PLA Films Loaded with Green Tea and Rosemary Polyphenolic Extracts As an Active Packaging for Almond and Beef

In the present study, RE presented higher antioxidant capacity and higher content of total phenolic compounds than GTE. While the main phenolic compounds identified in RE were carnosic acid, carnosol and rosmarinic acid, in GTE catechins, rutin and gallic acid were the main identifies compounds. Extracts were incorporated into PLA active films, followed by the evaluation of its properties. The potential of the active PLA films to extend foods shelf-life was tested in almonds and beef. PLA/4GTE presented the highest water vapor permeability and opacity, while PLA/4RE presented the highest O2 permeability. PLA/2 GTE and PLA/4GTE presented the highest total content in phenolic compounds at the end of 10 days (at 40 °C). Regarding the almond packaged with the active films, PLA with RE films were the most effective in the reduction of oxidation, allowing to obtain the lowest lipid oxidation products, at the end of 60 days of storage at room temperature. In addition, active PLA films inhibited the formation of MDA content in beef stored for 11 days. This study shows that these PLA active packages can contribute for delaying lipid oxidation in foodstuffs with high fat content.