Influence of microwave heating time on the structure and properties of chitosan films

Abstract

The aim of this study was to investigate chitosan film behavior during microwave heating for 10 different heating times from 0 to 40 min. Chitosan films were produced by casting. Their structure and properties were investigated with several techniques, including Fourier transform infrared spectroscopy and differential scanning calorimetry, but also by the measurement of the film color and the mechanical properties or by the study of the rheological properties of the rehydrated films. An original technique of gas chromatography (electronic nose) was used to analyze the film odor and highlight the presence of volatile compounds related to the Maillard reaction occurring during film heating. The results show that structural modifications occurred in two steps; this affected the polymer structure, such as the crystallization and chain scission. The appearance of the neoformed compounds was also observed and must be controlled to guarantee the safety of this food-contact packaging material.

Mechanical and moisture barrier properties of corn distarch phosphate film influenced by modified microcry stalline corn straw cellulose

“…In particular, it has thermoplastic characteristics that enable it to be processed easily, and it has been used as a very useful ingredient and additive in many industries . However, the physical properties of starch are worse than synthetic polymers, and it has some drawbacks, such as being highly hydrophilic, a poor water vapor barrier, and poor stability . These properties can be improved by physical, chemical, and enzyme modification methods .…”

“…Previous studies have shown the mechanical properties and barrier properties of the edible films are improved by exposing samples to high temperatures . In addition, the film solution is more uniform and smooth with high rapid heating . Nowadays, ultrasonic/microwave‐assisted treatment is widely used in the extraction and synthesis of components, and it is beneficial for improving the properties of edible films .…”

“…2,3 However, the physical properties of starch are worse than synthetic polymers, and it has some drawbacks, such as being highly hydrophilic, a poor water vapor barrier, and poor stability. 4 These properties can be improved by physical, chemical, and enzyme modification methods. 5,6 Incorporation of phosphorus into the structure of the starch is one of the most often applied such modification, and the functional properties of this biopolymer are changed obviously.…”

“…14 In addition, the film solution is more uniform and smooth with high rapid heating. 4 Nowadays, ultrasonic/microwave-assisted treatment is widely used in the extraction and synthesis of components, 15 and it is beneficial for improving the properties of edible films. 16 However, the study of modified microcrystalline corn straw cellulose (MMCSC) by ultrasonic/microwave-assisted treatment and the effect on the properties of corn distarch phosphate (CDP)-based films has not been reported.…”

Effects of ultrasonic/microwave-assisted treatment on the properties of corn distarch phosphate/corn straw cellulose films and structure characterization

“…Furthermore, improvement of the performance of edible film via ultrasonic treatment has been demonstrated, e.g., enhanced intermolecular forces, formation of a dense structure, elimination of air bubbles and easy vacuum degassing (Wang et al 2014b). Microwaves offer a fast and convenient method for heating, resulting in the breakage of hydrogen bonds and strengthening of the intermolecular crosslinking interactions (Jacquot et al 2014). Currently, ultrasonic/microwave-assisted treatment is widely used in the extraction and synthesis of components, the advantages of the proposed method being high extraction efficiency and solvent-free extraction (Feng et al 2014), and rarely used to improve the performance of protein edible film (Wang et al 2014b).…”