Keywords: strawberries, calcium dips, heat treatment, postharvest life, strawberry quality, fruit quality, surface damage, visual appearance, firmness, weight loss, fungal decay, colour changes
Effect of calcium dips combined with mild heating on postharvest life and quality of strawberry
The effect of calcium dips combined with mild heat treatment on quality and postharvest life of strawberries (cv. BARI strawberry–1) was studied. Immediately after harvest, strawberries were treated by dipping in distilled water, CaCl2 solutions at 1%, 2% and 3% for 15 min at 45°C and left untreated. Subsequently, the fruits were stored at 10°C with 80 ± 5% RH for 8 days. The effectiveness of the treatments was assessed by evaluating their impact on surface damage, quality attributes and overall visual appearance. Dipping strawberries in 1% CaCl2 solution at 45°C was the most effective treatment for decreasing surface damage, maintaining better firmness, reducing weight loss and delaying both fungal decay and external colour changes compared to 2 and 3% CaCl2 or other treatments. To a lesser extent, titratable acidity and pH were also affected by calcium dips. Considering the surface damage and firmness data, the postharvest life of 1% CaCl2–dipped strawberries was noted eight days whilst it was four to five days in other treatments. Moreover, 1% calcium dips increased the nutritional value by incrementing 31% of calcium content which did not affect the sensorial quality of fruits.