Filmes ativos produzidos com blendas de PVA em biopolímeros : desenvolvi- mento, caracterização e aplicação em massa fresca tipo pastel

Abstract

The food industry is responsible for 68% of the volume of plastic packaging consumed in the world, with synthetic polymers being the main source of this production. However, these materials generate negative impacts to the environment since they present small degradability to natural factors. As an alternative, the use of biopolymers has been explored for the development of biodegradable packaging. The polysaccharides of great interest in the food and pharmaceutical industry, chitosan and pectin, were used in the preparation of polymer blends for the production of biodegradable and active films. The films composed of chitosan: polyvinyl alcohol (70:30 and 60:40) and pectin: polyvinyl alcohol (30:70 and 20:80) were elaborated and characterized by SEM, FTIR and DSC techniques, and for the visual, water affinity, biodegradability, and mechanical properties. Later they were applied on the pastel masses and these were characterized as far as physical-chemical and microbiological aspects. The films of QUI70, QUI60 showed good behavior in water (angle 78 º, 30% soluble and CPVA of 1.4 x10-15 g / m.s.Pa-1). However, the pectin films presented a reduction of affinity for the less significant water, however, they stood out for the good aspects of elasticity and tearability of the films. Both films have good color and transparency aspects, and good biodegradability, about 35%. As for the microbial control, the active films of QUI70 and QUI60 showed high effectiveness in the control of mesophiles, reducing 1.8 log cycles. While the PEC20 film promoted an increase in the growth of the group of coliforms. The physicochemical aspects of the masses interspersed by active films of QUI70, QUI60, PEC30 and PEC20 were able to maintain the stability and quality of the product with pH around 6.0 and its maximum acidity of 1.2% and minimum Aw of 0.92. The texture aspects were equated with the commercial mass. It was concluded, therefore, that the development of films from chitosan blends: PVA and pectin: PVA by casting method is viable and has potential applications for the cake type fresh pasta industry.