Use of Safe Substances as Additives for PVC Films and Their Effect on Enzymatic Browning of Gala Apples

Abstract

Some additives used in polymeric products can cause health problems; thus, lowering migration of such substances from the polymeric matrix is of concern. Given that migration is sometimes inevitable, the use of safe additives is an alternative. This work demonstrates the viability of employing generally recognized as safe (GRAS) substances (citric acid, vitamin C, and vitamin E) on PVC films plasticized with epoxidized waste cooking oil. The prepared films presented good mechanical properties, and in a few cases even exhibited improvements in properties such as increase in tensile strength and decrease in water vapor permeability. The films promoted a significant reduction in browning of refrigerated apple samples. The vitamin C-laden film was the most effective, being able to diminish apple browning even at room temperature. Among the tested additives, citric acid was the most effective in terms of protective action against oxidation, preventing degradation of procyanidin B2, caffeic acid, and epicatechin.