College of Food Science and Engineering, Northwest A&F University, No. 22 Xinong Road, Yangling, Shaanxi 712100, China.
State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Lihu Road 1800, Wuxi, Jiangsu 214122, China.
Int J Biol Macromol. 2018 Oct 15;118(Pt A):722-730. doi: 10.1016/j.ijbiomac.2018.06.089. Epub 2018 Jun 23.
Nano-bacterial cellulose (BC), as a reinforcing agent, was used to prepare the agar-based edible films. Effects of BC content (0, 3, 5, 8 and 10%, wt% based on the agar) on the rheological properties of film-forming solution (FFS), and on structure, morphology, crystallinity, and thermal properties of films were investigated. Results of rheological and FTIR analyses revealed that interactions between BC and agar were formed through hydrogen bonds. The crystallinity and the thermal stability of films were improved by addition of BC analyzed by XRD and TGA, respectively. Compared with high BC concentrations (8-10%), a good dispersion of BC at low concentrations (3-5%) in the films was observed by SEM. Moreover, BC addition (10%) significantly decreased moisture content (MC), water solubility (WS) and water vapor permeability (WVP) by 60.4%, 13.3% and 25.7%, respectively. The tensile strength (TS) of films increased from 22.10 to 44.51 MPa after addition of BC (0-10%), whereas the elongation at break (EAB) initially increased with increasing BC concentrations (0-5%), and then decreased with further addition of BC (8-10%). Consequently, agar-based edible films reinforced by moderate nano-BC have the potential as a packaging film for food products.
纳米细菌纤维素（BC）作为增强剂，用于制备琼脂基可食用膜。研究了 BC 含量（0、3、5、8 和 10%，基于琼脂的重量%）对成膜溶液（FFS）的流变性能，以及对膜的结构、形态、结晶度和热性能的影响。流变学和傅里叶变换红外光谱（FTIR）分析的结果表明，BC 和琼脂之间通过氢键形成相互作用。通过 X 射线衍射（XRD）和热重分析（TGA）分别分析，发现添加 BC 提高了膜的结晶度和热稳定性。与高 BC 浓度（8-10%）相比，SEM 观察到低 BC 浓度（3-5%）在膜中具有良好的分散性。此外，添加 BC（10%）使水分含量（MC）、水分溶解度（WS）和水蒸气透过率（WVP）分别降低了 60.4%、13.3%和 25.7%。添加 BC（0-10%）后，膜的拉伸强度（TS）从 22.10 MPa 增加到 44.51 MPa，而断裂伸长率（EAB）最初随着 BC 浓度（0-5%）的增加而增加，然后随着进一步添加 BC（8-10%）而降低。因此，适度纳米 BC 增强的琼脂基可食用膜有望成为食品包装膜。
