Antimicrobial and antioxidant bionanocomposites and their potential applicatios in food packaging

Abstract

The search for alternatives to eliminate environmental problems caused by solid waste from synthetic polymers has raised the interest of the food industry and for research associated with biopolymer packaging. Linked to the environmental demand, society is increasingly searching for natural and healthy foods. In this sense the use of bionanocomposites becomes a viable possibility for the development of new active packages. This work aimed to develop active packaging with antimicrobial and antioxidant action for application in foods with high fat and moisture content. Bionicomposites of pectin biopolymer containing pracaxi seed oil nanemulsion and cellulose acetate were produced with a hybrid of nanoclay with essential oil of clove oil. The effect of the nanoemulsion on the water vapor barrier properties and activation energy, moisture sorption, contact angle, antioxidant properties and its application in butter samples was investigated. As for the cellulose acetate bionanocomposites, the water vapor barrier properties, optical and mechanical properties, antioxidant and antimicrobial activity were evaluated and the efficiency in cooked ham samples was evaluated. The results showed that the incorporation of the pracaxi seed oil nanoemulsions resulted in an increase in hydrophilicity and an increase in the amount of active sites on the surface. However, the nanoemulsion acts as a physical barrier against permeability. The antioxidant activity measured through total phenolic compounds (TPC), DPPH, phosphomolybdenum and beta carotene/linoleic acid was found that the addition of 0.4% m/m of pracaxi oil leads to an increase of 36%, 56%, 3.25% and 80%, respectively. The presence of antioxidant activity, mainly phenolic compounds, resulted in butter protection against oxidation during the 60 days of storage. The incorporation of 30% w/w hybrid of nanoclay and clove essential oil in cellulose acetate caused a reduction in permeability from 1.923±0.175 to 0.544±0.024. There was also a reduction in the mechanical properties of 68.69% in tensile strength and 107.95% in elongation at break. An inhibition against Escherichia coli , Listeria monocytogenens and Lactobacillus sakie strains was observed. The total phenolic compounds (TPC) varied from 1.64±0.10 mg GAEq to 103.77±0.25mg GAEq and antioxidant activity by DPPH method changed from 2.79% to 88.70% and an approximately 889 fold increase in antioxidant activity by phospholibdenium. In addition, when applied to samples of cooked ham, a lower microbiological load of ham (psychotrophs, mesophiles and lactic bacteria) was observed, the pH was kept stable during the whole storage period and the reddish color was preserved. Thus the use of active packaging from bionanocomposites is a favorable alternative to increase the shelf life of food products.