Lettuce, tomatoes and carrots were evaluated under four disinfection methods. Chlorine (50, 100 and
200 ppm) was compared for effectiveness with citric acid (0.5, 1 and 1.5%), ultraviolet light (UV-C) (0.65
and 1.6 mW/cm2
) and ozone (5 ppm) to inactivate Escherichia coli ATCC 11775. Processing times were
from 3 min up to 60 min. Hunter color parameters, color functions (DE, hue, chroma), tomato color index
(TCI) and whiteness index (WI) were evaluated after disinfection. Results showed that citric acid was not
effective for inactivation of E. coli at the tested conditions. UV-C was effective in the inactivation of the
microorganism when fluence was higher, being more effective in the smooth surface of tomato (2.7 log).
Meanwhile, ozone was also able to inactivate bacteria in tomatoes (2.2 log) after only 3 min. Carrots and
lettuce showed lower inactivation for all treatments because of their porous and roughened surfaces. UVC
was the treatment that most affected the color of the produce; it generated browning of lettuce, and
increase of TCI and WI of carrots. Ozone also affected the greenness of lettuce. Concentration, dose and
processing times of novel disinfection methods need to be evaluated not only for microbial counts, but
also sensory properties
Lettuce, tomatoes and carrots were evaluated under four disinfection methods. Chlorine (50, 100 and200 ppm) was compared for effectiveness with citric acid (0.5, 1 and 1.5%), ultraviolet light (UV-C) (0.65and 1.6 mW/cm2) and ozone (5 ppm) to inactivate Escherichia coli ATCC 11775. Processing times werefrom 3 min up to 60 min. Hunter color parameters, color functions (DE, hue, chroma), tomato color index(TCI) and whiteness index (WI) were evaluated after disinfection. Results showed that citric acid was noteffective for inactivation of E. coli at the tested conditions. UV-C was effective in the inactivation of themicroorganism when fluence was higher, being more effective in the smooth surface of tomato (2.7 log).Meanwhile, ozone was also able to inactivate bacteria in tomatoes (2.2 log) after only 3 min. Carrots andlettuce showed lower inactivation for all treatments because of their porous and roughened surfaces. UVCwas the treatment that most affected the color of the produce; it generated browning of lettuce, andincrease of TCI and WI of carrots. Ozone also affected the greenness of lettuce. Concentration, dose andprocessing times of novel disinfection methods need to be evaluated not only for microbial counts, butalso sensory properties
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