Physical properties of cassava starch–carnauba wax emulsion films as affected by component proportions

Properties of glycerol-plasticised cassava starch–carnauba wax emulsion films were studied as functions of carnauba wax/starch (CW/S) ratios. Increases in CW concentrations improved elongation, but impaired tensile strength and elastic modulus, suggesting a plasticising effect by CW and/or the emuls...

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Detalhes bibliográficos
Autores: Ito, Edson Noriyuki, Santos, Talita M., Pinto, Alaídes M. B., Oliveira, Ana Vitoria de, Ribeiro, Halisson L., Caceres, Carlos Alberto, Azeredo, Henriette Monteiro Cordeiro de
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2014
País:Brasil
Recursos:Universidade Federal do Rio Grande do Norte (UFRN)
Repositorio:Repositório Institucional da UFRN
Idioma:inglés
OAI Identifier:oai:repositorio.ufrn.br:123456789/41517
Acesso em linha:https://repositorio.ufrn.br/handle/123456789/41517
Access Level:acceso abierto
Palavra-chave:Biopolymers
Edible films
Food packaging
Lipids
Polysaccharides
Descrição
Resumo:Properties of glycerol-plasticised cassava starch–carnauba wax emulsion films were studied as functions of carnauba wax/starch (CW/S) ratios. Increases in CW concentrations improved elongation, but impaired tensile strength and elastic modulus, suggesting a plasticising effect by CW and/or the emulsifier. CW reduced water solubility of the films and decreased their water vapour permeability (WVP) up to CW/S ratios of 0.15–0.20, probably because of the decreased water solubility. Higher CW concentrations resulted in increased WVP, possibly due to starch matrix loosening. The opacity imparted by high CW concentrations in films could compromise some applications. The Tg of starch and the expected CW effects on it were not evidenced by DSC thermograms, but CW seems to have affected starch crystallisation, maybe by forming complexes with amylose and/or amylopectin