Abstract:

In this study, changes in chemical composition, gel characteristics and color of preserved chicken eggs were
monitored during pickling for up to several weeks in the presence of 0.3% divalent cation (ZnCl2). The results showed that
free alkalinity, hardness, elasticity, cohesiveness and chewiness increased significantly (P < 0.05), and gelation capacity
became lower (P < 0.05) during the first 28 days of pickling, all of which tended to be stable as pickling went on (P > 0.05).
Most protein (> 86.6 kD) was degraded in the first 14 days of pickling. As the alkalinity of preserved eggs increased, smallmolecule
peptides (14.3 and 10 kD) accumulated continuously, and the total free amino acid content significantly decreased
(P < 0.05). In contrast, protein degradation did not continue to occur as the pickling period was prolonged from 21 days to
28 days. L* and b* values of preserved eggs changed in a manner opposite to a* value. Changes in the color of egg white
and yolk were significantly negatively correlated to pickling time, free alkalinity and free amino acid content, respectively.
Furthermore, a negative correlation was also seen between changes in whiteness values of egg white and yolk.

Key words: preserved egg, protein degradation, gel property, chromatic aberration