羧甲基壳聚糖/氧化羧甲基纤维素/姜黄素复合膜的制备及其在草莓涂膜保鲜中的应用

Fabrication of a Carboxymethyl Chitosan/Oxidized Carboxymethylcellulose/Curcumin Composite Film and Its Application in the Film-Coating Preservation of Strawberry

摘要:

采用铸膜法制备了一种羧甲基壳聚糖/氧化羧甲基纤维素/姜黄素（CMCHS/ OCMC/ CR）三元复合材料。红外光谱和扫描电子显微镜分析显示，复合膜断面结构均匀，无分层，但表面粗糙度有所增大。与不添加姜黄素相比，复合材料具有更好的断裂应力（20.10 MPa），断裂伸长率（18.97%），抗真菌性能（黑曲霉抑菌圈15.33 mm，青霉抑菌圈14.58 mm）和透水性（2.11×10-3 g·m-1·kPa-1·h-1）。草莓保鲜实验结果表明，CMCHS/OCMC/CR复合材料涂膜可减缓贮藏过程中的失重率和可滴定酸、可溶性固形物、还原糖含量的下降。经贮藏8 d，草莓失重率比较空白对照减少了11.38%，较阳性对照减少了1.27%，硬度，可滴定酸、可溶性固形物、还原糖含量的下降分别较空白对照减少了10.00%、42.72%、7.39%、9.32%，较阳性对照分别减少了5.54%、7.42%、2.39%、11.12%。因此CMCHS/OCMC/CR（1%, m/m）复合膜显示出良好护色和抑制霉菌生长的保鲜作用，可作为良好的涂膜抗菌材料应用于食品包装材料中。

Abstract:

A water-soluble chitosan hydrogel, carboxymethyl chitosan/oxidized carboxymethylcellulose/curcumin (CMCHS/OCMC/CR) ternary composite, was prepared by the casting method. FTIR and SEM showed that the cross-section structure of the composite film was uniform without stratification, but the surface roughness was higher than that of the CMCHS/OCMC film. Compared to the film with no curcumin, CMCHS/OCMC/CR showed better fracture stress (20.10 MPa), elongation at break (18.97%), anti-fungal properties (Aspergillus niger inhibition zone 15.33 mm, Penicillium inhibition zone 14.58 mm), and water vapor permeability (2.11×10-3 g·m-1·kPa-1·h-1). The film-coating experiments indicated that coating with CMCHS/OCMC/CR composite could effectively decelerate the weight loss as well as the decrease in titratable acid, soluble solids, and reducing sugar contents in strawberry during storage. After storage for eight days, the weight loss rate of strawberry in the CMCHS/OCMC/CR group decreased by 11.38% and 1.27% compared to those in the blank and positive control groups. Moreover, the hardness, titratable acid, soluble solids, and reducing sugar of strawberry in the CMCHS/OCMC/CR group decreased by 10.00%, 42.72%, 7.39%, and 9.32% compared to the blank control and by 5.54%, 7.42%, 2.39% and 11.12% compared to the positive control, respectively. Therefore, the CMCHS/OCMC/CR (1%, m/m) composite film showed good preservative effects of color preservation and inhibition of mold growth and could be used as an effective antibacterial coating material in food packaging materials.