College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; National Engineering Research Center for Fruits and Vegetables Processing, Beijing 100083, China.
College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China; National Engineering Research Center for Fruits and Vegetables Processing, Beijing 100083, China.
Int J Biol Macromol. 2021 Dec 1;192:444-451. doi: 10.1016/j.ijbiomac.2021.09.187. Epub 2021 Oct 1.
Pumpkin starch (PS) was extracted from Cucurbita maxima and utilized to prepare films in combination with cellulose nanocrystal (CNC) and cellulose nanofiber (CNF), using a solvent casting strategy. The PS was characterized to contain 26.6% of amylose, exhibiting a "B"-type crystalline structure and high stability against thermal degradation. PS/CNF films showed better thermal stability than PS/CNC films, whereas the CNC was more effective than CNF for enhancing the tensile strength (TS) of the films. The nanocomposite films containing 1% CNC showed the highest TS of 30.32 MPa. Fourier transform infrared spectra revealed stronger hydrogen bonding in the PS/CNC films, likely contributing to the observed high mechanical strength. CNC and CNF both decreased the transparency of PS films, by 5.2% and 13.1%, respectively. Overall, the properties of PS composite films can be effectively modified by incorporating CNC and CNF, as PS/CNC films with high mechanical strength and PS/CNF films with good thermal stability. Our results indicate that PS is a suitable material for CNC/CNF composite film fabrication. These films are expected to be especially useful in food packaging applications.
南瓜淀粉（PS）从南瓜中提取，并用溶剂浇铸法与纳米纤维素晶体（CNC）和纳米纤维素纤维（CNF）结合制备薄膜。对 PS 进行了表征，结果表明它含有 26.6%的直链淀粉，呈现“B”型结晶结构，热稳定性高，不易降解。PS/CNF 薄膜的热稳定性优于 PS/CNC 薄膜，而 CNC 比 CNF 更能有效提高薄膜的拉伸强度（TS）。含 1% CNC 的纳米复合材料薄膜具有最高的 TS 为 30.32 MPa。傅里叶变换红外光谱表明 PS/CNC 薄膜中存在更强的氢键，这可能是观察到高强度的原因。CNC 和 CNF 分别使 PS 薄膜的透明度降低了 5.2%和 13.1%。总的来说，通过掺入 CNC 和 CNF，可以有效改善 PS 复合薄膜的性能，使 PS/CNC 薄膜具有较高的机械强度，PS/CNF 薄膜具有良好的热稳定性。我们的研究结果表明，PS 是一种适合制备 CNC/CNF 复合膜的材料。这些薄膜有望在食品包装应用中特别有用。
