 36.11%, while using Flavourzyme® resulted in 12.02%. The DSC analysis of the collagen indicated a denaturation temperature of 46.47 °C. The FTIR spectra of the crude collagen showed absorption peaks that were characteristic of amide bands A, B, I, II and III. In the spectra of the hydrolysed the area of the amide bands was reduced, and some peaks appeared between 800 and 1,200 cm-1. The disappearance of high molecular weight bands in the SDS-PAGE analysis also confirmed the hydrolysis of collagen. After the hydrolysis, the collagen presented reduced viscosity, the capacity to form foam, and foam stability. The emulsifying activity index was high in the hydrolysates in relation to the crude collagen. Thus, the use of Alcalase® and Flavourzyme® to obtain hydrolysates from collagen derived from chicken MSM residue was shown to be viable, and potentially useful for industrial applications.

Abstract This study aimed at evaluating the functional (antioxidant and antimicrobial activity) and structural properties of different bovine collagen hydrolysates obtained through ultrasound assisted enzymatic hydrolysis (Flavourzyme®). The use of previous or simultaneous ultrasound strengthened the enzymatic hydrolysis of bovine collagen samples, generating higher number of bands in wave number (cm-1). The best treatment was the enzymatic hydrolysis, while for the powder fiber and hydrolysate, it was the ultrasound hydrolysis. The sample that showed the highest inhibiting action to the gram-negative bacteria Salmonella choleraesuis growth and gram-positive bacteria Staphylococcus aureus hydrolyzed with enzyme and simultaneous ultrasound. Therefore, the enzymatic hydrolysis (Flavourzyme®) was concluded to enable the hydrolysis of samples, providing structural rupture and better functionality to the different bovine collagen hydrolysates.

RESUMO: Foram avaliados os efeitos da hidrólise enzimática (pepsina) assistida com ou sem ultrassom nas propriedades funcionais de hidrolisados de diferentes colágenos. Foi analisado o grau de hidrólise, a atividade antioxidante (DPPH) e a atividade antimicrobiana (MIC). O tratamento que possibilitou maior atividade antioxidante para a amostra fibra foi com a utilização de 4% de enzima e ultrassom concomitante (40,7%), levando a um grau de hidrólise de 21,7%. Para a amostra fibra pó o tratamento de hidrólise com uso de 4% de enzima resultou em menor teor de proteína (6,97mg/mL), maior grau de hidrólise (19,9%) e maior atividade antioxidante (38,6%). Os hidrolisados mostraram capacidade inibitória contra a bactéria gram-negativa Salmonella choleraesuis e gram-positiva Staphylococcus aureus. Pode-se concluir que a hidrólise enzimática concomitante, ou não, ao uso do ultrassom apresentou aumento da funcionalidade das amostras fibra e fibra pó. Para as demais amostras, sua utilização como tratamento complementar, a hidrólise não foi interessante, devido aos piores resultados de atividade antioxidante (DPPH) encontrados. Porém, proporcionou maior grau de hidrólise.

ABSTRACT: Enzymatic hydrolysis (pepsin) assisted with or without ultrasound in the functional properties of hydrolyzates from different collagens were analyzed. Degree of hydrolysis, antioxidant activity (DPPH) and antimicrobial activity (MIC) were assessed. The treatment that resulted in greater antioxidant activity for the fiber sample was with the use of 4% of enzyme and concomitant ultrasound (40.7%), leading to a degree of hydrolysis of 21.7%. For the powdered fiber sample the hydrolysis treatment with use of 4% of enzyme resulted in lower protein content (6.97mg/mL), higher degree of hydrolysis (19.9%) and greater antioxidant activity (38.6%). The hydrolyzates showed inhibitory capacity against gram-negative bacteria Salmonella choleraesuis and gram-positive bacteria Staphylococcus aureus. It can be concluded that enzymatic hydrolysis concomitant or not with the use of ultrasound increased the functionality of the fiber and powdered fiber samples, for the other samples its use as supplementary treatment was not productive, due to the worse results of antioxidant activity (DPPH) reported. However, it provided greater hydrolysis degree.