Preparation and Characterization of Copper Oxide Nanoparticle‐Reinforced Bionanocomposite Films From Taro ( <scp> <i>Colocasia esculenta</i> </scp> (L.) Schott) Starch and <scp> <i>Aloe vera</i> </scp> ( <scp> <i>Aloe barbadensis</i> </scp> (L.) Burm

ABSTRACT The current study investigated the effects of increasing CuO NP concentration on the performance of biocomposite films derived from taro starch and Aloe vera gel. The CuO NPs were synthesized through chemical co‐precipitation, and calcification was mixed with taro starch and Aloe vera gel to obtain biodegradable bio‐nanocomposite films. The glycerol, biopolymers and CuO NPs were combined to produce a homogenous film by solvent casting and oven drying. The bio‐nanocomposite film was characterized by optical, mechanical, physical, chemical and morphological analysis as well as antimicrobial and antioxidant properties. Results show that as the concentration of CuO NPs increases, the film's opacity also increases as the film absorbs more light. Although the optimum percentage of CuO NPs enhanced the film thickness, the tensile strength decreased at higher concentrations (1.5% and 2.0%) due to agglomeration. Moreover, adding the CuO NPs to the biopolymer matrix had no new chemical interaction. However, the agglomeration was caused by physical factors. The glass transition temperature (Tg) and melting temperature (Tm) increase to 65.75°C and 48.38°C, respectively, which establishes enhanced thermal stability and good CuO biopolymer interaction. The antimicrobial activity significantly increased with CuO loading, showing a zone of inhibition of 15.8 mm against E. coli and 17.3 mm against S. aureus at 2.0% CuO NP concentration. Nevertheless, there was no significant change in antioxidant properties (DPPH and FRAP). These results show that the addition of 1.5% of CuO NPs gives a balanced combination of mechanical, thermal and antimicrobial properties, and hence taro starch and A. vera gel blend bio‐nanocomposite films could be a promising solution for active food packaging applications.