Effectiveness of Selected Cold Chain Management Practices to Extend Shelf Life of Mango Fruit

An on-farm study was conducted among smallholder mango farmers in Embu County of Kenya to demonstrate the effectiveness of simple harvest and postharvest handling practices to attain cold chain and extend mango shelf life. The recommended cold chain practices were compared with common farmers' practices. 'Apple', 'Ngowe', 'Kent', and 'Tommy Atkins' harvested at the mature green stage were used in the study. To demonstrate proper cold chain, fruits were harvested before 8 am, transported in crates lined with dampened newspapers, precooled in an evaporative charcoal cooler, and then transferred to a Coolbot™ cold room (10 ± 2°C). To demonstrate common farmers’ practices, fruits were harvested at noon, transported in open crates, and stored at ambient room conditions (25 ± 7°C, 55 ± 15%RH). The air and fruit pulp temperatures were monitored regularly using HUATO® data loggers. During the storage period, a random sample of 3 fruits (per variety) per treatment was taken after every 3 days to evaluate ripening related changes including physiological weight loss, colour, firmness, and total soluble solids. Proper cold chain practices resulted in low fruit pulp temperature (average 11°C) compared to 25°C for fruits handled using common practices by farmers leading to faster ripening as evidenced by lower peel/pulp colour and firmness, higher physiological weight loss, and higher total soluble solids. For example, flesh firmness of fruits under poor cold chain practices decreased from initial 36.6 N, 45.9 N, 66.5 N, and 46.8 N to 3.1 N, 2.4 N, 3.2 N, and 3.1 N for ‘Apple’, ‘Ngowe’, ‘Kent’, and ‘Tommy Atkins’ varieties, respectively, at the end of storage while that of fruits under proper cold chain practices reduced to 2.3 N, 1.5 N, 3.9 N, and 2.9 N, respectively, for the four varieties at the end of storage. Overall, proper cold chain management extended mango shelf life by 18 days. Application of simple harvest and handling practices coupled with simple storage technologies can attain and maintain the cold chain required to preserve quality and extend shelf life. This could increase the marketing and storage periods for later selling and processing, respectively, of mango fruits.