Produção e caracterização de filmes de zeína adicionados de casca e extrato da casca de pinhão

Abstract

The search for new techniques that product materials to replace plastic for food packaging, has led to an increased application of biodegradable polymers to form films and coatings. Zein is a protein insoluble in water, extracted from corn grain and a by-product at production of his starch, is a biopolymer that contains flexible films formation capacity, is biodegradable and can be used as active packaging. The use of natural fibers for enriching agents into biodegradable films has become usual, because their mechanical properties of those compounds. This study aimed to the production of zein films, enriched with pine nut shell and his extracts (aqueous, hydro alcoholic and ethanol). Were analyzed the mechanical properties (elongation at break, Young's Modulus and tensile strength), antibacterial, antioxidant capacity (DPPH, FRAP, Total Phenolic and ABTS) and heat (DSC) of the films and produced extracts. The results showed that the addition of hydro-alcoholic and ethanol extracts had similar values to the film control to the Young's modulus, since the film with aqueous extract showed elongation and tensile strength greater than the others, indicating greater tenacity. For DSC results of the films made of the control and pine shell had a glass transition temperature (Tg) higher than those found in the literature for zein, as compared with other plasticizers compounds. All films and extracts analyzed showed antioxidant capacity, with differences influenced by the type of solvent used in the extraction of phenolic compounds of the seed bark and their interactions with the polymer matrix of the zein. There was no antimicrobial action in the films under the Staphylococcus aureus and Escherichia coli. The zein films with addition of shell pine nuts and his extracts showed favorable characteristics for application as active packaging.