83B-8 |
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P. G. Veiga1, L. M. Oliveira2, A. J. Alves, Sr.3, M. P. Cereda4, and A. R. P. SCAMPARINI1. (1) Dept. of Food Science, Univ. Estadual de Campinas (UNICAMP), Cidade Universitária Zeferino Vaz, PO Box 6121, Campinas, Brazil, (2) Packaging Technology Center - CETEA, Food Technology Institute - ITAL, Av. Brasil, 2880, Campinas/SP, 13073-001, Brazil, (3) 3M do Brasil Ltda., Rodovia Anhanguera, km 110, Caixa Postal 123, Sumaré-SP, 13001-970, Brazil, (4) Centro de Raízes Tropicais - CERAT, Universidade Estadual Paulista, Botucatu/SP, 18603970, Brazil In order to improve cassava starch films mechanical and barrier properties, many additives have been studied. Although the effect of microbial gums in films has not been much studied xanthan gum and starch interaction could result in a tithed network structure material, which could improve mechanical and barrier characteristics. Not acetylated xanthan gum could result in an even closer structure. In previous works, sucrose also had demonstrated to be a feasible plasticizer for starch films. The influence additives on cassava starch films characterization were investigated by a 27-3 factorial design experiment with two statistical blocks, totalizing 19 experiments each, differing only by one variable (xanthan gum, acetylated or not). The other variables were: cassava starch, sucrose, propylene glycol, soy oil, sodium phosphate and pH. Mechanical parameters were investigated for elongation and tensile resistance (Universal Testing Machine INSTRON, 5500R) and hydrophilicity was analysed by contact angle measurements (VCA optima at 3M, BR). Water activity (DECAGON-CX-2/AQUALAB) was also investigated. Film elongation was lower (<1.5%) when using xanthan gums (acetylated or not) and higher (> 15.0%) for sucrose. However, sucrose resulted in lower tensile resistance (< 10.0%). Cassava starch concentration increased hydrophilicity; wile sucrose decreased such parameter, indicating that high sucrose and low cassava starch concentrations could increase the material water vapor barrier. Films water activity were not affected (p<0.05) by any variable investigated. The minor additives and pH did not influenced cassava starch films performance. Xanthan gum (acetylated or not) did not improve film protection characteristics, however, sucrose could be a low cost solution for increasing cassava starch films elongation. The authors would like to acknowledge CETEA-ITAL and 3M, from BR, for the technical support, and CNPq and FAEP-UNICAMP for financial support.
Session 83B, Food Packaging: Applications of edible coatings, antimicrobial films, and sensors in food packaging
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