Quality, protease inhibitor and gelling property of duck egg albumen as affected by storage conditions

Physicochemical properties, trypsin inhibitory activity, and gelling properties of albumen from duck egg during 15 days of storage at 4 A degrees C and room temperature (28-30 A degrees C) were studied. As the storage time increased, Haugh unit and moisture content decreased, while the pH value increased (P < 0.05). The rate of changes was lower at 4 A degrees C. Trypsin inhibitory activity in albumen from egg stored at 4 A degrees C was higher than that kept at room temperature throughout the storage time (P < 0.05). Nevertheless, no differences in protein patterns were observed during the storage. Based on texture profile analysis, the highest hardness, gumminess, and chewiness were found at day 3 for room temperature and at day 6 for 4 A degrees C. Higher values were attained for eggs kept at 4 A degrees C. Conversely, albumen gels made from eggs stored at room temperature exhibited higher cohesiveness, adhesiveness, springiness, resilience than those kept at 4 A degrees C. The gels had the lowered whiteness when eggs were stored for a longer time, particularly at room temperature. Thus, storage condition directly affected the quality of albumen from duck egg.