• 한국식품영양학회지
• /
• 제21권4호
• /
• pp.499-509
• /
• 2008

The purpose of this study was to investigate the changes in physicochemical and sensory properties of raw fruits during washing and chlorine treatments. Strawberry and banana were pre-prepared at different concentration of chlorinated water(0 ppm, 50 ppm and 100 ppm), immersion time(3 min and 5 min), and number of post-rinsing(1 time, 2 times and 3 times). The physicochemical properties such as pH, sugar contents, residual chlorine contents, color values and hardness of the fruits were analyzed, and the sensory quality were evaluated throughout the sterilization treatment process. After washing strawberry with 100 ppm chlorinated water and 3 times of post-rinsing, pH and residual chlorine contents were showed a little difference, while sugar contents, hardness, and color values(L, a and b) were reduced. In case of banana, pH, sugar contents and residual chlorine contents were not affected, and hardness and L color value were reduced. However, a and b color values of banana were gradually increased as the development of brown discoloration. Sensory properties of the samples were affected by the chlorine sterilization treatment. In overall acceptance, strawberry and banana treated with 100 ppm chlorinated water showed the lowest scores among treatments. Therefore it could be suggested that the application of 50 ppm chlorinated water for $3{\sim}5$ minutes with over 3 times of post-rinsing was the effective pre-preparation method without affecting the quality of the fruits.

• 한국식품영양학회지
• /
• 제21권2호
• /
• pp.176-183
• /
• 2008

This study examined the anti-microbiological effects of chlorine treatment on the surface of fresh fruits, in order to improve microbiological safety in school foodservice operations. Non-peeled fruit(strawberries) and peeled fruit(bananas) were treated with different concentrations of chlorinated water and rinsing numbers, followed by microbiological testing. The fruits were immersed at different concentrations of chlorinated water(0 ppm, 50 ppm, and 100 ppm) and durations(3 min and 5 min), and were then rinsed with tap water(one time, two times, or three times). The total viable cell counts of both the strawberries and bananas ranged from $10^3$ CFU/g to $10^4$ CFU/g, and coliform levels ranged from $10^2$ CFU/g to $10^3$ CFU/g. As the chlorine concentration, immersion time, and rinsing number increased, anti-microbiological activity increased. The largest microbial reduction was shown with immersion for 5 min in 100 ppm chlorinated water and three rinsings. In the strawberries, this treatment reduced the initial population of total viable cells and coliforms by 3.29 log CFU/g and to an undetectable level, respectively, no total viable cells or coliforms were detected on the banana surface following this treatment. However, after a sterilization treatment with immersion for 5 min in 50 ppm chlorinated water and three rinsings, the total viable cell counts and coliform counts of the strawberries and bananas decreased to acceptable levels, based on the microbiological standards for ready-to-eat foods. Overall, it was shown that the sterilization treatment of 50 ppm chlorinated water, soaking for 5 min, and three rinsings provided an effective reduction in surface microbes, and enhanced the microbiological safety of the fruit.

• 한국식품조리과학회지
• /
• 제20권6호
• /
• pp.589-597
• /
• 2004

This study was conducted to investigate the effects of various kinds of electrolyzed and chlorinated waters on the sensory and microbiological qualities of fresh-cut lettuce and to determine the most suitable electrolyzed water for the vegetable dishes, without heat treatment, at institutional foodservices. The sensory evaluation resulted in higher scores on the 1st-day of storage for the EW-1 (diaphragm type 1) and EW-3 (non-diaphragm type) compared to that for EW-2 (diaphragm type 2), with regard to their appearance, discoloration, texture, taste and overall acceptability characteristics. However, over time, EW-3 ranked highest, with a score of 8.00 (very like), on the 4th-day of storage, which maintained the highest level up to the 7th-day of storage, at which time the score was 7.00 (fairly like). The CW (chlorinated Water) had a significantly lower score, due to the smell of chlorine, although there was no concern with relation to chlorine residue from the electrolyzed waters. Microbial examinations of the total plate count revealed that immersing lettuce into EW-3 brought about l/3,000 to 1/30,000 reductions in the microbial counts of the TW treatment or untreated samples for up to seven days of storage. The CW treatment gave a 1/10 reduction in the microbial counts compared with the TW (tap water) treatment. The coliform bacterial counts also showed similar trends to those of the total plate count values. With regards to the psychotropic bacterial count, EW-3 was able to result in as much as a 1/30,000 reduction in the initial counts. As vegetable dishes, such as salad, can not be heat-sterilized, the utilization of EW-3 for the preparation of vegetable dishes without heat treatment will be an excellent choice to improve the critical control point in production state as a new effective means for sanitizing management.

• 한국식품과학회지
• /
• 제38권1호
• /
• pp.28-34
• /
• 2006

연구에서는 세정 및 표면살균처리 시스템을 개발 제작에 의한 세정, 표면살균처리 및 저장효과를 살펴보기 위해 치커리를 시료 로 수확후 저장기간별 품질평가를 실시하였다. 표면살균처리를 위해 오존수와 염소수를 사용한 결과 3 ppm 오존수와 염소수 100 ppm의 표면살균 처리는 미생물적 결과에서 커다란 차이를 보이지 않았으나, 두 살균수 모두 식품가공에 있어 제균력을 가지고 있음을 확인 할 수 있었다. 처리 조건을 신선편이 치커리에 적용해본 결과 저장 조건에 있어서는 $4^{\circ}C$에서 시료들은 관능적 평가에 있어서 9일까지는 양호한 상태를 보였으나, 이화학적 특성인 총비타민C와 총클로로필 함량을 시험해보았을 때, 영양소적 손실을 보였고, $10^{\circ}C$에 저장한 치커리의 경우 6일 이후 급격히 상품가치를 잃었다. 본 연구 결과를 토대로 위생적이고 안전한 최 소가공 농산물의 생산을 위하여 기계세정을 이용한 공정시간의 단축과 살균과정을 이용하여 식품 안전성의 위험이 될 수 있는 미생물의 오염을 막을 수 있고, 오존수를 이용하여 염소수 소독에 의존하고 있는 일반적인 생산과정의 중점관리로 지적되었던 사항을 개선할 수 있는 새로운 위생관리 방안으로써 이용 가치 있다고 평가된다.

• 분석과학
• /
• 제30권2호
• /
• pp.57-67
• /
• 2017

This study was conducted to develop an analytical technique for determination of chlorite and chlorate concentrations in fresh-cut food and dried fish products by an ion chromatography/conductivity detection method using a hydroxide mobile phase. Deionized water was added to homogenized samples, which were then extracted by ultrasound extraction and centrifuged at high speed (8,500 rpm). Subsequently, a Sep-Pak tC18 cartridge was used to purify the supernatant. Chlorite and chlorate ions were separated using 20 mM KOH solution as the mobile phase and Dionex IonPac AS27 column as the stationary phase. Ethylenediamine was used as sample preservative and dibromoacetate was added to adjust for the disparity in extraction efficiencies between the food samples. The method detection limit) for chlorite and chlorate were estimated to be 0.2 mg/kg and 0.1 mg/kg, respectively, and the coefficient of determination ($r^2$) that denotes the linearity of their calibration curves were correspondingly measured to be 0.9973 and 0.9987. The recovery rate for each ion was 92.1 % and 96.3 %, with relative standard deviations of 7.47 % and 6.18 %, respectively. Although neither chlorite nor chlorate was detected in the food samples, the analytical technique developed in this study may potentially be used in the analysis of disinfected food products.

• 한국식품과학회지
• /
• 제41권4호
• /
• pp.452-457
• /
• 2009

친환경 기능성 채소로서 시장수요가 증가하고 있는 고품질 새싹채소의 수확 후 미생물 안전관리와 품질유지 유통기술을 개발하고자 메밀 새싹의 내재미생물을 검지하고 살균소독제로서 차아염소산나트륨의 적용 농도별 미생물 억제효과를 살펴보았다. 그 결과, 메밀 새싹의 주요 내재미생물 균총은 Enterobacter, Sphingomonas, Klebsiella 등이 대부분으로 $10^5-10^7$ CFU/g 수준이었으며, 그 종류는 종자 자체의 내재미생물과 유사하였고, E. coli O157:H7, Sal. Typhimurium, L. monocytogenes 등의 병원균은 검출되지 않았다. 50-150 ppm의 차아염소산염 용액으로 처리한 메밀 새싹의 생균수는 무처리구에 비해 약 1 log cycle 이상 감소하였으나 적용농도에 따른 차이는 유의적이지 않았다. 저온저장 7일 후 관능평가에서 100 ppm 이상의 염소수처리 새싹이 상대적으로 우수하게 평가되어 적정 농도의 염소수처리가 메밀 새싹채소의 미생물 억제 및 외관품질 유지에 긍정적인 효과를 나타내는 것으로 확인되었다.

• 한국환경성돌연변이발암원학회지
• /
• 제21권2호
• /
• pp.113-117
• /
• 2001

The screening of various molecular descriptors for predicting carcinogenic, mutagenic and teratogenic activities of chlorinated aliphatic compounds as drinking water disinfection byproducts (DBPs) has been investigated for the application of quantitative structure-activity relationships (QSAR). The present work embodies the study of relationship between molecular descriptors and toxicity parameters of the genotoxicity endpoints for the screening of relevant molecular descriptors. The toxicity Indices for 29 compounds constituting the testing set were computed by the PASS program and active values were chosen. We investigate feasibility of screening descriptors and of their applications among different genotoxic endpoints. The correlation to teratogenicity of all 29 compounds was significantly improved when the same analysis was done with 20 alkanes only without alkene compounds. The HOMO (highest occupied molecular orbital) energy and number of Cl parameters were dominantly contributed.

• Applied Biological Chemistry
• /
• 제30권1호
• /
• pp.40-45
• /
• 1987

Alcaligenes aquamarinus에 의한 각종 PCBs와 유기염소계 농약 및 토양중의 PBC-42 분해 등을 검토하고 TLC 등으로 분해산물을 검정한 결과 PCBs에서는 염소화도가 낮은 PCBs가 더 쉽게 분해되었고 유기염소계 농약에서는 p,p'-DDT>r-BHC>Thiolix 순으로 분해되었다. 토양중의 PCB-42의 분해는 살균하지 않은 토양시료에서 $25^{\circ}C$, 25일 배양으로 약 40%가 분해되었다. PCB-42의 분해로 생성된 황색물질의 최대 흡수파장은 pH 4.5에서 258nm와 295nm이었고 분해산물의 일종인 p-chlorobenzoic acid가 TLC와 GC에 의하여 확인되었다.

• 한국식품위생안전성학회지
• /
• 제31권4호
• /
• pp.258-263
• /
• 2016

본 연구는 식품접객업소 등에서 사용되는 94건의 물수건(위생처리업소 39건, 식품접객업소 55건)에 대하여 위생지표세균, 중금속, 염소부산물 등에 대한 안전성을 조사하였다. 중금속 안전성 조사결과 납은 불검출 ~ 0.41 mg/kg(불검출 75건), 비소는 불검출 ~ 0.25 mg/kg(불검출 93건), 카드뮴은 불검출 ~ 0.01 mg/kg(정량한계 미만 7건, 불검출 87건), 수은은 0.003 mg/kg ~ 0.09 mg/kg, 6가크롬은 모든 시료에서 검출되지 않았다. 이 중 납의 검출량이 가장 많았으나, 가장 높은 검출량인 0.41 mg/kg조차 납 규격기준(20 mg/kg 이하)의 2.1%로 매우 낮은 수준이었다. 미생물 안전성의 경우 대장균은 모든 시료에서 음성이었으며, 일반세균수는 43건 양성이고, 그 중 24건은 규격기준을 초과하였다. 물수건의 포장상태는 세균의 오염 및 물수건 간의 교차오염에 큰 영향을 끼치는 것으로 확인할 수 있었다. 포장에 따른 미생물 오염 비교결과는 덕용포장이고 개봉포장일 때 세균의 오염이 가장 높았다. 수거 시 위생물 수건의 수분함량과 미생물의 상관관계를 확인해본 결과 유의성은 없었으며, 각 시료별 수분함량은 50.0% ~ 77.0% (평균 61.9%)이었다. 물수건 소독에 사용되는 염소화합물로부터 유래되는 염소부산물(클로라이트, 클로레이트)은 88건 중 17건(19.3%)에서 검출되었다. 본 연구결과는 물수건의 제조업 및 식품접객업 종사자의 교육 및 안전관리정책의 기초자료로 활용할 수 있을 것으로 생각된다.

• 한국습지학회지
• /
• 제9권1호
• /
• pp.107-114
• /
• 2007

This study aimed to investigate the hexachlorobenzene (HCB) dechlorinating ability of sediment microbes collected from a natural canal receiving secondary effluents from an industrial estate and nearby factories. Nine sites along the stream and one in the estuary in the Gulf of Thailand into which the canal spills were specified and sampling for sediment and water. Preliminary analysis of the sediments showed that the first four sites nearest to the discharging location were contaminated by HCB within the range of 0.18 to 1.25 ppm. Apart from that, 1,3,5-trichlorobenzene which has never been commercially produced or used in any manufacturing processes except for the transformation from higher chlorinated benzene was also identified in the range of 0.16 to 0.24 ppm. This suggested a possibility of sporadically HCB contamination in this stream. Of more important, people in the community along this canal earn their living by coastal fishery; hence, posing a risk of spreading HCB and its less chlorinated congeners via food chain from caught marine creatures to human. As a result, there is an urgent need to understand the behavior of HCB dechlorination in this stream sediment which can lead to a clean-up action in the future. Serum bottles with sediment slurries (sediment to water ratio of 1:1 (v/v) and filtered to remove particles larger than 0.7 mm) from each site were inoculated with 2 mg/l of HCB, kept anaerobically in the dark at room temperature without any nourishment, and analyzed for HCB and its less-chlorinated congeners every 6 days. Total chemical oxygen demand, suspended solids, and volatile suspended solids were in the range of 21,492-73,584, 158,100-518,100 and 6,000-32,700 mg/l, respectively. It was found that all sediment slurries began to dechlorinate HCB in 12 to 30 days and the HCB was completely removed within 42 to 60 days or so. On the other hand, there was no HCB dechlorination occurred in the controlled set which was sterilized by autoclaving prior to the addition of HCB. This implies that the HCB transformation was solely due to microorganisms' activities. HCB was dechlorinated principally via pentachlolobenzene to 1,2,3,5-tetrachlorobenzene and terminated at 1,3,5-trichlorobenzene which is the major pathway as reported by many researchers. Dichlorobenzene has not been detected in any samples within the dechlorination period of 60 days. The results indicate that the microbial matrix in the sediment of this stream has an outstanding capability to dechlorinate HCB. Existing substrates and nutrients which mainly sorbed onto the solid phase and the typical temperature in Thailand were sufficient and suitable to promote the activities of these HCB-dechlorinating microbes.