Department of Food Science and Technology, Faculty of Agriculture, Urmia University, P.O. Box 57561-51818, Urmia, Iran.
Int J Biol Macromol. 2020 Nov 15;163:666-675. doi: 10.1016/j.ijbiomac.2020.07.041. Epub 2020 Jul 8.
In this study, biodegradable film based on pectin modified with Nanoclay and methylene blue was prepared. The Physicomechanical properties of the prepared film, including: thickness, water solubility, water vapor permeability (WVP), antioxidant activity and color properties were investigated. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Differential scanning calorimetry (DSC) and texture analysis techniques were used to investigate the physical and mechanical properties of the films. The optimum Pec/Clay/MB film was used as a colorimeter sensor to detect and measure vitamin C. The results showed that the addition of Nanoclay to the film increased the thickness and decreased the solubility of water and reduced the WVP. The addition of methylene blue had no significant effect on the thickness, but increased water solubility and increased antioxidant activity. The addition of Nanoclay increased the tensile strength (TS) of the film, but decreased its elongation at break (EB). The addition of Nanoclay increased the melting temperature of the film and decreased its crystallization temperature. In the SEM images, the clay particles at 50-100 nm in the film structure were characterized. Nanoclay and methylene blue reduced the surface cleavage of the film. Pec/Clay/MB film color was changed from blue to colorless in the presence of vitamin C. The linear range of vitamin C measurement was 10 to 500 and the detection limit was 10. By detecting the color changes of the film in the presence of vitamin C, the amount of this vitamin was measured in orange, kiwi and tangerine juice. The accuracy of the data was evaluated by the titration method. The sensor accuracy was obtained over 90%.
在这项研究中，制备了一种基于果胶的可生物降解膜，并用纳米粘土和亚甲蓝进行了修饰。研究了所制备薄膜的物理机械性能，包括：厚度、水溶性、水蒸气透过率（WVP）、抗氧化活性和颜色特性。扫描电子显微镜（SEM）、傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、差示扫描量热法（DSC）和质地分析技术用于研究薄膜的物理和机械性能。将最佳的 Pec/Clay/MB 薄膜用作比色传感器，以检测和测量维生素 C。结果表明，向薄膜中添加纳米粘土会增加厚度，降低水的溶解度，并降低 WVP。添加亚甲蓝对厚度没有显著影响，但会增加水的溶解度并提高抗氧化活性。添加纳米粘土会增加薄膜的拉伸强度（TS），但会降低其断裂伸长率（EB）。添加纳米粘土会增加薄膜的熔融温度，并降低其结晶温度。在 SEM 图像中，薄膜结构中 50-100nm 的粘土颗粒特征明显。纳米粘土和亚甲蓝减少了薄膜表面的开裂。 Pec/Clay/MB 薄膜在存在维生素 C 的情况下颜色从蓝色变为无色。维生素 C 测量的线性范围为 10 至 500，检测限为 10。通过检测存在维生素 C 时薄膜的颜色变化，测量了橙汁、猕猴桃和橘子汁中这种维生素的含量。通过滴定法评估数据的准确性。传感器的准确率超过 90%。
