This study is focused on optimizing, by surface response methodology, the mixture of natural additives:
nisin (an antimicrobial peptide) in combination with avocado seed or avocado peel extracts (both with
antioxidant capacities) in order to maximize the antioxidant activity and antimicrobial response against
some food-borne bacteria such as Listeria. The peel or seed extracts used in the mixture showed radical
scavenging capacity and antioxidant activity due to their polyphenol composition, including kaempferide,
epicatechin, chlorogenic acid, epicatechin gallate, among others. During optimization, the results
showed that the major antioxidant response in the mixture was mainly provided by the peel extract
compared with nisin, seed and their combinations in different proportions. In the antimicrobial response,
a synergic effect was observed in the mixtures of each avocado byproduct extract with nisin. Maximum
antioxidant and antimicrobial response were obtained with the mixture of 61% of peel extract with 39%
of nisin (p < 0.5, desirability 0.76) at concentrations of 1 mg/mL for each.