Impact of gum arabic and sodium alginate and their interactions with whey protein aggregates on bio-based films characteristics

OSELLA, CARLOS A.; ERBEN, MELINA; ALVAREZ, VERA A.; PÉREZ, ADRIÁN A.; ERBEN, MELINA; SANTIAGO, LILIANA G.; ALVAREZ, VERA A.; OSELLA, CARLOS A.; PÉREZ, ADRIÁN A.; SANTIAGO, LILIANA G.

INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES

ELSEVIER SCIENCE BV

Año: 2019 vol. 125 p. 999 - 1007

0141-8130

Two polysaccharides (PS), gum arabic (GA) and sodium alginate (SA), and whey protein concentrate (WPC) were used to design bio-based films at two ratios (R PS:WPC 1:2 and 1:3). The effects of PS, R PS:WPC and WPC thermal treatment (unheated vs. aggregate) were determined on films characteristics. Film-forming dispersions were tested using different complementary techniques: UV?Vis spectroscopy, electrophoretic mobility, bulk rheology and confocal microscopy. PS exhibited weak associations with proteins. However, this behavior was more significative in SA/WPC systems. Rheological and optical characteristics of filmogenic suspensions were influenced by PS, R PS:WPC and WPC heat treatment. Apparent viscosity values for SA/WPC systems were 80-250 times higher than the ones obtained for GA/WPC systems. Furthermore, thickness, moisture absorption, contact angle and mechanical properties were also affected by the film design factors. GA/WPC-aggregates films showed lesser moisture absorption; however, they have higher surface polarity than those made with SA/WPC-aggregates. Moreover, SA/WPC-aggregates systems provided stronger films in comparison with the GA/WPC-aggregates ones. In addition, mechanical properties were also affected by R PS:WPC and WPC treatment. It was observed that denatured WPC and 1:3 R PS:WPC produced weaker mechanical features. Results provide useful information for the design of bio-based mixed films with tailor-made properties.