Assessing Changes in Aroma Volatiles As Predictors of Chilling Injury Development during Peach (Prunus persica L. Batsch) Cold Storage and Subsequent Shelf-life

As peaches ripen and deteriorate quickly, cold storage is used to extend their marketability. However, peach cold storage is limited by the development of physiological disorders, such as chilling injury (CI), that express during subsequent shelf-life. The aim of this research was three-fold: first, to determine CI incidence in the melting flesh ‘Red Haven’ peach stored at different temperatures throughout postharvest; secondly, to characterize and compare differences among these fruit with regards to ethylene production rates, physicochemical properties, flesh texture, and aroma volatile profiles; and thirdly, to assess correlations among CI incidence and all the evaluated features, and identify potential key aroma volatile compounds that could predict early stage peach CI development during storage. Fruit were harvested at optimal maturity and stored at 0 °C, 5 °C, and 20 °C for up to 30 d. Evaluations were conducted at harvest (0) and after 1, 3, 5, 15, and 30 d of storage, with and without 3 d shelf-life period. Fruit stored at 5 °C were sensitive to CI displaying impaired capacity for ethylene production, and alterations in fruit textural properties, including reduced expressible juice contents and failure to soften. Chilling-injured fruit decreased accumulation of fruity note lactones, esters and terpenoids (i.e., linalool), and increased production of aldehydes and alcohols, as compared to sound fruit. Furthermore, multivariate regression identified thirteen potential key volatiles that could predict peach CI. These volatiles could be used as markers to discriminate chilling-injured from sound fruit at early stages of development of the disorder, optimizing cold storage and fruit handling practices, while decreasing loss and waste.