Submitted to: International Journal of Food Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/2018
Publication Date: 4/23/2018
Citation: Kingsley, D.H., Perez, R., Niemira, B.A., Fan, X. 2018. Evaluation of gaseous chlorine dioxide for the inactivation of tulane virus on blueberries. International Journal of Food Microbiology. 273:23-32.
Interpretive Summary: Berry fruits are prone to contamination with pathogenic human viruses due to irrigation with non-potable water sources, and in some cases non-hygienic manual picking. These viruses are very difficult to inactivate. Here we show that gaseous chlorine dioxide can inactivate a human norovirus surrogate on the surface of blueberries. Once evaluated in larger scale for its efficacy and for product quality attributes, this dry non-thermal intervention technology should be widely accepted by industry.
Technical Abstract: To determine the effectiveness of gaseous chlorine dioxide against a human norovirus surrogate on produce, chlorine dioxide was generated and applied to Tulane virus coated blueberries in a 240 ml treatment chamber. Chlorine dioxide was produced by acidifying sodium chlorite solution. Initial assessments indicated that blueberries treated with chlorine dioxide generated from 1 mg or less acidified sodium chlorite in the small chamber appeared unaffected, while 10 mg or more of acidified sodium chlorite altered the appearance and quality of the blueberries. Treatments of inoculated blueberries with chlorine dioxide generated from 0.1 mg sodium chlorite reduced the virus populations by more than 1 log after exposure for 30 to 330 min. For the 1 mg sodium chlorite treatments, the virus populations were reduced by more than 2.2 log after 15 min exposure and to non-detectable levels ( more than 3.3 logs reductions) after 180 min exposure. Measured concentrations of chlorine dioxide peaked in the treatment chamber at 0.9 micrograms/l after 10 min for 0.1 mg treatments and 600 micrograms/l around 20 min for 1 mg treatment. Overall results indicate that chlorine dioxide could be a feasible waterless intervention for blueberries and other produce.