Ozonated Wash Water for Inhibition of Pectobacterium carotovorum on Carrots and the Effect on the Physiological Behaviour of Produce

Summary In postharvest the risk of produce losses due to mechanical injuries during harvest and handling, and to contamination with phytopathogenic microorganisms is very high. Root vegetables such as carrots are washed before packaging to remove inorganic and organic debris and to present the product appealingly. Hence, effective disinfection of the washing water is indispensable to eliminate the risk that carrots strongly loaded with microorganisms might infect previously uncontaminated tap roots. During the last few years, the addition of various sanitizers has been considered one of which is ozone. Ozone is highly bactericidic and fungicidic, and does not generate hazardous residues. On the other hand, ozone is a strong oxidant and might damage the produce. The aim of this study was to investigate the suitability of ozonated wash water for the assurance of carrots’ quality and safety stored at 20 °C during 10 days. Both in solution and on carrots, ozonated water effectively inactivated Pectobacterium carotovorum, a bacterium which causes the soft rot. On the other hand, washing carrots with ozonated water (ozone concentration: 4 ppm) for 2 min did not affect the physiological activity of the products. Hence, ozonated water can be recommend as a rather easily applicably and efficient sanitizer for the washing of root vegetables.