Effect of carboxymethyl cellulose concentration on physical properties of biodegradable cassava starch-based films

• Published in: BMC chemistry Vol. 5; no. 1; p. 6
• Main Authors: Tongdeesoontorn, Wirongrong, Mauer, Lisa J, Wongruong, Sasitorn, Sriburi, Pensiri, Rachtanapun, Pornchai
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 10.02.2011; Springer Nature B.V; BioMed Central Ltd; BioMed Central; BMC
• Subjects: Cassava; Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Confidence intervals; Food Science; Fourier transforms; Lipids; Materials science; Mechanical properties; Molecular weight; Permeability; Research Article; Spectrum analysis; Statistical analysis; Moisture Sorption; Cassava Starch; Starch; Differential Scanning Calorimetry Thermogram; Cassava
• ISSN: 1752-153X; 1752-153X; 2661-801X
• DOI: 10.1186/1752-153X-5-6

Background Cassava starch, the economically important agricultural commodity in Thailand, can readily be cast into films. However, the cassava starch film is brittle and weak, leading to inadequate mechanical properties. The properties of starch film can be improved by adding plasticizers and blending with the other biopolymers. Results Cassava starch (5%w/v) based films plasticized with glycerol (30 g/100 g starch) were characterized with respect to the effect of carboxymethyl cellulose (CMC) concentrations (0, 10, 20, 30 and 40%w/w total solid) and relative humidity (34 and 54%RH) on the mechanical properties of the films. Additionally, intermolecular interactions were determined by Fourier transform infrared spectroscopy (FT-IR), melting temperature by differential scanning calorimetry (DSC), and morphology by scanning electron microscopy (SEM). Water solubility of the films was also determined. Increasing concentration of CMC increased tensile strength, reduced elongation at break, and decreased water solubility of the blended films. FT-IR spectra indicated intermolecular interactions between cassava starch and CMC in blended films by shifting of carboxyl (C = O) and OH groups. DSC thermograms and SEM micrographs confirmed homogeneity of cassava starch-CMC films. Conclusion The addition of CMC to the cassava starch films increased tensile strength and reduced elongation at break of the blended films. This was ascribed to the good interaction between cassava starch and CMC. Cassava starch-CMC composite films have the potential to replace conventional packaging, and the films developed in this work are suggested to be suitable for low moisture food and pharmaceutical products.