Bitter pit incidence and quality as influenced by post harvest application of calcium chloride in red and golden delicious apples

Bitter pit is a serious physiological disorder in apples affecting their marketable value and resulting in a considerable economic loss. An experiment was conducted to develop a suitable postharvest technique to reduce this malady. Physiologically mature fruits of Red and Golden Delicious apples were treated with 0 (T1), 2.0 (T2), 4.0 (T3), 6.0 (T4) and 8.0 (T5) per cent solutions of CaCl2 for 15 minutes and stored for 3 months at ambient temperatures. Fruits were analyzed for incidence of bitter pit and various other quality parameters viz physiological loss in weight (PLW), fruit firmness, total soluble solids (TSS), titrable acidity and sugars. Levels of Ca, Mg and K were also determined in the healthy and pitted tissues of untreated control fruits. The extent of bitter pit incidence varied with cultivars. ‘Red Delicious’ apples showed less incidence (7.5%) as compared to ‘Golden Delicious’ apples (12.3%). This can be attributed to a high level of Ca in ‘Red Delicious’ and a low level of calcium in ‘Golden Delicious’ apples at harvest. 2% CaCl2 was found sufficient in reducing bitter pit and maintaining the quality of ‘Red Delicious’, whereas 4% CaCl2 was effective in case of ‘Golden Delicious’.