Quality Evaluation of Fresh Papaya Fruits Stored in Evaporative Coolers

A study was conducted to assess the performance of evaporative coolers for the storage of fruits and vegetables. The evaporative coolers used for this study consist of double-walled rectangular brick construction (1.29 × 2.55 × 2.56) m external and (1.13 × 1.27 × 2.08) m, internal, (length × width × height) with the inter-space filled with river bed sand saturated with water. In this study, ambient storage temperature ranged from 26.6 to 28.7oC with relative humidity which ranged from 64.7 to 85.2 percent. However, NBBEC storage recorded lower temperature within the range of 24.3 to 25.3oC and relative humidity which ranged from 88.8 to 91.2 percent while ABBEC storage recorded the least temperature which ranged from 23.0 to 24.1oC with highest relative humidity which ranged from 91.4 to 92.8 percent. The papaya fruits stored in the coolers and in ambient were evaluated for weight loss, total soluble solids, pH, total titratable acidity, ascorbic acid, beta carotene content and microbial load. TTA, ascorbic acid, beta carotene decreased; while pH and TSS increased with storage period. In ambient storage, fresh papaya fruits stored in evaporative coolers have lower microbial load compared to ambient storage with aluminum cladding of the cooler (ABBEC) further improving microbial quality and shelf life. The pawpaw fruits stored in the aluminum cladded burnt-clay-brick evaporative cooler (ABBEC) remained fresh and firm for ten days compared to three days in non-cladded burnt-clay-brick evaporative cooler (NBBEC) and four days in ambient storage.