壳聚糖涂膜对鸡蛋品质的影响

Effect of Chitosan-coating on Egg Quality

通过对新鲜鸡蛋涂擦不同质量浓度的壳聚糖溶液,旨在研究壳聚糖对鸡蛋品质的影响。试验将300枚新鲜鸡蛋随机分成6组,分别涂上0、0.5、1.0、1.5、2.0g/100mL和2.5g/100mL壳聚糖溶液,25℃条件下贮存5周。每周从每个处理中取10枚鸡蛋测定鸡蛋失重率、哈夫单位、蛋黄指数和蛋清pH值。结果表明,第5周与第1周相比,不涂壳聚糖的鸡蛋失重率和蛋清pH值显著升高(P<0.05)、哈夫单位和蛋黄指数显著降低(P<0.05)。5周时,与不涂壳聚糖的鸡蛋相比,所有涂壳聚糖的鸡蛋失重率显著降低(P<0.05),蛋黄指数显著升高(P<0.05);涂1.0、1.5、2.0g/100mL和2.5g/100mL壳聚糖的鸡蛋哈夫单位显著升高(P<0.05),蛋清pH值显著降低(P<0.05);涂1.5、2.0g/100mL和2.5g/100mL壳聚糖的鸡蛋间比较,蛋质量损失率、哈夫单位、蛋黄指数和蛋清pH值差异均不显著(P>0.05)。用0.5g/100mL壳聚糖涂擦的鸡蛋5周时降到C级,相当于不涂壳聚糖的鸡蛋3周时的级别;用1.0、1.5、2.0g/100mL和2.5g/100mL壳聚糖处理的鸡蛋5周时降到B级,相当于不用壳聚糖处理的鸡蛋2周时的级别。该实验证明壳聚糖能够延长鸡蛋货架期。

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.