• 한국수산과학회지
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• 제8권2호
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• pp.107-117
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• 1975

Alaska pollack caught in the Northern Pacific Ocean and frozen aboard vessel are skipped to the plant and processed into frozen fillets. In the present paper quality changes during thwaing, refreezing and storage at $-20^{\circ}C$ are discussed. Natural, running-water, vacuum and steam thawing were employed as thawing methods. And contact plate, air blast, immersion in dry ice-alcohol solution freezing and storage at $-5^{\circ}C$ were applied to refreeze the thawed fillets. As quality factors content of drip released, salt-extractable protein, VBN, DNA in the drip and pH were determined. In addition, bacteriological tests were also carried out along with the whole process. In thawing of round material, the vacuum thawing was more effective than any other method, resulting in drip, salt-extractable protein $(N\%)$, VBN and DNA as $4.4\%,\;1.82\%,\;16.21mg\%$ and $13.70\;{\mu}g/ml$, respectively. Storage at $-5^{\circ}C$ as refreezing method yielded lower in drip and DNA content but similar to or slightly higher in both salt-extractable protein and VBN, which might postulate that the quality of the frozen fillet depends not largely on the secondary freezing but on the conditions of thawing and primary freezing. It seemed that most of the bacterial flora in thawed fillet came from skin and viscera of fish, worker's hands, utensils and other processing facilities, since sanitary indicative bacteria were not detected in the frozen flesh of round Alaska pollack. Bacterial quality of fillet varied with thawing methods, vacuum thawing appeared more sanitative compared with other methods as natural, running-water, and steam thawing. Bacterial colonies isolated from the thawed fillet were composed of $73.8\%$ Gram negative rod shape, $4.9\%$ Gram positive rod shape, $18.0\%$ cocci, and $3.3\%$ yeast. Decreasing rate of coliform group of the fillet during the storage at $-20^{\circ}C$ for 30 days was more than $70\%$ and that of plate count was less than of coliform group.

• Journal of Microbiology and Biotechnology
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• 제27권5호
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• pp.995-1004
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• 2017

Culture-dependent methods, such as heterotrophic plate counting (HPC), are usually applied to evaluate the bacteriological quality of hemodialysis water. However, these methods cannot detect the uncultured or viable but non-culturable (VBNC) bacteria, both of which may be quantitatively predominant throughout the hemodialysis water treatment system. Therefore, propidium monoazide (PMA)-qPCR associated with HPC was used together to profile the distribution of the total viable bacteria in such a system. Moreover, high-throughput sequencing of 16S rRNA gene amplicons was utilized to analyze the microbial community structure and diversity. The HPC results indicated that the total bacterial counts conformed to the standards, yet the bacteria amounts were abruptly enhanced after carbon filter treatment. Nevertheless, the bacterial counts detected by PMA-qPCR, with the highest levels of $2.14{\times}10^7copies/100ml$ in softener water, were much higher than the corresponding HPC results, which demonstrated the occurrence of numerous uncultured or VBNC bacteria among the entire system before reverse osmosis (RO). In addition, the microbial community structure was very different and the diversity was enhanced after the carbon filter. Although the diversity was minimized after RO treatment, pathogens such as Escherichia could still be detected in the RO effluent. In general, both the amounts of bacteria and the complexity of microbial community in the hemodialysis water treatment system revealed by molecular approaches were much higher than by traditional method. These results suggested the higher health risk potential for hemodialysis patients from the up-to-standard water. The treatment process could also be optimized, based on the results of this study.

• 한국수산과학회지
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• 제50권4호
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• pp.343-351
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• 2017

Sanitary evaluation of seawater and Pyropia sp. laver collected from the five major laver growing areas in Korea was performed four times over the course of a year. The seawater quality in four of these five areas was regarded as the clean area according to Korean criteria, but the seawater at one investigation site in Seoheon area was found to exceed the standard for fecal coliform. In the bacteriological safety analysis of laver (raw source), the percentages of samples not conforming to Chinese criteria at the five sites were 55.6% (Seocheon), 70.0% (Shinan), 81.8% [Jindo (Haenam)], 63.6% (Wando), and 28.6% [Goheung (Jangheung)]. Pathogenic bacteria were not detected in all laver samples. The food safety of laver (raw source) based on heavy metal concentration was confirmed using Korean criteria; the concentrations of heavy metals in laver samples collected from the major laver growing areas were 0.008-0.632 mg/kg wet weight (ww) lead, 0.024-0.137 mg/kg ww cadmium, 0.908-2.892 mg/kg ww total arsenic, and 0.003-0.013 mg/kg ww total mercury. Therefore, pollution source management and periodic monitoring of heavy metals may be required to improve the food safety of laver produced in these laver growing areas.

• 한국수산과학회지
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• 제16권1호
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• pp.31-36
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• 1983

부산시내에 산재하고 있는 70여개소의 약수터중 11개소를 선정하여 이들의 수질관리에 필요한 기초자료를 얻고자 1981년 10월부터 1982년 9월까지 132개 시료를 취하여 대장균군, 분편계대장균, 일반생균수 및 대장균군의 조성을 시험한 결과를 요약하면 다음과 같다. 1. 11개소의 대장균군 최확수의 중앙치는 구포가 93/100ml로 제일 높았고, 수영, 연산동, 성지곡이 68/100ml 우동과 대신동이 59/100ml, 전포동, 망미동은 43/100ml 영도, 동래가 33/100ml그리고 감만동이 13.3/100ml로 제일 낮았으며 이들 중 6개소가 50/100ml 이상이었다. 2. 분편계대장균 최확수의 중앙치는 영도가 12.1/100ml으로 제일 불결하였고, 수영을 비롯한 8개소는 9.1/100ml, 우동은 6.4/100ml이었으며 감만동이 제일 깨끗하였다. 3. IMViC 반응에 의한 대장균군의 조성은 Escherichia coli group이 $7.64\%$, Klebsiella aerogenes group이 $16.78\%$, Citrobacter freundii group이 $42.86\%$, 기타가 $32.72\%$로 나타났었다. 4. 일반생균수의 중앙치는 $48{\sim}4.4{\times10}^2/ml$의 넓은 분포로서 보사부(1963)의 수질기준에 절반 지역이 초과되었다.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1513-1513
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• 2001

Present Food Legislation compels dairy industry to carry out analyses in order to guarantee the food safety and quality of products. Furthermore, in many cases industry pays milk according to bacteriological or/and nutritional quality. In order to do these analyses, several expensive instruments are needed (Milkoscan, Fossomatic, Bactoscan). NIRS technology Provides a unique instrument to deal with all analytical requirements. It offers as main advantages its speed and, specially, its versatility, since not only allows determine all the parameters required in milk analysis, but also allows analyse other dairy products, like cheese or whey. The objective of this study is to develop NIRS calibration equations to predict several quality parameters in goat milk, cheese and whey. Three sets of 123 milk samples, 190 cheese samples and 109 whey samples, have been analysed in a FOSS NIR Systems 6500 I spectrophotometer equipped with a spinning module. Milk and whey were analysed by folded transmission, using circular cells with gold surface and pathlength of 0.1 m, while intact cheese was analysed by reflectance using standard circular cells. NIRS calibrations were obtained for the prediction of chemical composition in goat milk, for fat (r$^2$=0.92; SECV=0.20%), total solids (r$^2$=0.95: SECV=0.22%), protein (r$^2$=0.94; SECV=0.07%), casein (r$^2$=0.93; SECV=0.07%) and lactose (r$^2$=0.89; SECV=0.05%). Moreover, equations have been performed to determine somatic cells (r$^2$=0.81; SECV=276.89%) and total bacteria (r$^2$=0.58; SECV=499.32%) counts in goat milk. In the case of cheese, calibrations were obtained for the prediction of fat (r$^2$=0.92; SECV=0.57), total solids (r$^2$=0.80; SECV=0.92%) and protein (r$^2$=0.70; SECV=0.63%). In whey, fat (r$^2$=0.66; SECV=0.08%), total solids (r$^2$=0.67; SECV=0.19%) and protein (r$^2$=0.76; SECV=0.07%) NIRS equations were obtained. These results proved the viability of NIRS technology to predict chemical and microbiological parameters and somatic cells count in goat milk, as well as chemical composition of goat cheese and whey.

• 한국근적외분광분석학회:학술대회논문집
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• 한국근적외분광분석학회 2001년도 NIR-2001
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• pp.1610-1610
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• 2001

Microbiological examination of silage is of little value in gauging the outcome of silage, and so chemical analysis is more reliable and meaningful indicator of quality. On the other hand chemical assessments of the principal fermentation products provide an unequivocal basis on which to judge quality. Livestock require energy, protein, minerals and vitamins from their food. While fresh forages provide these essential items, conserved forages on the other hand may be deficient in one or more of them. The aim of the conservation process is to preserve as many of the original nutrients as possible, particularly energy and protein components (Woolford, 1984). Silage fermentation is important to preservation of forage with respect of feeding value and animal performance. Chemical and bacteriological changes in the silo during the fermentation process can affect adversely nutrient yield and quality (Moe and Carr, 1984). Many of the important chemical components of silage must be assayed in fresh or by extraction of the fresh material, since drying either by heat or lyophilisation, volatilises components such as acids or nitrogenous components, or effects conversion to other compounds (Abrams et al., 1987). Maize silage dorms the basis of winter rations for the vast majority of dairy and beef cattle production in Uruguay. Since nutrient intake, particularly energy, from forages is influenced by both voluntary dry matter intake and digestibility; there is a need for a rapid technique for predicting these parameters in farm advisory systems. Near Infrared Reflectance Spectroscopy (NIRS) is increasingly used as a rapid, accurate method of evaluating chemical constituents in cereals and dried forages. For many years NIRS was applied to assess chemical composition in dry materials (Norris et al., 1976, Flinn et al., 1992; Murray, 1993, De Boever et al., 1996, De la Roza et al., 1998). The objectives of this study were (1) to determine the potential of NIRS to assess the chemical composition of dried maize samples and (2) to attempt calibrations on undried samples either for farm advisory systems or for animal nutrition research purposes in Uruguay. NIRS were used to assess the chemical composition of whole - plant maize silage samples (Zea mays, L). A representative population of samples (n = 350) covering a wide distribution in chemical characteristics were used. Samples were scanned at 2 nm intervals over the wavelength range 400-2500 nm in a NIRS 6500 (NIRSystems, Silver Spring, MD, USA) in reflectance mode. Cross validation was used to avoid overfitting of the equations. The optimum calibrations were selected on the basis of minimizing the standard error of cross validation (SECV). The calibration statistics were R$^2$ 0. 86 (SECV: 11.4), 0.90 (SECV: 5.7), 0.90 (SECV: 16.9) for dry matter (DM), crude protein (CP), acid detergent fiber (ADF) in g kg$\^$-1/ on dry matter, respectively for maize silage samples. This work demonstrates the potential of NIRS to analyse whole - maize silage in a wide range of chemical characteristics for both advisory farm and nutritive evaluation.

• 한국식품위생안전성학회지
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• 제15권2호
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• pp.61-67
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• 2000

1995년(4월과 5월), 1997년(5월과 7월) 및 1999년(1월)에 경부 .호남 고속도로 및 중부 . 영동 고속도로의 20개 ,휴게소의 김밥, 햄버거, 호도과자 및 자장면에 대한 계절별 위생 실태와 조리 형태에 의한 미생물적 안전성 시험을 실시한 결과 식중독균은 검출되지 않았으나 대장균과 많은 수의 대장균군 세균이 검출되어, 고속도로 휴게소에서 판매되고 있는 식품의 위생 실태가 매우 불량함을 알수 있었다. '95년 김밥 시료에서는 전 제품에서 대장균군(8.8$\times$10 4~6.6$\times$10 5 cells/g)과 대장균이 검출되었고,'95년 햄버거 또한 전 제품에서 대장균군(1.8$\times$10 2~4.7$\times$10 4 cells/g)이 검출되었다. '97년 시료에서는 김밥은 22곳 제품 중 16곳 제품에서 대장균이 양성이었고, 대장균군은 21곳 제품에서 검출되었다. '97년 햄버거는 14곳 제품 중 7곳 제품에서 1.7$\times$10 2~1.9$\times$10 7 cells/g의 대장균군이, 2곳 제품에서 대장균이 양성으로 나타나서 김밥과 햄버거의 위생 상태는 매우 불량하였다. 호도과자는 조사 대상 6곳 제품 중 대장균군과 대장균이 모두 검출되지 않아 위생 상태가 양호하였다. 반면 자장면은 6곳 제품 중 3곳 제품에서 7.1$\times$10 2~2.0$\times$10 3 cells/g수준의 대장균군이 검출되고 대장균은 검출되지 않았다. '95년과 '97년 김밥 시험 결과와 '99년 결과를 비교할 때 기온이 높은 계절의 위생 관리에 더욱 주의해야 함을 알 수 있었다. 김밥과 기타 식품의 세균학적 품질을 비교한 결과, 김밥 >햄버거 >자장면 >호도과자의 순으로 나타나 김밥과 햄버거와 같은 복합재료를 사용하는 식품의 경우에 더 많은 오염이 일어날 수 있으므로 조리 .가공 및 유통 과정의 엄격한 미생물절-안전성 관리가 요구된다.

• 농업생명과학연구
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• 제44권2호
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• pp.7-15
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• 2010

이 연구는 2009년 1월부터 9월까지 총 4회(1월, 4월, 7월 9월) 사천만에서 해수와 표층퇴적물의 세균학적 이화학적 특성을 조사한 것이다. 조사기간 중에 수온은 $5.3{\sim}24.9^{\circ}C$(평균 $17.7{\pm}0.4^{\circ}C$), 투명도는 1.4~2.5m(평균 $1.8{\pm}0.5m$), 부유물질 농도는 16.2~35.8mg/L(평균 $24.2{\pm}2.2mg/L$), 화학적산소요구량 (COD)는 $1.42{\sim}3.29mgO_2/L$(평균 $2.06{\pm}0.55mgO_2/L$), 용존산소(DO)는 6.7~9.5mg/L(평균 $7.9{\pm}0.6mg/L$)로 각각 조사되었다. 대장균군과 분변계대장균의 검출 범위는 <1.8~7,900 MPN/100mL (GM 214.7 MPN/100mL)과 <1.8~330 MPN/ 100mL (GM 9.7 MPN/100mL)로 각각 나타났다. 대장균군은 시료의 75.0%, 분변계대장균은 57.1%가 각각 양성을 나타내었다. 대장균군에 대한 분변계대장균의 양성율은 76.2%로 나타났다. 조사기간 중에 사천만에서의 표층퇴적물의 수분함량, 강열감량, COD 및 AVS의 평균값은 $53.28{\pm}2.58%$, $9.38{\pm}0.42%$, $14.23{\pm}3.36mgO_2/g$, $0.09{\pm}0.07mgS/g$로 각각 조사되었다.

• 한국식품저장유통학회지
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• 제16권6호
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• pp.971-976
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• 2009

건강 웰빙식품의 하나로서 수요가 증가하고 있는 새싹채소류는 미생물학적 관점에서 생산단계별 위해분석과 안전성 기준이 부재한 실정이다. 본 연구에서는 생산현장에서 새싹채소의 재배공정별 미생물학적 오염도를 분석 평가하였다. 새싹채소 종자의 일반세균수 및 대장균군수는 각각 3.04~5.21 log CFU/g, 1.80~3.86 log CFU/g의 범위로 나타났으며, 소독유무에 관계없이 재배기간 동안 일반세균(6.99~8.26 log CFU/g) 및 대장균군수(3.70~7.15 log CFU/g)는 증가하였고, 최종 새싹채소에서도 높은 수치를 나타내었다. 소독된 종자의 발아 후 전 단계에서는 식중독균이 검출되지 않았으나, 종자소독을 하지 않은 국내산 무와 유채에서 E. coli가 검출되었고, 국내산 적무에서 E. coli와 식중독균인 Bacillus cereus 및 Listeria monocytogenes가 검출되었다. 따라서 종자생산에서부터 새싹채소의 생산 전 단계에 걸친 HACCP 가이드라인을 마련하여 중점적으로 관리하는 것이 필요하다.

• 한국수산과학회지
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• 제43권5호
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• pp.406-414
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• 2010

The impact of rainfall events on the sanitary indicator bacteria density of the shellfish-growing waters in Geoje Bay and Jaran Bay in Korea was investigated. The shellfish-growing area in Geoje Bay, which is a nearly closed basin, was not affected significantly, except near the stream mouth after 11.5 mm of rainfall in 1 day. However, most of the shellfish-growing water in the bay was polluted by fecal coliform bacteria after rain as heavy as 43.0 mm, and the levels of fecal indicator bacteria in some of the sea near the coast did not recover completely until 24 hours after the rainfall. By contrast, in Jaran Bay, which has no significant pollution source in the drainage area, although 9.3-490 MPN/100 mL of fecal coliform bacteria were detected near the stream mouth after rainfall of 33.5 and 81.0 mm, a very low level of the indicator bacteria was detected in the designated shellfish-growing area. During the investigation, the correlations between the sanitary indicator bacteria density and physical parameters, such as salinity and turbidity, were evaluated. Both the total coliform and fecal coliform densities were inversely correlated with salinity. Turbidity was positively correlated with the indicator bacteria density. The survey results suggest that for more efficient management of the shellfish-growing areas located in coastal areas, such as shellfish harvesting after rainfall, a detailed investigation of the effects of rainfall on the bacterial water quality in each growing area is needed.