Abstract

Potential of Natural Antimicrobials for the Production of Minimally Processed Fresh-Cut Apples

Lorenzo Siroli, Francesca Patrignani, Diana I. Serrazanetti, Giulia Tabanelli, Chiara Montanari, Silvia Tappi, Pietro Rocculi, Fausto Gardini and Rosalba Lanciotti

Background: Minimally processed fruit are susceptible to microbial spoilage and loss of sensory quality. In this experimental work, in order to increase the shelf-life and to maintain quality parameter (texture and colour) of sliced apples (Malus communis, var. Golden delicious), the use of natural antimicrobials was proposed.
Materials and methods: Natural antimicrobials were purposed to produce fresh-cut apples. Hexanal, citral, and combinations of hexanal+citral, citron essential oil+carvacrol, citral+2-(E)-hexenal, citral+citron essential oil and hexanal+2- (E)-hexenal were used in dipping step. After treatment, sample were stored at 6°C in ordinary atmosphere. During storage, yeast and lactic acid bacteria were monitored. Also volatile and electronic nose profiles, colour and texture analyses were considered. The samples were compared with a control (apples dipped in ascorbic and citric acid solution).
Results: Yeast cell loads showed that natural antimicrobials changed naturally occurring yeast growth parameters. The combination of citron+carvacrol prolonged the yeast lag phase of 6 d comparing with control, while citral and hexanal+2-(E)- hexenal decreased the maximum reached yeast cell load and growth rate, respectively. After 8 d, samples with hexanal+2-(E)- hexenal and citral showed equivalent or even better quality attributes compared to the controls, suggesting that this approach is a useful tool for fresh-cut apple production.
Highlight: Natural antimicrobial can be useful for the dipping of minimally processed apples Citral and hexanal+2-(E)-hexenal prolonged the apples shelf-life.
Apples treated with Citral and hexanal+2-(E)-hexenal had good quality attributes.