The aim of this work was to preparation of edible films based on whey protein isolate/pectin (WPIP) that containing betanin pigments (BP) and copper (I) oxide nanoparticles (CuO). To do so, effects three different levels of betanin pigments (BP) (%W/V = 0, 2.5 and 5) and copper (I) oxide nanoparticles (CuO) (%W/V = 0, 2, 4) were evaluated via a central composite design to scrutinize the physical–chemical characteristics of the produced nanocomposite film. The results showed that betanin pigments and copper (I) oxide nanoparticles increased the antioxidant capacity and decreased the water vapor permeability of the samples (P < 0.05). Also, an increase in redness (a*) index and decrease in lightness (L*) and yellowness (b*) indices were observed following the addition of betanin pigments. Addition of the nanoparticles displayed no effect on (a*) index but decreased the (b*) index. It was found that combined application of pigments and nanoparticles increased the tensile strength and elongation at the breaking point, which was statistically significant (P < 0.05). In general, the addition of BP and CuO increased the thickness, moisture and antioxidant capacity of the samples and decreased the solubility, WVP (P < 0.05). Results of Fourier-transform infrared spectroscopy (FT-IR) analysis suggested an electrostatic interaction between WPIP, the nanoparticle and the pigment. The X-ray differentiation images showed that films containing the nanoparticles and pigments reduced the crystalline structure of the WPIP. Differential scanning calorimeter outputs of the film samples containing the nanoparticles and betanin displayed stronger thermal stability. Moreover, the field emission scanning electron microscopy results showed that the BN and CuO contributes to the cohesiveness of the surface particles and decreases the gap and crack sizes. Finally, the analysis of antimicrobial activity against E. coli and B. cereus showed that BP and CuO increases the diameter of zone of inhibition (halo) and the films displayed high antimicrobial activity. In general, it can be stated that inclusion of betanin pigment (BP) and NOC in the nanocomposite film formula results in physical–chemical and structural improvement of the nanocomposite film.

这项工作的目的是制备基于乳清蛋白分离物/果胶 (WPIP) 的可食用薄膜，其中含有甜菜碱色素 (BP) 和氧化铜 (I) 纳米颗粒 (CuO)。为此，评估了三种不同水平的甜菜碱色素 (BP) (%W/V = 0、2.5 和 5) 和氧化铜 (I) 纳米粒子 (CuO) (%W/V = 0、2、4) 的影响通过中央复合设计来检查所生产的纳米复合薄膜的物理化学特性。结果表明，甜菜素颜料和氧化铜（I）纳米颗粒提高了样品的抗氧化能力，降低了样品的水蒸气渗透性（P < 0.05）。此外，在添加甜菜碱颜料后，观察到红度 (a*) 指数增加，亮度 (L*) 和黄度 (b*) 指数降低。添加纳米粒子对 (a*) 指数没有影响，但会降低 (b*) 指数。结果发现，颜料和纳米粒子的联合应用增加了断裂点的拉伸强度和伸长率，具有统计学意义（P < 0.05）。总体而言，BP和CuO的添加增加了样品的厚度、水分和抗氧化能力，降低了溶解度WVP（P < 0.05）。傅里叶变换红外光谱 (FT-IR) 分析结果表明 WPIP、纳米颗粒和颜料之间存在静电相互作用。X 射线微分图像显示含有纳米颗粒和颜料的薄膜降低了 WPIP 的晶体结构。含有纳米颗粒和甜菜碱的薄膜样品的差示扫描量热仪输出显示出更强的热稳定性。此外，场发射扫描电子显微镜结果表明，BN 和 CuO 有助于表面颗粒的凝聚力，并减小间隙和裂纹尺寸。最后，对抗菌活性的分析E. coli和B. cereus表明 BP 和 CuO 增加了抑制区（晕圈）的直径，并且薄膜显示出高抗菌活性。一般来说，可以说在纳米复合膜配方中加入甜菜碱色素 (BP) 和 NOC 会导致纳米复合膜的物理化学和结构改进。