Titanium dioxide/UV photocatalytic disinfection in fresh carrots

Mihee Cho, Yoonjung Choi, Hyojin Park, Kwansik Kim, Gun-Jo Woo, Jiyong Park

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

Increased occurrences of fresh produce-related outbreaks of foodborne illness have focused attention on effective washing processes for fruits and vegetables. A titanium dioxide (TiO2) photocatalytic reaction under UV radiation provides a high rate of disinfection. The photo-killing effects of TiO2 on bacteria in liquid cultures under experimental conditions have been widely studied. However, the disinfection effects of the TiO 2 photocatalytic reaction on fresh vegetables during a washing process have not been evaluated. Our objectives were to design a pilot-scale TiO2/UV photocatalytic reactor for fresh carrots and to compare the bactericidal effects of the TiO2/UV reaction against bacteria in liquid media and on carrots. TiO2/UV photocatalytic reactions for 40, 60, and 30 s were required for the complete killing of Escherichia coli, Salmonella Typhimurium, and Bacillus cereus (initial counts of approximately 6.7 log CFU/ml), respectively. The counts of total aerobic bacteria in fresh carrots and foodborne pathogenic bacteria in inoculated carrots were also measured. Counts of total aerobic bacteria were reduced by 1.8 log CFU/g after TiO2/UV photocatalytic disinfection for 20 min compared with a 1.1-log CFU/g reduction by UV alone. E. coli, Salmonella Typhimurium, and B. cereus (8 log CFU/ml) were inoculated onto carrots, and the number of surviving bacteria in carrots was determined after treatment. The TiO2/UV treatment exhibited 2.1-, 2.3-, and 1.8-log CFU/g reductions in the counts of E. coli, Salmonella Typhimurium, and B. cereus, respectively, compared with 1.3-, 1.2-, and 1.2-log CFU/g reductions by UV alone. The TiO2/UV photocatalyst reaction showed significant bactericidal effects, indicating that this process is applicable to nonthermal disinfection of fresh vegetables.

Original languageEnglish
Pages (from-to)97-101
Number of pages5
JournalJournal of Food Protection
Volume70
Issue number1
Publication statusPublished - 2007 Jan 1

Fingerprint

titanium dioxide
Daucus carota
Disinfection
disinfection
carrots
Bacillus cereus
bacteria
Salmonella typhimurium
Salmonella Typhimurium
Vegetables
Bacteria
Aerobic Bacteria
antibacterial properties
raw vegetables
Escherichia coli
washing
Foodborne Diseases
liquids
fresh produce
foodborne illness

ASJC Scopus subject areas

  • Food Science
  • Applied Microbiology and Biotechnology
  • Biotechnology

Cite this

Cho, M., Choi, Y., Park, H., Kim, K., Woo, G-J., & Park, J. (2007). Titanium dioxide/UV photocatalytic disinfection in fresh carrots. Journal of Food Protection, 70(1), 97-101.

Titanium dioxide/UV photocatalytic disinfection in fresh carrots. / Cho, Mihee; Choi, Yoonjung; Park, Hyojin; Kim, Kwansik; Woo, Gun-Jo; Park, Jiyong.

In: Journal of Food Protection, Vol. 70, No. 1, 01.01.2007, p. 97-101.

Research output: Contribution to journalArticle

Cho, M, Choi, Y, Park, H, Kim, K, Woo, G-J & Park, J 2007, 'Titanium dioxide/UV photocatalytic disinfection in fresh carrots', Journal of Food Protection, vol. 70, no. 1, pp. 97-101.
Cho M, Choi Y, Park H, Kim K, Woo G-J, Park J. Titanium dioxide/UV photocatalytic disinfection in fresh carrots. Journal of Food Protection. 2007 Jan 1;70(1):97-101.
Cho, Mihee ; Choi, Yoonjung ; Park, Hyojin ; Kim, Kwansik ; Woo, Gun-Jo ; Park, Jiyong. / Titanium dioxide/UV photocatalytic disinfection in fresh carrots. In: Journal of Food Protection. 2007 ; Vol. 70, No. 1. pp. 97-101.
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