Department of Food Science and Technology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China.
Department of Food Science and Technology, 100 Wiegand Hall, Oregon State University, Corvallis, OR 97331, USA.
Int J Biol Macromol. 2019 Oct 15;139:1232-1238. doi: 10.1016/j.ijbiomac.2019.08.113. Epub 2019 Aug 13.
This study used electrostatic spraying (ES) system as an efficient technique for strawberry preservation with chitosan (CH) coating. The effects of CH deacetylation degree (DD, 81.0, 88.1 and 95.2%) on the qualities (weight loss, pH, total soluble solids (TSS), firmness, flavonoids content, malondialdehyde (MDA) content and superoxide dismutase (SOD) activity and mold growth) of strawberry during cold storage were investigated. Results showed that CH coating by ES formed more continuous and uniform protective layer compared with conventional spraying (CS). CH coating effectively enhanced the overall quality and extended shelf life of strawberry at least 2 days. CH coating with 81.0% and 88.1% DD were more effective in reducing weight loss of strawberry, and CH coating with 88.1% DD could better maintain TSS content, while CH coating with 95.2% DD delayed the decline in flavonoids more obviously. However, DD had no significant impact on pH, firmness, SOD activity, MDA and mold growth of coated samples. The evaluation criteria indicated CH coating with 88.1% DD had better preservation performance with the highest synthetic value (6.17) during storage. These findings suggest that CH coating especially with 88.1% DD by ES, as a safe, cheap and efficient technique, has great potential for industrial application of fruit preservation.
本研究采用静电喷雾（ES）系统作为一种有效的草莓保鲜技术，并用壳聚糖（CH）进行涂层处理。考察了 CH 脱乙酰度（DD，81.0、88.1 和 95.2%）对冷藏过程中草莓品质（失重率、pH 值、总可溶性固形物（TSS）、硬度、类黄酮含量、丙二醛（MDA）含量、超氧化物歧化酶（SOD）活性和霉菌生长）的影响。结果表明，与传统喷雾（CS）相比，ES 形成的 CH 涂层更连续、均匀。CH 涂层能有效提高草莓的整体品质，延长货架期至少 2 天。DD 为 81.0%和 88.1%的 CH 涂层能更有效地减少草莓的失重率，DD 为 88.1%的 CH 涂层能更好地保持 TSS 含量，而 DD 为 95.2%的 CH 涂层能更明显地延缓类黄酮的下降。然而，DD 对涂层样品的 pH 值、硬度、SOD 活性、MDA 和霉菌生长没有显著影响。评价标准表明，在贮藏过程中，DD 为 88.1%的 CH 涂层具有更好的保鲜性能，综合值（6.17）最高。这些发现表明，CH 涂层，特别是 DD 为 88.1%的 ES 涂层，作为一种安全、廉价、高效的技术，在水果保鲜的工业应用中具有很大的潜力。
