Il controllo in continuo dell'ozono e dell'Imazalil impiegati nella postraccolta degli agrumi. [On-line feedback control of ozone and Imazalil in postharvest of citrus fruits]

In this paper the results of plant set-up for Ozone treatments tin washing water and in cold storage room atmosphere) and on line imazalil solution concentration control during dip treatment of citrus fruit are presented. The feedback control system for both systems has been designed to control the active agent in the range ± 10% of set point. Both systems have been equipped with high precision measuring sensors (UV spectrometer for imazalil and uv analyzer for Ozone). Ozonized water fruit washing on the packing line resulted in low effectiveness due to contaminations during the subsequent operations (waxing, drying, grading, sorting, packing). The use of ozone in cold storage atmosphere using a concentration of 0.25 ppm reduced the fruit spoilage and enhanced the imazalil action. The on line control of Imazalil in water mixture for fruit dipping treatment resulted in lower residue levels in comparison with standard treatment (imazalil in wax) but fruit decay dramatically increase.