Effect of pre-cooling, fruit coating and packaging on postharvest quality of apple

Freshly harvested apple fruits cv.'Royal Delicious' were subjected to Surface coating with 1, 1.5, 2% neem oil (Azadirachta indica) and 10, 15, 20% marigold flower (Tagetes erectus) extracts with pre cooling on apple storage quality was tested. Then the fruits were analyzed for physicochemical and physiological characters such as loss in weight, fruit firmness, total soluble solids (TSS) content, titratable acidity (TA), pH, reducing sugar contents, pectin, total anthocyanin, polygalacturonase (PG) activity and fruit spoilage. The results revealed that, the 1.5-2% concentration of neem oil as a surface coating along with pre-cooling was the most effective by retaining better physiochemical characteristics, in addition, significantly lowering disease incidence. Similarly, packaging of fruits with corrugated fiber board (CFB) boxes + paper mould trays, CFB + Polyethylene (PE) liners and shrink wrapped tray packing during storage (18-25 °C and 65-75% RH), revealed that 2% neem oil surface coating with shrink wrap tray packing resulted the better retention of storage life and, whereas, the treatment effect on physico-chemical characteristics of fruits were significant (p < 0.05). However, the treatment effect was statistically at par with the marigold extract application with shrink wrapped tray packing in pre cooled fruits (10-15 °C, 70-75% RH) during ambient storage (18-25 ° C, 65-75% RH).