• Animal Bioscience
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• 제36권5호
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• pp.797-809
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• 2023

Objective: Many scientists have investigated solutions to reduce microbiological risks in dry-aged meat after the dry-aging technology was revived for high quality and value-added premium meat product in the market. This study aimed to investigate the effect of scoria powder in onggi (Korean earthenware) on the meat quality of pork loins during 21 days of dry aging and to elucidate its mechanism of action. Methods: The pork loins were randomly divided into three groups: aged in vacuum-packaging, onggi containing red clay only (OR), and onggi containing 30% red clay and 70% scoria powder (OS). Microbial analyses (total plate count and Lactobacillus spp.) and physicochemical analyses (pH, shear force, volatile basic nitrogen [VBN], water activity, 2-thiobarbituric acid reactive substances, water content, water holding capacity, cooking loss, and color analysis) of aged meat were conducted. Far-infrared ray emission, quantification of immobilized L. sakei and microstructure of onggi were investigated to understand the mechanism. Results: On day 21, the meat aged in OS exhibited lower pH, shear force, VBN, and water activity than those aged in OR, along with an increase in the number of Lactobacillus spp. OS had a smaller pore diameter than OR, implying lower gas permeability, which could promote the growth of L. sakei. Conclusion: OS improved the microbiological safety and storage stability of pork loin during dry aging by increasing number of Lactobacillus spp. possibly due to low permeability of OS.

• 한국식품영양과학회지
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• 제28권1호
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• pp.40-46
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• 1999

Microbiological quality of commercial white ginseng was examined, together with investigation on its water absorption pattern and radiosensitivity of molds isolated from the samples. Comparative effects of phosphine fumigation and gamma irradiation on microbial control and disinfestation of the samples packed in a commercial laminated film and stored for six months at ambient(20oC, 70% RH) and accelerated(40oC, 90% RH) conditions were studied. Commercial white ginseng was contaminated with coliforms by 103~104CFU/g and molds by 102~104CFU/g and thus decontamination process was required for hygienic quality and storage stability. Phosphine fumigation showed no sterilizing effects on microbes contaminated, while gamma irradiation at around 5kGy was effective for decontaminating microorganisms, showing D10 values of 0.48~0.60kGy for isolated molds. Even though the storage insects, Plodia interpuctella Hubner and Lasioderma serricorne(cigarette beetle) were easily destroyed by phosphine fumigation, gamma irradiation less than 5kGy was found effective for both purposes to improve biological quality of stored white ginseng, thereby extending the storage life of packed samples resulting from increased critical moisture content by about 1%(Aw 0.76).

• 동아시아식생활학회지
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• 제14권3호
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• pp.265-274
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• 2004

To investigate the effect of cereal powders on the quality and storage characteristics of sausage, Aw, pH, microbial count, TBA value, VBN value, textual and sensory characteristics were examined. Water activity tended to decrease as storage time prolonged and all the samples showed higher Aw's than that of the control. During the storage period, pH values of all the samples decreased. L, a and b values had a tendency to decrease during the storage period. During the four weeks storage at 4$^{\circ}C$, TBA and VBN values of all the sample showed increasing tendency and were lower than those of the control. Total plate counts of bacteria, the number of lactic acid bacteria and coliform bacteria counts increased as the storage time prolonged. Texture characteristics of all samples increased up to 1 week storage and decreased subsequently. The sensory scores of all the samples decreased as the storage time prolonged.

• 대한영양사협회학술지
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• 제10권4호
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• pp.381-389
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• 2004

The purpose of this study was to investigate effectiveness of sanitization on raw vegetables not heated in foodservice operations. Microbiological examinations of food materials and cooked food with leek Gukgalli were performed in 2 HACCP-implemented foodservices (A and B) appointed by Food and Drug Administrations, and in 2 other foodservices (C and D) not implemented HACCP. 'Washing and sanitizing raw vegetables' were monitored as CCP at A and B foodservices but only washing has been done in pre-preparation at C and D foodservices. Aerobic plate counts of received leek in A and B foodservices were above $10^7$ CFU/g indicating very poor microbiological quality. After sanitization treatment (soaking for 5 minutes in chlorine water: chlorine density 50〜100 ppm), its aerobic plate counts decreased to 7.06×$10^5$ CFU/g (A foodservice) and 4.31×$10^5$ CFU/g (B foodservice), coliform and faecal coliform were not detected. With this result, the effect of microbial reduction by sanitizer was conformed. But, the conditions of leek were still not acceptable by microbiological standards for ready-to-eat foods. After three more times of rinse has been done, the microbial conditions of leek became acceptable. In C and D foodservices, aerobic plate counts of leek showed decreasing trends by 2〜4 times of washings but microbiological quality of leek after pre-preparation were unacceptable by microbiological standards for ready-to-eat foods (C foodservice: 3.58×$10^5$ CFU/g, D foodservice: 1.29×$10^9$ CFU/g). For the prevention of foodborne illness, sanitizing raw vegetables should be performed during pre-preparation of non-heated foods.

• 환경생물
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• 제20권3호
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• pp.189-196
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• 2002

The direct detection of intestinal pathogens and viruses often requires costly, tedious, and time-consuming procedures. These requirements developed a test to show that the water was contaminated with sewage-borne pathogens by assessing the hygienic quality of water based on indicator microorganisms whose presence indicates that pathogenic microorganisms may also be present. Various groups of microorganisms have been suggested and used as indicator microorganisms. Proposed and commonly used microbial indicators are total coliforms, fecal coliforms, fecal streptococci, Clostridium perfringens, heterotrophic plate count, bacteriophage, and so on. Unfortunately, most, if not all, of these indicators are not ideal because of the sensitivity and resistance to environment stresses and disinfection. However, the development of gene probes and PCR technology may give hope for the discovery of rapid and simple methods toy detecting small number of fecal pathogens in various environments.

• Food Science and Biotechnology
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• 제16권3호
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• pp.329-336
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• 2007

Caking has been a serious problem in food, feed, pharmaceutical, and related industries, where dry powdered materials are produced and/or utilized. Caking of dry food powders occurs when water is redistributed or absorbed by the powders during processing and storage. The powders become sticky when their surfaces are mobilized by water, resulting in inter-particle binding, formation of clusters, and inter-particle fusion, which lead to caking. As a result of caking, the solubility of the powdered materials may decrease, lipid oxidation and enzymatic activity may increase, and sensory qualities such as flavor and crispness may deteriorate. Caking may also lead to microbial growth. For consumers, caking of powder products is a sign of poor quality and possible food safety problems. This paper provides a review of factors affecting caking, caking mechanisms, and analysis of caking based on previous studies.

• Advances in environmental research
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• 제12권1호
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• pp.1-15
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• 2023

Wastewater of anthropogenic origin is known to harbor various bacteria that are known to be of potential risk to human health and environment. It is of utmost importance to monitor such water sources. Coliforms present in the sewage water samples of municipal sewage treatment plants located at three different places in the South Gujarat region (Surat, Navsari and Vapi) of India were analyzed for their coliforms load as well as tested for their drug resistance. Using cultivation-based techniques microbial load and drug resistance (Amoxicillin, Tetracycline, Ciprofloxacin, Erythromycin, Trimethoprim and Sulphamethoxazole) were analyzed. Water treatment statistically significantly decreased the bacterial load in Vapi and Navsari samples. The optical density of with and without antibiotics of all the three locations was shown to increase significantly after 72 hours. Of all the isolates tested, except isolate 'VA5' (resisted up to 90 ㎍ of Ampicillin) all other isolates resisted 256 ㎍ concentration of antibiotics tested. This study indicates that the sewage water is being contaminated with drugs and/or antibiotics due to industrial and/or anthropogenic activities. Regular monitoring of the water quality is required followed by implementation of environmental laws for reducing the pollutants, that are of human health and environment concern.

• 한국수산과학회지
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• 제48권5호
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• pp.688-695
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• 2015

The objective of this study was to investigate the effects of bio-floc system that is composed of effective microorganisms (EM) on the microbial composition and water qualities in rearing water and the growth of Chinese white shrimp, Fenneropenaeus chinensis. To investigate the microbial composition according to the bio-floc levels, the study was conducted at 100 and 150% of bio-floc after 5 and 10 days in bio-floc system. The results showed that total bacteria count (TBC) and the counts of Latobacillus sp., Bacillus sp. and Rhodobactor sp., were significantly decreased after 5 days in bio-floc system. To assess the growth of F. chinensis according to the concentrations of bio-floc, the study was conducted at the bio-floc concentrations; 0 (control), 60, 80, 100, 120 and 140% of the prepared bio-floc for 90 days. The growth factors such as daily length and weight gain were considerably increased at the concentrations of bio-floc 100, 120, and 140% after 90 days. As water quality indicators, the values of total-N, NH₄⁺-N and PO₄^--P were analyzed, and they were significantly decreased at 120 and 140% of bio-floc, compared to the control. The results demonstrated that combination of EM showed the synergic effect on removing N and P.

• 한국물환경학회지
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• 제37권1호
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• pp.47-54
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• 2021

Aerobic granular sludge (AGS) can be classified as a type of self-immobilized microbial aggregates measuring more than 0.2 mm. It offers the option to simultaneously remove COD, N, and P that occur in different zones inside a granule. Also, AGS is characterized by high precipitability, treatability with high organic loading, and high tolerance to low temperature. In this study, a sequencing batch reactor inoculated with AGS (AGS-SBR) is a new advanced wastewater treatment process that was proven to grow AGS with integrated nutrient removal and low C/N ratio. A pilot plant, AGS-SBR with a capacity of 225 ㎥/d was installed at an S sewage treatment plant in Gyeonggi-do. The results of the operation showed that the water quality of the effluent indicated that the value of BOD5 was 1.5 mg/L, CODMn was 11.4 mg/L, SS was 6.2 mg/L, T-N was 13.2 mg/L, and T-P was 0.197 mg/L, and all of these values reliably satisfied an effluent standard (I Area). In winter, the T-N treatment efficiency at a lower temperature of less than 11℃ also showed reliability to meet the effluent standard of the I Area (20 mg/L or less). Analysis of microbial community in AGS showed a higher preponderance of beneficial microorganisms involved in denitrification and phosphorus accumulation compared with activated sludge. The power consumption and sludge disposal cost were reduced by 34.7% and 54.9%, respectively, compared to the domestic SBR type sewage treatment plant with a processing capacity of 1,000 ㎥/d or less.

• 한국토양비료학회지
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• 제45권6호
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• pp.1216-1221
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• 2012

재배과정, 수확, 가공 및 유통 단계에서 당귀의 미생물적 위해요소를 조사하였다. 뿌리, 토양 및 관개수를 포함한 111개의 시료가 생산과정과 유통과정에서 호기성균, B. cereus, coliform, E. coli, L. monocytogenes, Salmonella spp., 와 S. aureus를 조사하기 위해 수집하였다. 재배과정에서 당귀의 뿌리에서 일반세균수는 6.71 log CFU $g^{-1}$ 수준으로 검출되었으며, 대장균군은 4.13 log CFU $g^{-1}$, B. cereus는 3.54 log CFU $g^{-1}$ 수준으로 확인되었다. 수확에서 가공 단계까지 모든 가공 과정에서 대장균군과 B. cereus의 오염을 확인할 수 있었으며, 절단 과정에서 미생물오염도가 높게 확인 되었다. 유통과정 중인 당귀에서 일반세균수는 5.6~6.0 log CFU $g^{-1}$, 대장균군은 2.4~2.6 log CFU $g^{-1}$, B. cereus는 5.4~6.0 log CFU $g^{-1}$ 수준으로 검출되었다. 모든 시료에서 L. monocytogenes, Salmonella spp., S. aureus는 검출되지 않았다. 이러한 결과는 유해미생물의 오염을 감소시키고, 안전한 농산물을 생산하기 위하여 위생적인 토양관리 및 수확 후 관리가 수행되어야 하는 것을 의미한다.