Antimicrobial Effects of Chlorine Dioxide Gas on Pathogenic Escherichia coli and Salmonella spp. Colonizing on Strawberries for Export

January 05, 2023

수출 딸기 중 이산화염소 가스 처리를 통한 병원성 Escherichia coli와 Salmonella spp. 저감화 효과

이효섭1 ·심원보2 ·안현미3 ·하지형4 ·이은선3 ·김원일3 ·김황용5 ·김세리3 * 1 국립농업과학원 농산물안전성부 화학물질안전과, 2경상대학교 식품공학과 3국립농업과학원 농산물안전성부 유해생물팀, 4세계김치연구소 위생안전성분석센터 5농촌진흥청 기술협력국 국외농업기술과

ABSTRACT - The purpose of this study was to determine the antimicrobial effects of ClO2 gas on pathogenic E.coli and Salmonella spp. colonizing on the fruit surface of strawberries for export. Factorial design was employed to treat strawberries inoculated with pathogenic E. coli or Salmonella spp. with a combination of ClO2 gas concentrations (10, 20, 30, 40, and 50 ppmv), RH (50, 70, and 90%), and treatment time (0, 5, 10, 20, and 30 min). Interaction between the factors was observed to note that the reduced levels of microbial population were the highest when RH is set at 90% with gas concentration- and treatment time-dependent manner. With RH and gas concentration fixed at 90% and 50 ppmv, the populations of E. coli and Salmonella spp. decreased by 2.07 and 2.28 log CFU/g when treated for 20 min whereas population reduction by 0.5 and 0.7 log CFU/g were observed when treated for 5 min, respectively. The results help establish most effective conditions for ClO2 gas treatment to enhance microbial safety of strawberries for export.

본 연구는 수출 딸기 중 병원성 E. coli와 Salmonella spp.를 제어하기 위하여 이산화염소 가스 농도, 상대습도, 시간에 따른 이산화염소 가스의 미생물 저감효과를 조사하였다. 병원성 E. coli, salmonella spp.를 접종한 딸기에 이산화염소 가스 농도(10, 20, 30, 40, 50 ppmv), 상대습도 (50, 70, 90%), 처리시간(0, 5, 10, 20, 30분)에 대한 삼요인 실험을 하였다. 그 결과, 각 처리 조건 간의 상호작용이 나타났으며 미생물 저감효과는 상대습도가 가장 높은 조건인 90%에서 이산화염소 가스 농도와 처리시간의 값이 증가할수록 높아지는 경향이 있었다. 상대습도 90%, 이산화염소 가스 농도 50 ppmv에서 처리시간에 따른 미생물 저감화 효과는 5분 동안 처리하였을 때 병원성 E.coli와 Salmonella spp.이 각각 0.5, 0.7 log CFU/g 정도 감소하였으나 20분간 처리하였을 때는 각각 2.07과 2.28 logCFU/g 정도 감소하였다. 따라서 본 연구는 수출 딸기 중 병원성 E. coli와 Salmonella spp.를 제어하기 위한 최적의 이산화염소가스 처리 조건을 확립한 결과로서 수출 딸기의 미생물 안전성 향상에 기여할 수 있으리라 사료된다.

In this study, the microbial reduction effect of chlorine dioxide gas according to chlorine dioxide gas concentration, relative humidity, and time was investigated to control pathogenic E. coli and Salmonella spp. in exported strawberries. Chlorine dioxide gas concentration (10, 20, 30, 40, 50 ppmv), relative humidity (50, 70, 90%), treatment time (0, 5, 10, 20 and 30 minutes), a three-factor experiment was performed. As a result, the interaction between each treatment condition was revealed, and the microbial reduction effect tended to increase as the chlorine dioxide gas concentration and treatment time values increased under the condition of the highest relative humidity of 90%. 90% relative humidity,

As for the microbial reduction effect according to the treatment time at a chlorine dioxide gas concentration of 50 ppmv, pathogenic E.coli and Salmonella spp. decreased by 0.5 and 0.7 log CFU/g, respectively, when treated for 5 minutes, but 2.07 and 2.28 when treated for 20 minutes, respectively. It decreased by about logCFU/g. Therefore, this study was conducted among exported strawberries.

As a result of establishing optimal chlorine dioxide gas treatment conditions to control pathogenic E. coli and Salmonella spp., it is thought that it can contribute to improving the microbial safety of exported strawberries.