2种复合涂膜对哈密瓜的采后保鲜效果

Effect of two compound coatings on storage quality of cantaloupe

【目的】研究羧甲基壳聚糖与海藻酸钠复合涂膜对哈密瓜的保鲜效果,为哈密瓜的采后保鲜提供参考。【方法】将羧甲基壳聚糖、海藻酸钠与肉桂醛复配,制备成2种复合涂膜保鲜剂,对哈密瓜进行涂膜保鲜,以蒸馏水处理为对照,于(19±2)℃下贮藏。通过测定3组哈密瓜在贮藏期间的失重率、硬度、抗坏血酸(Vc)含量、过氧化物酶(POD)活性、感官评分以及霉菌和酵母菌数量,分析2种复合涂膜对哈密瓜的保鲜效果。【结果】常温贮藏35d时,海藻酸钠组和羧甲基壳聚糖组哈密瓜的失重率分别为7.26%和10.42%,硬度分别为2.82和2.52kg/cm2,Vc含量分别为11.82和14.80 mg/hg,POD活性分别为2.61和3.44 U,霉菌、酵母菌总数量分别为3.92和3.83log CFU/g,感官评分分别为5.13和5.74,均显著优于对照组(P<0.05)。【结论】2种复合涂膜都能降低哈密瓜的失重率,维持较高的硬度和Vc含量,提高POD活性,保持哈密瓜良好的感官品质,抑制果肉中霉菌和酵母菌的繁殖,且以羧甲基壳聚糖复合涂膜的保鲜效果更佳。

[Objective] This study investigated the effects of talginate compound coating and carboxym- ethyl chitosan compound coating on preservation of cantaloupe. [Method] Cantaloupes were coated with two antistaling agents based on carboxymethyl chitosan with cinnamaldehyde and sodium alginate with cin- namaldehyde. Distilled water was used as CK and all 3 groups were stored at （19±2） ℃. The effects of the two compound preservative coatings were analyzed by measuring and comparing the weight loss rate, firm- ness,ascorbic acid （Vc） content,peroxidase （POD） activity, sensory indicator and mold and yeast count. [Result] After 35 d storage at room temperature,the weight loss rates of sodium alginate group and car- boxymethyl chitosan group were 7.26% and 10.42G ,their firmness values were 2.82 and 2.52 kg/cm2 , their Vc contents were 11.82 and 14.80 mg/hg,their POD activities were 2. 61 and 3.44 U,their mould and yeast counts were 3.92 and 3.83 log CFU/g,and their sensory evaluation scores were 5.13 and 5.74, respectively. All indexes were significantly better than the control group（P〈0.05）. [Conclusion] Both compound coatings could reduce weight loss, maintain high firmness and Vc content, improve POD activity, keep good sensory evaluation, and inhibit pulp mold and yeast propagation. In addition, carboxymethylcellu- lose chitosan coating was better.