Recently, improvement of eggshell hygiene has emerged as an important issue in food industry. Various studies have continued to examine methods for controlling egg-borne pathogen, and among such methods, for table eggs, washing (with UV irradiation) is the most commonly used method. However, this method was not sufficient to control egg microbial contamination. Therefore, the purpose of this study was to verify whether it is appropriate to use ClO2 gas, which has been proven safe in this experiment model, as an alternative to the conventional washing (with UV irradiation) method. As a result, we have identified a range of optimal effectiveness in response to exposure concentrations and time of ClO2 gas. Through experimental models that reflect differences in farm size, a microbial reduction effect of approximately >2 log CFU/eggshell was achieved at 40ppm/8h for small farms, and 160ppm/30min for large farms, indicating greater effectiveness than the conventional method. However, in large-scale experiment, when bulk eggs were stacked and exposed to ClO2 gas, eggs in the depths showed a lower effect by approximately 0.8~1.5 log CFU/eggshell, as compared to the eggs in the upper section. For further study, if technical improvements are achieved in the future studies allowing the gas to better penetrate the depths of stacked eggs, it will be a model that can be more useful to the field.

다양한 식재료의 소독재로 사용되는 이산화염소(ClO2)는 이 물질이 갖는 높은 산화력에 기인된다. 이산화염소가 해충에 대한 방제 가능성이 제기되었고, 이에 대한 실증 시험은 이 물질의 살충기작을 증명하여 주었다. 그러나 이 물질의 살충 기작은 밝혀지지 않았다. 본 연구는 이산화염소의 훈증처리에 따라 곤충 체내에서 일어나는 산화적 스트레스를 항산화효소의 발현 유발에 따라 가능성을 찾았다. 다시 이산화염소를 처리하고 세포내에 존재하는 활성산소(reactive oxygen species: ROS)를 정량화한 결과 ROS의 급격한 증가를 관찰하였다. Vitamin E와 같은 항산화제를 이산화염소와 처리할 경우 살충력은 크게 낮아져 산화적 스트레스에 기인된 살충기작을 뒷받침하여 주었다. 이러한 ROS 유발은 다양한 생리현상을 일으키는 분자를 교란하여 곤충의 신경, 면역, 행동 및 발육 생리를 저해는 것으로 나타났다. 이러한 결과는 산화적 스트레스에 의해 살충효과를 일으키는 새로운 해충 방제제의 개발을 제시하고 있다.

Chlorine dioxide gas is a relatively new sanitizer in the food industry and has more accessibility than its aqueous form. Depending on the generation method of ClO2, there can be byproducts like chlorite and chlorate ions that can decrease the disinfectant efficacy and purity of ClO2. Recently, a new technology has been developed that generates chlorine dioxide without using chlorine gas. This new electrochemical method generates gaseous chlorine dioxide from aqueous sodium chlorite (NaClO2). Unlike earlier methods, there is reduced generation of byproducts, including chlorite and chlorate. Additionally, the purity of ClO2 obtained by this method can be as high as 98%. The aim of this study was to evaluate the effect of ClO2 gas, generated by the electrochemical method, against the foodborne microorganisms occurring on slaughter equipment and livestock carcasses. Using AISI 304 stainless steel in livestock processing equipment, the disinfectant effect of chlorine dioxide gas, in presence of organic matter such as yeast extract and feces, on E. coli and S. typhimurium contamination, was examined. Both E. coli and S. typhimurium counts were reduced by more than 5 log cycles in presence of 2.5% and 5% feces. When beef, pork skin, and chicken wings were treated with chlorine dioxide gas, despite significant differences in comparison with the control group, the microbial count was reduced by less than 2 log cycles. Overall, our results confirmed the applicability of gaseous chlorine dioxide as a disinfectant in livestock processing equipment and livestock products.

이산화염소(ClO2)는 높은 산화력으로 여러 미생물의 소독제로 널리 사용되어 왔다. 최근 훈증처리가 가능한 제형으로 개발되면서 이산화염소의 해충 방제 적용 가능성이 제기되었고, 실제로 의학 및 저곡해충에 대한 살충력이 입증되었다. 그러나 기존의 살충제와 다른 형태의 화학 구조를 지닌 이산화염소에 대한 살충기작은 알려진 바가 없었다. 이산화염소에 대한 노출은 곤충으로 하여금 산화적 스트레스를 유발하였다. 이는 항산화효소의 발현이 증가로 이어졌으며, 여기에 항산화제를 처리할 경우 이산화염소의 살충력을 크게 둔감시켰다. 실제로 이산화염소에 노출된 곤충은 체내 활성산소량이 크게 증가하였다. 후속 연구는 곤충 체내로 들어간 이산화염소가 활성산소를 증가시키고 다양한 분자종말점을 변형시켜 신경, 면역, 행동 및 발육 생리를 교란한다는 살충기작 모델을 제시하게 되었다.

Chlorine dioxide gas is a relatively new sanitizer in the food industry that has more accessibility than its aqueous form. Depending on the method by which ClO2 gas is generated, there can be byproducts like chlorite and chlorate ions, which can decrease its disinfectant effect and purity. Recently, new technology that generates chlorine dioxide without using chlorine gas has been developed to remove those defects. This new electrochemical method generates gaseous chlorine dioxide from aqueous sodium chlorite (NaClO2). The present study was conducted to evaluate the effects of ClO2 gas generated by an electrochemical method against foodborne microorganisms. To accomplish this, ClO2 gas at different concentrations (1, 5, 10 and 20 ppm) was applied to E. coli and S. Typhimurium for different exposure times (1, 5, 10, 15 and 20 min) under room temperature conditions at <40% relative humidity. The results revealed ClO2 gas was highly effective for the inactivation of E. coli and S. Typhimurium and showed a reduction in populations of over 5 log CFU/ml under ambient conditions with low relative humidity (30–40%). In conclusion, ClO2 gas treatment is highly applicable to control of foodborne pathogens.

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 log CFU/g 정도 감소하였다. 따라서 본 연구는 수출 딸기 중병원성 E. coli와 Salmonella spp.를 제어하기 위한 최적의 이산화염소가스 처리 조건을 확립한 결과로서 수출 딸기의 미생물 안전성 향상에 기여할 수 있으리라 사료된다.

This study was conducted to investigate the effect of chlorine dioxide fumigation as a substitute for sulfur fumigation which has been used as a method to prevent the quality change of persimmon during storage and distribution process. Dried persimmons were treated with chlorine dioxide gas concentration (0, 15 30, and 45 ppm) and time (0, 15, 30, and 45 min) and microbiological changes, texture properties and color of the treated samples were investigated during storage at room temperature. Total aerobic bacteria, yeast and mold numbers after chlorine dioxide gas fumigation were decreased when compared with the control group. The inhibitory effects of total aerobic bacteria, yeast, and mold were observed during storage. The texture properties and color value of dried persimmons were not affected by chlorine dioxide gas fumigation concentration and time. There was no difference in quality between chlorine dioxide gas fumigation treatment group and control group. These results suggested that chlorine dioxide gas fumigation treatment can be utilized as a processing technique to secure microbiological storage stability of dried persimmons.

농산물의 미생물학적 안전성에 대한 요구가 증대되면서 미생물에 의한 농산물의 오염 및 균의 발생을 최소화하기 위해 이산화염소() 가스를 이용한 포도저장 실험을 수행하였다. 실험 결과 중량감소율은 상온, 저온저장 모두 20 ppm+Ny/PE/L-LDPE 처리구가 가장 적었고 가용성 고형물 함량은 상온, 저온저장 모두 무처리구가 다른 포장구에 비해 높은 값을 나타내었으며 20 ppm+Ny/PE/L-LDPE 처리구는 감소했다. 적정산도 값은 상온, 저온