Evaluating the effect of utilizing ultrasound and citric acid on the feasibility of producing biodegradable film based on lemon juicing waste

The lemon juicing waste encompasses valuable bio-components that stimulated the development of novel and biodegradable films. This study aimed to investigate the feasibility of producing biodegradable films from lemon waste powder (LWP) (1, 3, and 5%) and subsequently evaluate the effect of ultrasonic and citric acid solution on mechanical and physical properties (thickness, solubility, water vapor permeability (WVP), color changes, and transparency) of LWP-based film samples. According to the results, elevating the LWP concentration from 1 to 5% had led to an increase in the tensile strength, thickness and color changes remarkably and decreases the solubility, water vapor permeability, and transparency of the film samples. However, utilizing 5% LWP had resulted in a reduction of elongation at the break value of the film samples compared to the prepared films from 3% LWP. The results also revealed a significant effect of utilizing ultrasonic and citric acid in improving the mechanical and physical properties of the film samples. Therefore, utilizing ultrasound and citric acid in the production of biodegradable LWP-based films could improve the functional characteristics of films. In conclusion, the sample prepared from 3% LWP and treated by ultrasound and prepared with 1% citric acid was selected as an optimum film sample with a desirable physical, mechanical and barrier properties.