Utilization of essential oils alone or incorporation with edible films is an appropriate technique to conserve the quality attributes and reduce post-harvest deterioration in fresh vegetables and fruits. Strawberries, being perishable fruits have a short shelf life, and using essential oils is considered one of the most suitable methods to prolong their shelf life during storage. The current study assessed the impact of different essential oils, including lemon oil (L), orange oil (O) and mandarin oil (M) on the physicochemical and microbial load of strawberries (Fragaria × ananassa cv. Festival) stored at 2 ± 1 °C and 95% relative humidity (RH) for 18 days. The differences in the physicochemical and microbial properties of strawberries were assessed by determining the following parameter changes: weight loss, decay percentage, firmness, soluble solids content, titratable acidity, color, anthocyanins, vitamin C, total phenol, total antioxidant, catalase activity, polyphenol oxidase activity, sensory evaluation, microbial content, total coliforms, molds, and yeasts. The results of this study indicated that the fruits treated with all essential oils treatments (L, O and M) had higher total antioxidant content and physicochemical properties than untreated fruits, due to protection against the microbial growth of molds, and yeasts. At the end of the storage period, the treated fruits showed a greater acceptance and sensory attributes than the untreated fruits. Furthermore, the correlation study showed a significant and negative relationship between the total antioxidant of treated fruits and following quality attributes including, weight loss, decay percentage, respiration rate soluble solids content, polyphenol oxidase activity, molds, and yeasts. It is noteworthy that all the essential oil treatments extended the shelf-life of strawberries and delayed their deterioration up to 18 days.
Effects of hot-water and steam blanching of sliced potato on polyphenol oxidase activity
