Antimicrobial Efficacy of Nanochitosan and Chitosan Edible Coatings: Application for Enhancing the Safety of Fresh-Cut Nectarines

The growing demand for fresh foods, as well as the rise in ready-to-eat foods, is leading the food industry to study edible coatings to maintain the quality of fresh-cut fruit. The objective of this work was, first, to determine the antimicrobial activity of a commercial anti-browning solution (A), chitosan (CH), and nanochitosan (NCH) both in vitro and in vivo and, secondly, to assess the effects of those coatings on the quality of fresh-cut nectarines. Antimicrobial activity was studied against Listeria monocytogenes and Saccharomyces cerevisiae, which were used as models of a foodborne pathogen and a spoilage microorganism, respectively. After evaluating their effect against both microorganisms, including in nectarines (Prunus persica L. cv Nectagala), the fruit was treated with commercial anti-browning alone (A), anti-browning with chitosan (A + CH), and anti-browning with nanochitosan (A + NCH). The slices were then sealed in polyethylene plastic trays and stored at 5 °C for 6 days. pH, titratable acidity, soluble solids content, firmness, color, visual acceptance, and microbiological evolution were assessed. Total color difference (TCD) results demonstrated higher value in the fresh-cut fruit without coating. The chitosan coating controlled microbial growth during cold storage without causing significant alterations to the fruit’s quality, while it had the highest overall visual acceptance of the final product. Chitosan demonstrated clear advantages as an edible biocoating for fresh-cut nectarines, whereas nanochitosan did not perform as effectively as expected, indicating the need for further optimization to realize its potential benefits. The combination of chitosan and anti-browning agents presents a sustainable method for enhancing the quality and safety of fresh-cut nectarines, which may contribute to the extension of their shelf life