Sodium caseinate-starch-modified montmorillonite based biodegradable film: Laboratory food extruder assisted exfoliation and characterization

• Published in: Food packaging and shelf life Vol. 15; pp. 17 - 27
• Main Authors: Kumar, Mukesh, Panjagari, Narender Raju, Kanade, Pavan Prakash, Singh, Ashish Kumar, Badola, Richa, Ganguly, Sangita, Behare, Pradip Vishnu, Sharma, Rajan, Alam, Tanweer
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.03.2018
• Subjects: Biodegradability; Bionanocomposite; Food extruder; Nanoclay; Overall migration; Sorption isotherm; Overall migration; Food extruder; Bionanocomposite; Biodegradability; Nanoclay; Sorption isotherm
• ISSN: 2214-2894; 2214-2894
• DOI: 10.1016/j.fpsl.2017.12.008

The present work aims at using a laboratory food extruder for exfoliating starch-montmorillonite (nanoclay) blend and uses the extrudate for blending with sodium caseinate for developing a bionanocomposite film (OP). Exfoliation of nanoclay was confirmed by TEM and XRD pattern. SEM revealed that surface of OP film was rough. Nanoclay addition had significant effect on tensile strength, elongation at break, water sorption and solubility of the film. Glass transition temperature of OP film was 44 °C. Moisture sorption isotherm was found to be of type-II with a typical sigmoid shape. FTIR spectra revealed that formaldehyde and nanoclay caused minor changes and the film was completely biodegradable within 114 h. Overall migration into n-heptane was found to be lowest among all food simulants. It was concluded that laboratory food extruder could be used to achieve exfoliation of nanoclay and develop a bionanocmposite film. •TEM and XRD pattern confirmed exfoliation of nanoclay in corn starch-nanoclay extrudate.•Glass transition temperature of developed bionanocomposite film was 44 °C.•Nanoclay addition had significant effect on tensile strength, elongation at break, water sorption and solubility of the film.•Bionanocomposite film was completely biodegradable within 114 h.•Nanoclay incorporation increased elongation at break while decreased WVTR.