Postharvest Quality of Strawberry Fruit (Fragaria x Ananassa Duch cv. Albion) as Affected by Ozone Washing: Fungal Spoilage, Mechanical Properties, and Structure

Abstract

Storage life of strawberry fruit is limited due to its high softening rate and susceptibility to fungal attack. Thus, it is of interest to develop and improve preservation techniques to reduce postharvest losses. The aim of this study was to evaluate the effect of ozonized water washing (maximum concentration of 3.5 mg L−1; 5–15 min) on fungal spoilage, water loss, mechanical properties, and structure of strawberries (cv. Albion) harvested in different years and stored at 5 °C. The effect of ozone treatment on decontamination and weight loss was dose-dependent. Ozonization for 5 min significantly reduced fungal incidence (~ 22–25% lesser than control) and weight loss of strawberries throughout storage. High doses (10 or 15 min) did not reduce significantly fungal growth in relation to control, although weight loss in fruit treated for 15 min was higher than control. In both harvest years studied, cold storage provoked a diminution in deformability modulus and an increase in deformation but a significant effect of treatment was not observed. These changes were correlated with alteration of cell walls and turgor loss. Otherwise, cuticular membrane of strawberries treated for 5 min was observed thicker and more electron dense than in fruit ozonized for 15 min or control. It could partially explain the lower moisture loss observed in 5-min treated fruit. Results showed that ozonized water washing for 5 min can be an alternative strategy for extending postharvest strawberry shelf-life by decreasing fungal decay and water loss along cold storage, without affecting mechanical parameters.