Decontamination of fresh-cut broccoli with a water–assisted UV-C technology and its combination with peroxyacetic acid

Abstract

The effectiveness of a water-assisted UV-C (WUV) technology for the decontamination of fresh-cut broccoli fromconventional and organic agricultural practices was evaluated as an alternative to chlorine sanitation. SeveralWUV doses (0.3–1.8 kJ m−2) were tested alone or combined with peroxyacetic acid (PAA). Results showed that0.5 kJ m−2was sufficient to reduce natural total aerobic mesophilic microorganisms by 2 log10in conventionalbroccoli without negative consequences on the physical quality. However, in order to achieve the same effect onorganic broccoli, a combined application of at least 0.3 kJ m−2and 50 mg L−1PAA was required. Total anti-oxidant capacity (TAC) was enhanced by 42, 90 and 81% in conventional broccoli 24 h after treatment with 0.3,0.5 and 1.8 kJ m−2, respectively, compared to water-control. A similar trend was observed in organic broccoli,although the increase in TAC (by 22%) compared to the water-control was only significant when a dose of1.8 kJ m−2was used. Similarly, 0.5 kJ m−2enhanced the sulforaphane content in conventional broccoli by 1.5and 4-fold compared to water and chlorine-controls, respectively. WUV is a promising alternative technology toimprove the microbiological and nutritional quality of fresh-cut broccoli.