Effect of Chitosan-coating on Egg Quality

A total of 300 fresh eggs were randomly allocated into 6 treatment groups, and coated with 0, 0.5, 1.0, 1.5, 2.0 g/100 mL and 2.5 g/100 mL of chitosan. Then the eggs were stored at 25 ℃ for 5 weeks. Ten eggs were chosen from every treatment per week for determination of the weight loss ratio, Haugh unit, yolk index and albumen pH. The result showed that after 5 weeks storage, the weight loss ratio and albumen pH were significantly increased (P0.05), meanwhile, the Haugh unit and yolk index of the eggs significantly decreased (P0.05) in non-chitosan coated egg group. At 5 wk, compared with the eggs nocoated with chitosan, the weight loss ratio of all the eggs coated with chitosan was significantly decreased (P0.05) and yolk index was significantly increased (P0.05). The Haugh unit of the eggs coated with 1.0, 1.5, 2.0 g/100 mL and 2.5 g/100 mL chitosan was significantly increased (P0.05) and albumen pH was significantly decreased (P0.05). It had no significant difference on the weight loss ratio, Haugh unit, yolk index and albumen pH among the eggs coated with 1.5, 2.0 and 2.5% of chitosan(P0.05). The grade of the eggs coated with 0.5 g/100 mL chitosan at 5 wk was C , which was equal to the grade of the eggs nocoated at 3 wk. The grade of the eggs coated with 1.0, 1.5, 2.0 g/100 mL and 2.5 g/100 mL chitosan at 5 wk was B , which was equal to the grade of the eggs nocoated at 2 wk. The shelf life of eggs were prolonged significantly by coating of chitosan.