• 한국축산식품학회지
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• 제37권6호
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• pp.799-803
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• 2017

In the present study, centrifugation and filtration pretreatments were evaluated to decrease sample preparation time and to improve the sensitivity and specificity of multiplex polymerase chain reaction (PCR) for the detection of low levels of pathogenic Escherichia coli in various foods. Pathogenic E. coli (E. coli NCCP11142, E. coli NCCP14037, E. coli NCCP 14038, E. coli NCCP14039, and E. coli NCCP15661) was inoculated into pork, beef, and baby leafy vegetables at 1, 2, and 3 Log CFU/g. The samples were shaken 30 times (control), then centrifuged or filtered. DNA extracts from the samples were subjected to PCR using the $Powerchek^{TM}$ Diarrheal E. coli 8-plex Detection Kit. In the pork samples, no E. coli was detected in the control samples, while E. coli were detected in 100% of 3-Log CFU/g inoculated and centrifuged samples, and in 100% of 2 and 3-Log CFU/g inoculated, and filtered samples. In the beef samples, all control samples appeared to be E. coli-negative, while E. coli was detected in 50-75% of centrifuged samples, regardless of inoculated level, and in 100% of 2 and 3-Log CFU/g inoculated, and filtered samples. In baby leafy vegetables, E. coli were not detected in 25-50% of the control samples, while E. coli were detected in 0-25% of the centrifuged samples, and 75-100% of the filtered samples, depending on the inoculum amount. In conclusion, filtration pretreatment can be used to minimize sample preparation time, and improve the sensitivity and specificity of rapid detection of pathogenic E. coli in various foods.

• Journal of Nutrition and Health
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• 제12권3호
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• pp.25-32
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• 1979

한국(韓國) 식품가공(食品加工)에 상용(常用)하고 있는 식품첨가물중(食品添加物中)의 유해금속원소(有害金屬元素)의 함량(含量)을 조사검토(調査檢討)하기 위(爲)하여 착향과(着香料) 7종(種), 착색과(着色料)3종(種), 산미과(酸味料)4종(種), 팽장제(膨腸劑)4종(種), 유화제(乳化劑)(2종(種)), 호료(糊料)2종(種), 항산화제(抗酸化劑)2종(種), 강화제(强化劑)2종(種), 조미료(調味料(3종(種)), 식품품질개량제(食品品質改良劑)(10종(種)의 유해금속(有害金屬)을 APDC-MIBK추출법(抽出法)으로 측정(測定)한 결과(結果) 대부분(大部分)의 식품첨가물(食品添加物)은 유해금속(有害金屬을) 비교적(比較的) 적게 함유(含有)하고 있었으나 sodium, carbonate, 식용황색색(食用叢色色), 5호(號), 식용청색색소(食用靑色色素) 1호(號), 식용적색색소(食用赤色色素) 2호(號) 및 면류첨가알카리제는 다소(多少) 다량(多量)으로 함유(含有)하고 있다. 이들 식품첨가물(食品添加物의) 유해금속(有害金雇)의 함량(含量)은 다음과 같다. 1) sodium carbonate Cd: 16.77 $16.77{\mu}g/g.$ Pb: $61.55{\mu}g/g$이었다. 2) 식용황색색소(食用黃色色素) 5호(號)는 Cd: $1.67{\mu}g/g$, Pb: $23.46{\mu}g/g$이었다. 3) 식용청색색소(食用靑色色素) 1호(號)는 Cd: $1.16{\mu}g/g$, Pb: $12.13{\mu}g/g$이었다. 4) 식용적색색소(食用赤色色素) 2호(號)는 Cd: $1.91{\mu}g/g$, Pb: $23.08{\mu}g/g$이었다. 5) 면류 첨가(添加)알카리제는 Cd: $6.11{\mu}g/g$, Pb: $53.85{\mu}g/g$ 이었다.

• Preventive Nutrition and Food Science
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• 제17권1호
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• pp.46-52
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• 2012

This study was performed to investigate the effects of pre-treatment and storage temperature and periods on the quality characteristics of ginger paste. The pH of the ginger paste remained constant during room temperature storage but increased with prolonged refrigerated storage periods. During five months of frozen storage, regardless of pre-treatment, the pH of most of the samples decreased slightly and then remained constant. In the color value of ginger paste stored at room temperature, the samples with and without chemical additives changed in color more prominently than fermented or pasteurized samples. Intriguingly, the color value for samples containing chemical additives changed more dramatically when stored under refrigerated conditions. However, the L, a, and b values of samples stored under frozen storage conditions did not change even after ten months. Most of the samples contained glucose and fructose, except for the fermented samples. The free sugar content of samples slowly decreased with increasing storage periods, while the organic acid content generally decreased also, regardless of sample type. Depending on pre-treatment and storage temperature, the gingerol content of the samples was either retained or decreased with prolonged storage time.

• 환경위생공학
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• 제1권1호
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• pp.59-67
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• 1986

This sanitary survey was carried out to investigate the bacteriological contamination of cooking utensils and foods of moving tavern in eight sample sites of Seoul area. The results of survey were as follows: 1. The counts by means of total bacteria in cooking utensils and food samples by standard plate count method were as follow: $5.6\times10^5$ per gm in dishcloth, $3.1\times10^6$ per ml in dishwater. In food samples, $5.4\times10^5$ per gm in meat was higher than other samples. 2. The average counts total coliform and fecal coliform in samples by MPN method were as follow: $3.4\times10^4$ MPN per 100ml, and $1.3\times10^2$ MPN per 100ml in chopping board, $6.1\times10^4$MPN per gm and $1.0\times10^2$ MPN per gm in dishcloth, $1.8\times10^5$ MPN per 100ml and $6.1\times10^2$ MPN per 100ml in dishwater. In food samples, $3.1\times10^4$MPN per gm and $2.0\times10^2$ MPN per gm in meat was higher than other samples. 3. The counts by means of Pseudomonas in samples by MPN method were as follow: $2.8\times10^3$ MPN per 100ml in chopping board, $4.7\times10^3$ MPN per gm in dishcloth $5.6\times10^3$ MPN per 100ml in dishwater. In food samples, $2.4\times10^3$ MPN per gm in shellfish was higher than other samples. 4. Isolation cases of Food poisoning organisms from samples were as follow: Staphylococci was detected 9 cases $(17.6\%)$ in chopping board, 7 cases $(13.6\%)$ in dishcloth. In food samples, 9 cases $(25.7\%)$ in meat, 1 case $(4\%)$ in fish samples. Salmonella was detected 2 cases $(3.9\%)$ in dishwater, 1 case in meat samples.

• Preventive Nutrition and Food Science
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• 제16권3호
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• pp.261-266
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• 2011

Supercritical $CO_2$ pretreatment before dehydration leads to a faster dehydration rate. The best supercritical $CO_2$ pretreatment conditions for the most effective dehydration were $45^{\circ}C$, 25 MPa and $55^{\circ}C$, 25 MPa. Increasing pressure of the supercritical $CO_2$ pretreatment system tended to accelerate the dehydration rate more than increasing temperature did. Samples pretreated at higher temperatures and pressures showed greater shrinking and pore distribution on scanning electron microscopy. Control samples maintained their cell walls, whereas samples pretreated at higher temperatures and pressures showed more cell disruption, and more pores were observed. Pore sizes of control and pretreated samples were about 100 and $70{\sim}80\;{\mu}m$, respectively. Samples pretreated at higher temperatures and pressures had smaller pores and a denser distribution.

• 한국축산식품학회지
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• 제33권4호
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• pp.549-554
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• 2013

Food safety is important issue for consumers and recently the usage of food ingredients especially food preservatives are limited by regulations. However, some manufacturers use food preservatives instead of improving their hygienic production. Therefore, the levels of sodium benzoate and potassium sorbate of 147 vacuum packaged Kashar (fresh) cheese samples produced in Black Sea Region, Turkey were investigated and some microbiological properties were determined. Research results demonstrated that the production of vacuumed Kashar cheese in Black Sea Region was not standardized for all production periods depending on the microbiological properties. Coliform and E. coli counts detected in the cheese samples showed that necessary hygienic conditions were not provided for Kashar cheese production. Staphylococcus aureus was not determined in the cheese samples. The sodium benzoate and potassium sorbate were analyzed by HPLC-DAD. Potassium sorbate levels (69.39 mg/kg) of Kashar cheese samples were determined to be lower than the maximum permitted concentration of Turkish Food Codex. Although the utilization of sodium benzoate is prohibited by the Codex, the average level of sodium benzoate of cheese samples was detected to be 68.63 mg/kg. Sodium benzoate can be naturally occurred in fresh cheese at concentrations of up to 50 mg/kg.

• 한국축산식품학회지
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• 제43권3호
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• pp.441-453
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• 2023

The objective of this study was to investigate the physicochemical and microbiological characteristics of round of Hanwoo by vacuum packaging film materials, polyvinylidene chloride (PVDC) and ethylene vinyl alcohol (EVOH). The packaged beef samples were stored in refrigerated conditions (2±1℃) for 12 weeks. Physicochemical analysis with pH, surface color, thiobarbituric acid reactive substances (TBARS) values, and volatile basic nitrogen (VBN) values and microbiological analysis with aerobic plate count (APC) and metagenomic analysis of packaged beef samples were performed. The pH and surface color did not change substantially during the 12 weeks and EVOH-packaged beef tended to be lower than those of PVDC-packaged beef. PVDC- and EVOH-packaged samples showed low TBARS and VBN values below standard limits. APC did not exceed 7 Log CFU/g for both samples during storage. In metagenomic analysis, Firmicutes and Lactobacillaceae were dominant phylum and family of the PVDC- and EVOH-packaged beef. In both packaged samples, Dellaglioa algida was the dominant species during storage, with the notable difference being the presence of Lactococcus piscium. Therefore, this study provided the information on the quality of vacuum-packaged beef according to different vacuum films for long-term refrigerated storage.

• 한국식품조리과학회지
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• 제30권5호
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• pp.642-649
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• 2014

We investigated the antioxidant and physicochemical qualities as well as the sensory characteristics, and microbial safety of sunsik containing varied amounts of AF-343, which can help add moisture to the skin and relieve the symptoms of atopic dermatitis. Samples did not show significant differences in pH measurements, but the pH had a tendency to increase with tendencies as increased amounts of AF-343. The total phenolic compound contents and DPPH radical scavenging activity, indicators of biologically active ingredients such as antioxidant, anticancer and antibacterial activity, significantly increased as the amounts of AF-343 increased (p<0.05). In an acceptance test, the samples did not show significant differences, however samples with the 750 mg AF-343 received the highest scores out of all the samples in overall acceptance. All samples were confirmed as microbially safe according to the food code applied to food manufacturers. Aerobic plate counts of the control group were 1.60 log CFU/g, while those of samples with 750 mg AF-343 were 1.70 log CFU/g. E. coli. Pathogenic microorganisms tests were either negative or not detected in all samples.

• Journal of Microbiology and Biotechnology
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• 제34권5호
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• pp.1101-1108
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• 2024

Earlier studies have validated the isolation of extended-spectrum beta-lactamase-producing Salmonella (ESBL-Sal) strains from food. While poultry is recognized as a reservoir for Salmonella contamination, pertinent data regarding ESBL-Sal remains limited. Consequently, the Ministry of Food and Drug Safety has isolated Salmonella spp. from retail meat and evaluated their antibiotic susceptibility and genetic characteristics via whole-genome sequencing. To further elucidate these aspects, this study investigates the prevalence, antibiotic resistance profiles, genomic characteristics, and homology of ESBL-Sal spp. obtained from livestock-derived products in South Korean retail outlets. A total of 653 Salmonella spp. were isolated from 1,876 meat samples, including 509 beef, 503 pork, 555 chicken, and 309 duck samples. The prevalence rates of Salmonella were 0.0%, 1.4%, 17.5%, and 28.2% in the beef, pork, chicken, and duck samples, respectively. ESBL-Sal was exclusively identified in poultry meat, with a prevalence of 1.4% in the chicken samples (8/555) and 0.3% in the duck samples (1/309). All ESBL-Sal strains carried the bla_CTX-M-1 gene and exhibited resistance to ampicillin, ceftiofur, ceftazidime, nalidixic acid, and tetracycline. Eight ESBL-Sal isolates were identified as S. Enteritidis with sequence type (ST) 11. The major plasmid replicons of the Enteritidis-ST11 strains were IncFIB(S) and IncFII(S), carrying antimicrobial resistance genes (β-lactam, tetracycline, and aminoglycoside) and 166 virulence factor genes. The results of this study provide valuable insights for the surveillance and monitoring of ESBL-Sal in South Korean food chain.

• 한국식생활문화학회지
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• 제29권5호
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• pp.444-453
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• 2014

This study investigated the antioxidative activities and quality characteristics of Aster scaber Bibimbap as a home meal replacement with blanching (BASB) or without blanching (ASB) pretreatment. BASB samples at 5.0 g showed higher moisture, crude protein, and ash contents than the control (p<0.05). Color L, a, b-values of samples significantly decreased with increased content of Aster scaber powder (p<0.05). BASB samples showed lower hardness than ASB samples. BASB samples showed higher total phenolic content and DPPH radical scavenging activity than ASB samples. BASB samples showed higher sensory values for color, savory aroma, savory flavor, and aftertaste than ASB samples. Except for glossiness, BASB samples showed higher sensory acceptance scores than ASB samples. Sensory acceptance tests of all samples showed high scores for 'usually like', representing the possibility of successful development of Bibimbap as a home meal replacement, especially that containing blanching pre-treated Aster scaber powder.