Improving ready‐to‐eat apple cubes' safety using chitosan‐based active coatings

Abstract

The use of active coatings is shown as an option to offer safe ready-to-eat fruits and respond the growing demand of consumers for fresh, environmentally friendly and products free from chemical preservatives. In this work, chitosan (Ch), chitosan + vanillin (Ch-V), and chitosan + geraniol (Ch-G) coatings were applied on apple cubes to evaluate their microbiological quality for 12 days of refrigerated storage. All combinations applied demonstrated significant bactericidal effects on native microbiota, resulting in number of mesophilics, psychrotrophics, and yeasts and molds under the detection limit (<2.00 log) immediately after coating and during 12 days for most of them. Moreover, Escherichia coli O157:H7 and Listeria innocua artificially inoculated on apple cubes showed great reductions after coating treatments, exerting vanillin or geraniol enriched coatings outstanding antimicrobial activity. In fact, after 12 days of refrigerated storage, apple cubes treated with vanillin and geraniol (>2.00 log CFU/g) showed reductions in E. coli O157:H7 counts greater than 2.00 log in comparison with the control (4.68 log CFU/g). The preliminary results of this study demonstrated that Ch, Ch-Va, and Ch-Ge could be an interesting alternative to improve the safety of apple cubes and, therefore, a novel option to offer safe, ready-to-eat apple to consumers.