Improvement of the Shelf Life in ‘Honeycrisp’ Apples (Malus domestica Borkh.) using Hexanal

Abstract

In this study the effects of hexanal, a potential postharvest preservative, contained within ‘Enhanced Freshness Formulation’ (EFF), on apple ripening was investigated. EFF was sprayed before harvest on ‘Honeycrisp’ apples in commercial orchards within the Niagara region of Ontario, and its impact on ripening was compared to EFF without hexanal, EFF with calcium chloride and a control treatment in a randomized complete block design. There were no significant differences among treatments in fruit retention and most fruit quality measurements. However, there was an increase in TSS and a reduction of bitter pit in apples treated with EFF and EFFCA. Gene expression levels were evaluated for 18 genes that could be affected by hexanal application. EFF application reduced gene expression levels of phospholipase-D (PLD), ethylene, cell wall and calcium related genes. These findings suggest that hexanal plays an important role in the slowing of ripening throughout the shelf life of ‘Honeycrisp’ apples.