Aloe ferox gel-based coating alleviated rind pitting disorder and maintained quality attributes in ‘Kinnow’ mandarin subjected to simulated export and retail conditions

Rind pitting disorder (RPD) development in ‘Kinnow’ mandarin at ambient conditions after lower temperature storage or during shipping conditions is of major concern since it affects the fruit’s overall quality and shelf life and thus reduces its market value. This study evaluated the potential application of newly formulated Aloe ferox gel (AFG) edible coatings to alleviate RPD and maintain quality in ‘Kinnow’ mandarin fruits during cold storage and shelf life conditions. Fruit were coated with 30%AFG and 50%AFG, whereas uncoated fruits were used as the control. After coating, the fruit were stored at 5±1°C for 6 weeks (42 days). Analysis was conducted every two weeks of cold storage at 5±1°C and 80-85% (RH) and 3 days shelf life at 21±1°C and 50-55% (RH). Results showed that treatments had a significant effect (p>0.001) on rind pitting, respiration rate and citrus colour index. Coated fruit had an overall lower rind pitting incidence than uncoated fruit. Both 30%AFG and 50%AFG had an overall lower cumulative pitting incidence of 5.56%, while control experienced the highest pitting incidence of 66.66%. Fruit showed a lower respiration rate for 30%AFG than 50%AFG and control. Coated fruit showed a constant citrus colour index throughout storage compared to control fruits. These results show that AFG edible coating inhibited the processes associated with rind pitting and minimized metabolic processes that accelerate senescence in ‘Kinnow’ mandarin and thus reducing rind disorders and maintaining fruit quality. Overall, AFG, especially 30%AFG, could potentially be used as postharvest edible coating to control the development of rind disorders and conserve the quality of ‘Kinnow’ mandarin.