Double-bottom antimicrobial packaging for apple shelf-life extension.

A package was created that extends apple shelf-life by slowing Penicillium expansum growth. The package consisted of a peelable lid and a tray with a double bottom with inclusion complexes (ICs) of ß-cyclodextrin (ß-CD) containing the essential oils of palmarosa (ICp) or of star anise (ICsa). Oil amounts required for antimicrobial activity were obtained from in vitro assays. After 12 days at 23 °C, P. expansum-inoculated apples in both of the double-bottom antimicrobial packages (DBAP) had 1/3 less fungal growth, less than 50% weight loss and ethylene and CO2 production, and less than 25% firmness loss, TA and SSC increase, and pH decrease compared to controls. The DBAP with ICsa performed better than with ICp in reducing ethylene production, respiration rate, firmness loss, TA increase, and pH decrease. This demonstrates DBAP containing ICp or ICsa can maximize the shelf-life of apples injured by P. expansum, validating a novel type of antimicrobial packaging.