Optimization of biocomposite taro (Colocasia esculenta (L.) Schott) starch and Aloe vera (Aloe barbadensis (L.) Burm.f.) gel based film-using response surface methodology

This study aimed to develop and optimize a biocomposite film using taro starch and aloe vera gel blends. A Single factor experiment followed by a three-factor Box-Behnken design (BBD) of response surface methodology (RSM) was used to optimize the film based on water vapor transmission rate (WVTR), tensile strength (TS), and thickness as response factors. Results showed that increasing taro starch content generally increased tensile strength but also increased WVTR. Meanwhile, aloe vera gel reduced the WVTR but had a less significant effect on TS. Glycerol worked as a plasticizer, decreasing the TS but significantly reducing the WVTR. The regression model's prediction was confirmed by characterizing the biocomposite film made using the optimal composition, which had water vapor transmission rate, tensile strengths, and thicknesses of 0.00163 g/m2t, 3.26 MPa, and 0.14 mm, respectively. This optimal composition is achievable with 5.56% taro starch, 49.25% aloe vera gel, and 25.00 % glycerol, resulting in a biocomposite film with low WVTR and moderate TS. The biocomposite film prepared using the optimized independent factors was also characterized by different analytical techniques such as Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), and Differential Scanning Calorimetry (DSC). The findings show that FTIR analysis detects the critical functional groups such as O H, C H, and C O that contribute to the biocomposite film's structure and properties. SEM analysis illustrates a rough surface, presenting dispersed particles and some cracks that reflect the mechanical properties of the film obtained. DSC showed that the biocomposite film exhibited a glass transition temperature and a gelatinization peak, highlighting the thermal behavior of the biocomposite film. Thus, the optimized biocomposite film can be a potential candidate for food packaging applications.