The relationship between protein structure and aggregation, as well as heat-induced gelling properties, of seven dried egg white (DEW) products was investigated. Strong correlations were found between average molecular weight and hydrophobicity plus surface SH groups of DEW-soluble protein aggregate (SPA). This suggests that hydrophobic interactions and disulfide bond formation between protein molecules were involved in the aggregation. The average molecular weight of DEW products with alkaline pHs was relatively higher than those with neutral pHs and the same degree of protein unfolding, probably because of more disulfide bond formation between protein molecules. In addition, strong correlations were found between hydrophobicity, surface SH groups plus average molecular weight of DEW-SPA, and physical properties of the gels from DEW products. These data indicated that controlling the aggregation of DEW proteins in the dry state is crucial to controlling the gelling properties of DEW.

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We studied the effect of egg white hydrolysate (EWH) on swimming endurance in mice. 7‐week‐old male ddY mice (28–30 g) were divided into three groups and fed an AIN‐93G diet supplemented with casein (n = 8), EWH (n = 7), or egg white protein (EWP, n = 8) for 14 days. From day 11, the mice underwent a swimming test daily with a weight load equivalent to 10% of their body weight, and the lengths of time they swam were recorded. Blood was sampled for testing on the last day of the study. We observed that increases in the swimming duration through day 14 were significantly greater in the EWH group than in the casein group (p = 0.049). As a factor underlying this, the hexanoyl‐lysine level in blood was confirmed to be decreased in the former group (p = 0.013). These findings indicate that consumption of EWH extended the swimming duration and suggest the mechanistic involvement of an antifatigue effect mediated by its antioxidant activity.

The properties of ostrich egg were examined by measuring proportional parts, shape index, yolk index, percentage of thick albumen, pH of albumen and yolk, chemical compositions, color, rheological properties of albumen, compared with those of white leghorn hen egg. The shell of ostrich egg was extremely thick, the ratio of shell weight to egg weight was 20.0% (12.4%: hen egg), and yolk index was 0.17 (0.39: hen egg). Chemical properties of ostrich egg were similar to those of hen egg. The adhesion in physical properties of ostrich egg albumen was higher than that of hen egg. SDS-PAGE patterns of albumen and yolk were different between ostrich egg and hen egg. As the weight of ostrich egg is about 20 times as much as that of hen egg, ostrich egg is expected as an useful food resource.