Effects of postharvest applications of calcium nitrate and acetate on quality and shelf-life improvement of "Jonagold" apple fruit

Abstract

The effects of postharvest application of calcium were investigated on shelf-life and quality of apple fruits (Malus domestica cv. ‘Jonagold’) after harvest or cold storage up to 150 days. The fruits were immersed in deionised water or in different calcium sources (calcium acetate at two calcium concentrations 0.35 and 0.7%w/v and calcium nitrate at two calcium concentrations 0.5 and 1%w/v. The experiment was carried out in 2010 to 2011 and fruit weight losses, fruit firmness, total soluble solids, pH, titratable acidity, total soluble solids /titratable acidity ratio, thiault index, perlim index, ethylene production, peroxidase and catalase enzyme activities were measured at 20, 40, 60, 80, 100, 120, and 150 days after harvest life. Results showed that all immersing conditions leaded to the best results of fruit quality assessments when compared with control. The calcium treatments increase fruit firmness, titratable acidity and catalase enzyme activity, while decreasing total soluble solids, weight losses percentages, ethylene production, TSS/TA ratio and Peroxidase enzyme activity during cold storage at 0-2°C for 150 days. Key words: Shelf-life, “Jonagold“ apple, calcium nitrate, calcium acetate.