PREPARATION AND CHARACTERIZATION OF CHICKEN EGG WHITE HYDROLYSATE
Blaž Cigić and Marija Zelenik-Blatnik
Department of Food Science and Technology,
Biotechnical Faculty, Jamova 101, 1000
freshly laid chicken eggs was thermally treated at various pH values in order
to find optimal conditions for subsequent enzymatic hydrolysis with Alcalase (Subtilisin Carlsberg).
Alkalisation to pH 10 followed by 30 minutes heating between 75 °C and 80 °C resulted in irreversible denaturation of Alcalase
inhibitors and formation of soluble aggregates of denatured proteins. Denatured albumen was most effectively
60 °C and pH 8.5. Hydrolysis rate between pH 7 and pH 9 was relatively high and therefore hydrolysis without pH regulation was performed. Bitter peptides, which were formed as a result of Alcalase hydrolysis, were degraded with Flavourzyme, a mixture of fungal exopeptidases and endopeptidases. Degree of hydrolysis over 30 and high yield of peptides soluble over a wide pH range were obtained by combination of peptidases. Hydrolysate, which contained substantial amount of dipeptides and tripeptides was only moderately bitter and had an overall acceptable flavour.
Key words: egg white, hydrolysate, hydrolysis, Flavourzyme, Alcalase, peptides, inhibitor