• Journal of Korean Society of Environmental Engineers
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• v.30 no.7
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• pp.743-750
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• 2008

In water treatment plant the Dissolved Ozone Flotation(DOF) System may be employed because this system has various abilities, such that it can remove SS using microbubbles, and it can exert strong oxidation power in removing taste and odor, color, and microbial agents. In order to investigate effectiveness of the DOF system in water treatment, removal characteristics of various water quality parameters were observed depending on the different levels of ozone concentrations. Removal efficiencies of water quality parameters in DOF system were compared with those in DAF(Dissolved Air Flotation) system and in CGS(Conventional Gravity Settling) system. Optimum ozone dose obtained in the pilot experiments was 2.7 mg/L. With increasing ozone dose higher than 2.7 mg/L, removal rates of turbidity, KMnO$_4$ consumption, UV$_{254}$ absorbance, and TOC were reversely lowered. High concentration of ozone dissociate organic matter in water, so that increasing dissolved organic level in effluent. Removal rates of water quality parameters at optimum ozone dose were obtained, such that removal rates of turbidity, KMnO$_4$ consumption, TOC, and UV$_{254}$ asorbance were 88.9%, 62.9%, 47%, and 77.3% respectively. Removal rate of THMFP was 51.6%. For all the parameters listed above, the DOF system was more effective than the DAF system or the CGS system. It is found that the DOF system may be used in advanced water treatment not only because the DOF system is more efficient in removing water quality parameters than the existing systems, but because the DOF system is also required smaller area than the CGS system for the treatment plant.

• Environmental Engineering Research
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• v.21 no.2
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• pp.211-218
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• 2016

Cheonggye-cheon is a partly restored urban stream located in central Seoul. We monitored fecal contamination using three different fecal indicators, total coliforms (TC), fecal coliforms (FC) and E. coli, to assess differences in each indicator on days of varying weather conditions. Presumptive TC, FC and E. coli colonies were identified by their 16S rRNA sequences. The results showed that enumeration of E. coli provided a better reflection of fecal contamination of the stream than TC and FC. The main sources of contamination were the inflow of fecal-polluted groundwater from the vicinity of a subway line and two inflowing streams. The fecal contamination was worsened on days with heavy rain because untreated sewage from a collecting facility flowed into the stream. Moreover, growth potential of fecal indicator (E. coli) in situ induced by algal exudates was measured. Our results suggest that an appropriate standard based on E. coli rather than TC and FC should be established for improving water quality management strategies of Cheonggye-cheon in the future.

• Proceedings of the SCSK Conference
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• 2003.09b
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• pp.524-526
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• 2003

Lipsticks are cosmetics which do not contain water and are usually preserved with parabens. When submitted to the Challenge Test, theses products did not reach the CTFA criteria, which means that microbiological contamination could occur before the end of its shelf life. The aim of this study was to evaluate the contamination level of 130 lipsticks after its use. Microorganisms were isolated from 14,6 % of the samples. However, only in two samples (1,5%) the contamination level exceeded the 100 CFU/g level, which means that, although the preservative system was not efficient to eliminate bacteria, the lack of free water was enough to prevent the microbial development. Total bacteria and fungi were determined by conventional methodology, according to CTFA Microbiological Guidelines. The microbes were then isolated and characterized as normal skin flora microorganisms. This suggest that products were contaminated by the constant application of lipsticks by consumers. This could lead to cross contamination when the same product is shared by several people. Extra care should be taken into account when this type of products are available to be tested by several consumers in demonstration displays.

• Journal of Bio-Environment Control
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• v.28 no.3
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• pp.197-203
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• 2019

This study was carried out to investigate the effect of chlorine water and plasma gas treatment on the quality and microbial control of Latuca indica L. baby Leaf during storage. Latuca indica L. baby leaves were harvested from a plant height of 10cm. They were sterilized with $100{\mu}L{\cdot}L^{-1}$ chlorine water and plasma-gas (1, 3, and 6hours), and packaged with $1,300cc{\cdot}m^{-2}{\cdot}day^{-1}{\cdot}atm^{-1}$ films and then stored at $8{\pm}1^{\circ}C$ and RH $85{\pm}5%$ for 25days. During storage, the fresh weight loss of all treatments were less than 1.0%, and the carbon dioxide and oxygen concentrations in packages were 6-8% and 16-17%, respectively for all treatments in the final storage day. The concentration of ethylene in the packages fluctuated between $1-3{\mu}L{\cdot}L^{-1}$ during the storage and the highest concentration of ethylene was observed at 6 hours plasma treatment in the final storage day. The off-odor of all treatments were almost odorless, the treatments of chlorine water and 1 hour plasma maintained the marketable visual quality until the end of storage. Chlorophyll content and Hue angle value measured at the final storage day were similar to those measured before storage in chlorine water and 1 hour of plasma treatments. E. coli was not detected immediately after sterilization in all sterilization treatments. After 6 hours of plasma treatment, the total bacteria fungus counts were lower than the domestic microbial standard for agricultural product in all sterilization treatments. The total aerobic counts in the end storage day increased compared to before storage, whereas E. coli was not detected in all sterilization treatments. The sterilization effect against bacteria and fungi was the best in chlorine water treatment. Plasma treatment showed sterilization effects, but within a prolonged period of time. In addition, the sterilization effect decreased gradually. These results suggest that chlorine water and plasma treatment were effective in maintaining Latuca indica L. baby Leaf commerciality and controlling microorganisms during postharvest storage.

• Journal of Animal Science and Technology
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• v.50 no.2
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• pp.227-236
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• 2008

The objective of this study was to evaluate the effect of dietary lycopene supplementation on meat quality in Longissimus Muscle of Korean native pigs. Meat samples were obtained from pigs which had been fed with finishing pig diets containing basal diets(C), 200 ppm lycopene (T1), 400 ppm lycopene (T2), and 800 ppm lycopene(T3). Longissimus muslce pH was not influenced by feeding lycopene. Total microbial counts of treatments were significantly lower than those of control at 0 day of storage (p<0.05). Counts of lactic acid bacteria and coliform of T2 and T3 were significantly lower than those of control and T1 at 0 day of storage(p<0.05). Regardless of packaging, microbial counts increased as the storage period increased(p<0.05). While water-holding capacity (WHC) values of the treatments were lower than those of control, cooking losses values of treatments were higher than those of control (p<0.05). Therefore, it can be concluded that Korean native pigs fed lycopene supplemented diets affect the microbial counts and meat quality (volatile basic nitrogen, WHC and cooking loss) compared with conventional ones. These results may show a fundamental data on production of Korean native pork.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.279-287
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• 2007

Quality attributes of fresh-cut chicory (Clchorium intybus L.var. foliosum) treated with hydrocooling and packing type were investigated in terms of weight loss, respiration, vitamin C content, microbial load and sensory properties during storage at $4^{\circ}C\;and\;10^{\circ}C$. Fresh chicory was trimmed and washed 3 times with cold water $(1^{\circ}C,\;5^{\circ}C)$ and tap water $(10^{\circ}C)$ for 30 sec and then packaged in polypropylene (PP) film bag and polyethylene terephthalate (PETE) tray, and stored for 9 days at $4^{\circ}C\;and\;10^{\circ}C$. Weight loss was decreased by washing and packing generally. Respiration rate was increased slowly in the storage at $4^{\circ}C$. Vitamin C content of chicory packaged within PETE tray were decreased gradually during storage at $4^{\circ}C$. Hydrocooling and packing within PETE tray treatments resulted in approximately 1-2 log CFU/g reduction of microbial load.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.2
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• pp.231-238
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• 2008

Quality attributes of fresh-cut sesame leaf (Perilla frutescens var. japonica) as affected by hydrocooling and packing were investigated in terms of weight loss, respiration, vitamin C content, total chlorophyll content, microbial load and sensory properties during storage at 4 and $10^{\circ}C$. Fresh sesame leaf was trimmed and washed with cold water (1, $5^{\circ}C$) as well as tap water ($13^{\circ}C$) for 30 sec 3 times and then packaged in PP (polypropylene) film bag and PETE (polyethylene terephthalate) tray, and stored for 9 days at 4 and $10^{\circ}C$. Weight loss was decreased by washing and packing. Respiration rate was increased slowly over the storage at $4^{\circ}C$. Vitamin C content and total chlorophyll contents of sesame leaf packaged within PETE tray decreased gradually during storage. Hydrocooling and packing within PETE tray treatments resulted in approximately $1{\sim}2\;log\;CFU/g$ reduction of microbial load.

• Food Science and Preservation
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• v.15 no.1
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• pp.1-8
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• 2008

Quality attributes of fresh-cut pak-choi (Brassica campestris var. chinensis) as affected by hydrocooling and packing were investigated in terms of weight loss, respiration, vitamin C content, total chlorophyll content, microbial load and sensory properties during storage at 4 and $10^{\circ}C$. Fresh pak-choi was trimmed and washed with cold water $(1^{\circ}C)$ as well as tap water $(6^{\circ}C)$ for 30 sec 3 times and then packaged in PP (polypropylene) film bag and PETE (polyethylene terephthalate) bay, and stored for 9 days at 4 and $10^{\circ}C$. Weight loss was decreased by washing and packing generally. Respiration rate was increased slowly over the storage at $4^{\circ}C$. Vitamin C content and total chlorophyll contents of pak-choi packaged within PETE bay decreased gradually during storage. Hydrocooling and packing within PETE bay treatments resulted in approximately 1-2 log CFU/g reduction of microbial load.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.171-177
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• 2008

The effects of hydrocooling and packaging type on the quality attributes of fresh-cut crown daisies (Chrysanthemum coronarium var. spatiosum) were investigated by examining weight loss, respiration, vitamin C content, total chlorophyll content, microbial load, and sensory properties during storage at 4 and 10$^{\circ}C$. Fresh crown daisies were trimmed and washed with cold water (1 and 5$^{\circ}C$) as well as tap water (10$^{\circ}C$) 3 times each for 30 sec. They were then packaged in PP (polypropylene) film bags or PETE (polyethylene terephthalate) trays, and stored for 9 days at 4 and 10$^{\circ}C$, respectively. In general, weight loss was reduced as a result of the washing and packaging. The respiration rate increased slowly during storage at 4$^{\circ}C$, and the vitamin C and total chlorophyll contents of the crown daisies packaged in PETE trays decreased gradually during storage. Finally, the treatments consisting of hydrocooling and then packaging in PETE trays resulted in approximately 1-2 log CFU/g reductions in microbial load.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.749-760
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• 2007

The purpose of this study was to evaluate the microbiological quality of non-heat-processed foods and the effects of HACCP implementation. Here, cabbage salad and cucumber&onion salad were selected and we investigated HA(Hazard Analysis) by checking microbiological quality, time and temperature, pH, and water activity at each processing stage. Thus, the receiving of spices and dressings, washing and sterilizing, cutting, cooking, and serving stages were all considered CCPs. Before implementing HACCP, microbial analysis showed that standard plate counts and coliform counts were higher than standard levels in most of the raw ingredients of each menu, as well as during the production process. The microbiological quality of the utensils and employee's hands used during cooking indicated levels requiring direct management. Evaluations of falling bacteria-in the foodservice establishment work areas ranged from $2{\sim}12CFU/plate$. However, after HACCP implementation, microbiological levels improved to standard levels fly sanitation education. Also, the number of falling bacteria were lower than before implementing HACCP. Therefore, it is essential the foodservice operations make efforts to implement HACCP, so that microbiological hazard levels are lowered and hygienic status improved.