[4-1330-A] Postharvest/Food Technology and Process Engineering (2)

[4-1330-A-01] Edible Coatings Control Shrivel and Maintain Quality of Nectarines during Simulated Export Conditions

Shannon Riva², *Olaniyi Amos Fawole¹, Umezuruike Linus Opara^1,2 (1. Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Food Science, Stellenbosch University(South Africa), 2. Postharvest Technology Research Laboratory, South African Research Chair in Postharvest Technology, Department of Horticultural Science, Stellenbosch University(South Africa))

Keywords:Weight loss, ‘August Red’, Shrivel, Postharvest, Respiration rate

Nectarines are considered as one of the most important stone fruits of temperate origin. The fruit’s perishable nature, however, limits its commercial success; fruit is often exposed to very long handling chains during export. Edible coatings have shown great potential in maintaining quality and extending shelf life of fresh produce, and thus their application to nectarines is worth investigating as a green postharvest solution. Nectarines (‘August Red’) were treated with alginate (2%), chitosan (1.5%), gellan gum (0.5%) and gum arabic (2%) coatings and stored at -0.5 ± 1 °C, 80 ± 5% RH for 35 days and then at 21 ± 1 °C, 95 ± 5% RH for 20 days, simulating the cold storage shipment period and commercial shelf life period, respectively. Fruit were assessed at intervals for weight loss, fruit firmness, and colour changes, as well as respiration rates and ethylene evolution. Physiological disorders such as shrivel occurrence were assessed, as well as decay. The investigated edible coatings showed different effects, with gum arabic having the most effective performance on the plums. Fruit coated with gum arabic had the least weight loss while the highest weight loss was observed in uncoated fruit. In addition, the coating prolonged storage life by delaying fruit ripening and decreasing respiration rate and ethylene production. Furthermore, shrivel incidence was significantly (p<0.05) lower in fruit coated with gum arabic (2%) compared to the uncoated fruit (50%). Overall, the results suggested that gum arabic coating of nectarines was most effective to extend the storage life of nectarines (‘August Red’) and could be investigated further for commercial application.