Development and Performance Evaluation of a Mobile Solar-powered Cooling System for Post-harvest Preservation of Oranges

A mobile solar cooling system (MSCS) for fruits and vegetables of 0.2 m3 was designed and fabricated in order to overcome the deficiencies in handling, distribution systems, processing and storage methods which significantly added up to post-harvest losses of oranges especially in regions with limited access to grid electricity. The performance evaluation of the MSCS was specifically carried out with sweet orange fruits. The experimental design used was a 2 by 3 factorial complete randomized block design. The Coefficient of Performance (COP) of the system was assessed through various parameters including cooling demand and energy consumption by the compressor and was calculated to be 2.02. The effect of the storage using the MSCS compared with ambient was done. The quality assessment tests of the stored oranges that were carried out include changes in physiological weight, sample rottenness, colour change and firmness. The determination of the chemical and microbial quality of the test samples as affected by the storage environment was also carried out. Storage temperatures and relative humidities recorded were (30 ± 6°C) and (78 ± 19%), (14 ±4°C) and (85 ± 10%) for ambient and MSCS respectively. The results of storage data were statistically analyzed using IBM SPSS statistics 25. The statistical results were highly significant among all the observations at probability level of (P<0.01). Results indicated that increase in storage temperature and time increases the chemical compositions in the stored oranges, except for acidity, fruit firmness and vitamin C that were decreased with the increase of storage time. Besides, MSCS increases the shelf life of the stored oranges for 33 days as compared to storage under ambient which is stored for 20 days. The results of this study has provided valuable insights into the potential benefits of using mobile solar-powered cooling systems for fruit and vegetables preservation.