Impact of post-harvest chemical dipping and wax coating on taste and aroma of the apple fruits infected with sooty blotch and fly speck disease complex

Abstract

Sooty blotch and flyspeck are the two economically important diseases of apple that downgrade the fruits to an unmarketable extent, even just prior to harvest. Calcium hypochlorite (5%), calcium chloride (4%), sodium hypochlorite (3%) along with borax (1%), sodium hypochlorite (3%) with sodium bicarbonate (1%) and controls with and without treatment with water were evaluated as postharvest dips followed by rubbing and coating or non-coating. Wax Shool (1:1) and disinfectant Virosil-Agro (2.5%) were used as test coating materials. Calcium hypochlorite and calcium chloride treated fruits achieved maximum taste scores of 3.07 and 2.87 per cent compared to 1.95 and 1.80 scores awarded to water dip and no dip treatments, respectively. Coatings also increased the taste score from 2.25 recorded in uncoated fruits to 2.47 in Virosil-Agro and upto a maximum of 2.89 in Wax-Shool coated treatment. With regard to aroma, calcium hypochlorite treatment was awarded maximum aroma score of 3.04 compared to 2.54 to 2.77 values scored for rest of the test chemicals. Furthermore maximum aroma score of 2.72 was awarded to Wax-Shool and 2.49 Virosil-Agro treated fruits compared to a value of 2.14 for uncoated fruits.