Effect of enzymatic hydrolysis on the structural and protein solubility of eggshell membrane

Abstract

Eggshell membrane (ESM) is considered food waste or a by-product of the egg processing industry. It has huge application potential in the engineering, nutraceutical, pharmaceutical, and cosmeceutical sectors. Recently, researchers have shown an increased interest in ESM hydrolysate (ESMH) from enzymatic hydrolysis in biomaterial applications. Nonetheless, there is lacking of information on the characteristics of ESMH. Thus, this study aims to characterise ESMH attained from enzymatic hydrolysis. The ESM was manually separated from the eggshell, and then subjected to enzymatic hydrolysis using two (2) different enzymes (alcalase (Al) and trypsin (Tr)). The alcalase-treated ESMH (Al-ESMH) and trypsin-treated ESMH (Tr-ESMH) were then characterised by using Ultra-violet Visible Spectroscopy (UV-Vis) and Fourier Transform Infrared Spectroscopy (FTIR). UV spectra displayed two intense absorbance peaks; 238 nm and 280 nm. The second peak at 280 nm was used to quantify the soluble protein in ESMHs. The results showed that the Al-ESMH had higher protein solubility (17.25 +/- 0.11 mg/mL) than the Tr-ESMH (3.28 +/- 0.11 mg/mL) and ESM (2.11 +/- 0.19 mg/mL). The FTIR spectra of ESMHs prove the presence of peptides for both treated ESM samples after enzymatic hydrolysis.