Evaporative cooling can reduce outside air temperature to within a few degrees above the outside wet bulb air temperature.  It is particularly useful in temperate climates but is of some help even in many tropical areas.  If you are primarily cooling fruit slowly and storing it, the system should produce 0.03 m3/s-tonne.  If you are interested in fast cooling the airflow system should produce 0.3 m3/s-tonne.  In evaporative cooling systems the air is cooled by a wetted medium, passes by the warm product and then exhausted to the outside.  It is not recirculated.  Design details for the evaporative cooler can be found at a number of web sites discussing evaporative cooling for greenhouses.  You might try: http://edis.ifas.ufl.edu/AE069. –