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This work is directed towards developing biodegradable films from biopolymer that is sustainable and environmentally friendly particularly tapioca starch (TPS) films. However, the usage of TPS films for food packaging application has been limited due to the poor mechanical, barrier and thermal properties. Microcrystalline cellulose (MCC) at different concentrations (0 to 10 wt.%) was incorporated as the filler into the films to form TPS/MCC composite films via solvent casting method in order to improve the limited properties of the films. The TPS/MCC films were characterized in terms of physical, mechanical, barrier, and thermal properties. Ot was found that 3 wt.% MCC was the ideal concentration of filler that resulted to the highest performance of the films in terms of mechanical and barrier properties. Thermal properties of the films were also improved with the addition of MCC into the films. On conclusion, TPS/MCC films produced in this study exhibit improved properties and have the potential to be used for food packaging application.

The usage of biopolymer as food packaging material has been limited due to high water sorption and poor mechanical properties of the biopolymer. Thus, this study is aimed at improving the water sorption and mechanical properties of biopolymer particularly starch films by incorporation of a natural filler particularly chitosan nanoparticle (CNP) and investigating the properties of starch/CNP films at different storage conditions (relative humidity: 23, 50, and 75%; temperature: 4, 30, and 40°C). The water sorption behavior and isotherms of the films were investigated by fitting the water sorption data to the Peleg model and Guggenheim, Anderson, and de Boer model. Both the models were well fitted to the experimental data, thus proving the reliability of water sorption behavior prediction. It was found that different storage conditions of the films significantly affected the mechanical properties of the films due to the sensitivity of the films towards moisture. Water sorption and mechanical properties of the films were best improved at relative humidity of 23% and temperature of 30°C. The water sorption and mechanical properties of the films are worth to be investigated because the properties affected the stability, shelf life, and application of the films in the food packaging field.

The mechanical, thermal, and barrier properties of tapioca starch films produced using a solvent casting method with varying concentrations of chitosan nanoparticles (CNPs; 5, 10, 15, 20, 25, 30, 35% w/w of solid starch) were investigated. The addition of 15% w/w CNP (size range: 20–50 nm) to the starch films (starch/CNP films) enhanced the tensile strength from 1.12 to 10.03 MPa (7.96-fold increment) and elongation at break from 67.00 to 90.77% (0.35-fold increment). However, the thermal stability of the starch films reduced slightly whereby the maximum degradation temperature decreased from 316.32 to 289.11°C (0.09-fold decrement) with the addition of CNP. The opacity of 15% w/w starch/CNP films increased from 8.07 to 14.67 due to the presence of CNP within the starch matrix that hinders the light transmission pass through the film. Furthermore, reductions in the water vapor permeability from 1.1 × 10−11 to 0.63 × 10−11 g/Pa h m (4-fold increment) and oxygen permeability from 7.38 × 10−3 to 3.59 × 10−3 cm3/m day Pa (0.51-fold increment) of the films were observed. Starch/CNP films fabricated in this work exhibit enhanced the mechanical and barrier properties, thus proving the promising potential to be employed as food packaging materials.

This work aims to develop corn starch/chitosan nanoparticles/thymol (CS/CNP/Thy) bio-nanocomposite films as potential food packaging materials that can enhance the shelf life of food. CS/CNP/Thy bio-nanocomposite films were prepared by the addition of different concentrations of thymol (0, 1.5, 3.0, 4.5 w/w%) using a solvent casting method. The resulting films were characterized in terms of optical, mechanical, and water vapor permeability (WVP) properties. The addition of thymol was found to reduce the tensile strength (TS), elongation at break (EAB), and Young’s modulus (YM) of the films. Generally, the increment in the concentration of thymol did not significantly affect the TS, EAB, and YM values. The addition of 1.5 w/w% thymol increased the WVP of the films but the WVP reduced with the increase in thymol concentrations. CS/CNP/Thy-3% bio-nanocomposite films demonstrated the potential to lengthen the shelf life of cherry tomatoes packed with the films, whereby the cherry tomatoes exhibited no significant changes in firmness and the lowest weight loss. In addition, no mold growth was observed on the sliced cherry tomatoes that were in direct contact with the films during 7 days of storage, proving the promising application of the films as active food packaging materials.