• 한국미생물·생명공학회지
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• 제48권2호
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• pp.121-128
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• 2020

Diarrhea is a major public health concern associated with pathogenic Escherichia coli infections. Food-borne pathogenic E. coli can lead to large diarrheal outbreaks and hence, there is a need to estimate the frequency of pathogenic E. coli load in the various types of meat available in markets. In the present study, we classified and characterized diarrheagenic E. coli isolates collected from 399 raw meat samples from retail sources in Korea. Shiga toxin-producing E. coli (STEC) were detected in 11 (9.7%) samples, including nine strains (8.0%) in beef and two strains (1.8%) in chicken. The frequency of the detected virulence markers were as follows: astA, 28.3%; escV,18.6%; eaeA,17.7%; ent, 7.0%; EHEC-hly, 4.4%; stx1, 3.5%; and stx2, 3.5%. We did not observe any typical EPEC, EIEC, or ETEC virulence determinants in any of the samples. The STEC serotype O26 was detected in one sample, but no other serogroups (O91, O103, O128, O157, O145, O111, and O121) were found. Further research is needed to better understand the virulence mechanism of STEC serotypes, their ecology, and prevalence in animals, food, and the environment. These results will help improve risk assessment and predict the sources of food poisoning outbreaks.

• 한국축산식품학회지
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• 제43권6호
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• pp.989-1001
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• 2023

Processed foods containing pork fat tissue to improve flavor and gain economic benefit may cause severe issues for Muslims, Jews, and vegetarians. This study aimed to develop an indirect enzyme-linked immunosorbent assay (iELISA) based on a monoclonal antibody specific to thermal stable-soluble protein in pork fat tissue and apply it to detect pork fat tissue in heat-processed (autoclave, steam, roast, and fry) beef meatballs. To develop a sensitive iELISA, the optimal sample pre-cooking time, coating conditions, primary and secondary dilution time, and various buffer systems were tested. The change in the iELISA sensitivity with different 96-well microtiter microplates was confirmed. The detection limit of iELISA performed with an appropriate microplate was 0.015% (w/w) pork fat in raw and heat-treated beef. No cross-reactions to other meats or fats were shown. These results mean that the iELISA can be used as an analytical method to detect trace amounts of pork fat mixed in beef.

• 한국식품영양과학회지
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• 제31권1호
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• pp.64-68
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• 2002

본 연구는 gum류의 첨가가 우육 patty의 품질에 미치는 영향을 검토하기 위하여 실시하였다. 생육 및 가열육 patty의 수분함량은 대조구가 낮았고, 지방함량은 대조구가 유의하게 높았다. 그리고 생육 patty의 단백질함량은 gum류 첨가구가 대조구보다 높게 나타났다. 생육 patty의 $L^{*}$ 값은 대조구가 gum류 첨가구보다 높았으나, $a^{*}$ 및 $b^{*}$ 값은 patty들 사이에 차이가 없었다. 또 가열육 patty의 $L^{*}$ , $a^{*}$ 및 $b^{*}$ 값은 4종류 patty들 사이에 차이가 없었다. 가열육 patty의 조리수율, 지방보유율 및 보수력은 gum류 첨가구가 대조구보다 높았다. 우육 patty의 경도 및 씹힘성은 대조구와 gum류 첨가구 사이에 차이가 없었으나, 껌성은 gum류 첨가구보다 높게 나타났다. 관능검사 결과 향기, 다즙성 및 전체적인 기호도는 patty들 사이에 유의한 차이가 없었으나, 조직감은 gum류 첨가구가 대조구보다 높았다.

• 한국식품위생안전성학회지
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• 제29권3호
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• pp.228-233
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• 2014

This study was performed to examine antimicrobial resistance of Enterococcus spp. strains from retail raw meat and fish products purchased in 2012. 43 Enterococcus spp. strains were isolated from a total of 207 samples (beef, pork, chicken, fish) with contamination rate of 20.8%. The isolated strains were identified as E. faecalis (22 strains), E. gallinarum, E. hirae (5 strains), E. avium (4 strains), E. faecium (3 strains), E. duram, E. casseliflavus (2 strains). Susceptibility to 10 antibiotics was tested, and the highest resistance was observed to tetracycline. And antimicrobial resistance rates were presented below 20% with most of the other antimicrobial agents. The isolated Enterococci from chicken showed higher resistance also to ciprofloxacin and erythromycin, not only to tetracycline, compared to the isolated Enterococci from beef, pork and fish. Sixteen isolates (37.2%) were sensitive to all antibiotics. Four isolates (9.3%) were resistant to 3 or more antibiotics. Vancomycin-resistant enterococci (VRE) was not identified. According to the results of genetic similarity pattern analysis via PFGE and rep-PCR, Enterococci strains showed different patterns from these collected in 2011. This indicates that there is no genetic similarity among all the strains.

• 한국축산식품학회지
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• 제38권5호
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• pp.1019-1028
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• 2018

The crust that inevitably forms on dry-aged beef is usually trimmed and discarded before sale. The aim of this study was to explore methods for utilizing this crust in processed meat products. Four sirloins were dry-aged for 28 d at $4^{\circ}C$ (75% relative humidity). The crust obtained from the surface of the sirloins after completion of dry aging was lyophilized. Patties were prepared without added crust (control) or with 5% w/w crust, aerobically packaged, and stored at $4^{\circ}C$ for 7 d. Electronic nose analysis indicated that the volatile profile differed significantly between the patties with and without crust. Compared to the control patties, patties containing crust had higher flavor, tenderness, juiciness, and acceptability scores in a sensory panel evaluation (all p<0.05). In addition, patties with crust were less hard, gummy, and chewy than the control patties after 3 and 7 d of storage (all p<0.05). The number of total aerobic bacteria was higher in raw patties with crust than in the control patties during the storage (p<0.05). However, no pathogens were detected. 2-Thiobarbituric acid reactive substance values of patties containing crust were significantly lower than those of control patties after 2 and 6 d of storage (both p<0.05). Thus, crust from dry-aged beef can enhance the flavor by providing beefy and palatable flavor without a long period of dry aging.

• 한국식품과학회지
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• 제16권3호
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• pp.291-296
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• 1984

국내산 및 수입(輸入) 쇠고기의 지방질(脂肪質)을 분별정량(分別定最)하고 조리(調理)직후 및 조리후 저장(貯藏)중에 일어나는 지방질의 산패(酸敗)및 향미(香味)의 변화과정을 규명하였다. 곰국용과 로스구이용 원료육(原料肉), 조리육(調理肉), 저장육(貯藏肉)에 있어서 총지방질(總脂肪質)과 중성지방질(中性脂肪質)의 함량은 수입쇠고기보다 국내산 쇠고기에서 더 많았다. 조리 및 저장중 총지방질과 인지방질(燐脂肪質)의 함량은 일반적으로 감소하는 경향을 나타냈다. 쇠고기의 조리방법(調理方法)을 달리하여 관능검사(官能檢査)를 실시한 결과 곰국용 쇠고기와 로스구이용 쇠고기 모두 국내산과 수입육(輸入肉) 사이에 유의적(有意的)인 차이가 있었다. 기호척도(嗜好尺度)에 있어서는 로스구응한 쇠고기의 경우 유의적(有意的)인 차이가 없었으나 곰국의 경우 조리직후의 국내산 쇠고기와 저장후의 수입 쇠고기 사이에 유의적(有意的)인 차이가 있었다. 조리(調理)후 모든 시료의 TBA값은 완만한 증가를 보였으나 조리후 저장(貯藏)한 시료에서는 급격한 증가를 나타냈다. TBA값이 증가함에 따라 관능검사치(官能檢査値)는 감소하는 경향을 보였다.

• Animal Bioscience
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• 제34권5호
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• pp.904-913
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• 2021

Objective: Marbling or intramuscular fat (IMF) has been widely reported to directly impact the sensory acceptance of meat. This study was carried out to determine the physical and sensory characteristics of ribeye, Longissimus dorsi steaks obtained from four different cattle breeds namely Wagyu, Angus, Brahman, and Malaysian local beef, the Kedah-Kelantan (KK). Methods: The degree of marbling was determined by using an established combined camera-image analysis technique while instrumental texture determination was carried out by using Warner-Bratzler shear force analysis. Sensory evaluation of the beef steaks was performed following a quantitative descriptive analysis incorporating 10 trained consumer panelists. Results: Wagyu was found to possess the highest (p<0.05) percentage of IMF at 33.90% and the lowest shear force (raw = 5.61 N/㎟; cooked = 14.72 N/㎟) followed by Angus (20.87%), Brahman (12.17%), and KK (p<0.05, 6.86%). The difference in sensory properties of the four steaks was evident, with Wagyu appearing to be highly correlated with most sensory attributes measured namely sustained buttery, tooth-packing, chewiness, juiciness, tenderness, mouthfeel, oiliness, and overall acceptability. The Malaysian local beef, KK was found to be less acceptable (p<0.05), although most of its sensory attributes were found similar (p>0.05) in appearance, aroma, texture, juiciness, and flavour to the cooked steak from Angus and Brahman. Conclusion: This present study demonstrated the role of IMF in determining the quality and sensory acceptance of beef from different cattle breeds. These data have provided new information and further understanding on the physical and sensory quality of Malaysian local beef.

• Animal Bioscience
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• 제37권5호
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• pp.918-928
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• 2024

Objective: The adulteration of raw beef (BMr) with dog meat (DMr) and pork (PMr) becomes a serious problem because it is associated with halal status, quality, and safety of meats. This research aimed to develop an effective authentication method to detect non-halal meats (dog meat and pork) in beef using metabolomics approach. Methods: Liquid chromatography-high resolution mass spectrometry (LC-HRMS) using untargeted approach combined with chemometrics was applied for analysis non-halal meats in BMr. Results: The untargeted metabolomics approach successfully identified various metabolites in BMr DMr, PMr, and their mixtures. The discrimination and classification between authentic BMr and those adulterated with DMr and PMr were successfully determined using partial least square-discriminant analysis (PLS-DA) with high accuracy. All BMr samples containing non-halal meats could be differentiated from authentic BMr. A number of discriminating metabolites with potential as biomarkers to discriminate BMr in the mixtures with DMr and PMr could be identified from the analysis of variable importance for projection value. Partial least square (PLS) and orthogonal PLS (OPLS) regression using discriminating metabolites showed high accuracy (R² >0.990) and high precision (both RMSEC and RMSEE <5%) in predicting the concentration of DMr and PMr present in beef indicating that the discriminating metabolites were good predictors. The developed untargeted LC-HRMS metabolomics and chemometrics successfully identified non-halal meats adulteration (DMr and PMr) in beef with high sensitivity up to 0.1% (w/w). Conclusion: A combination of LC-HRMS untargeted metabolomic and chemometrics promises to be an effective analytical technique for halal authenticity testing of meats. This method could be further standardized and proposed as a method for halal authentication of meats.

• 한국식품조리과학회지
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• 제23권2호통권98호
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• pp.187-194
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• 2007

이 연구는 시중 유통 브랜드 한우와 비브랜드 한우의 품질 특성을 조사하기 위하여 이화학적, 미생물학적, 관능적, 평가로 품질특성을 알아보고자 하였다. 채끝을 기준으로 할 때 국내산 브랜드 소고기의 100 g 당 평균 가격은 7,200원, 비브랜드 소고기은 2,974원이었다. 브랜드 한우에서는 지방의 함량이 높은 경향을 보였지만, 브랜드 한우와 비브랜드 한우간에는 유의적 차이가 없는 것으로 나타났다. 국내산 브랜드 한우와 비브랜드 한우 모두 pH는 약 5.27로 차이가 없는 것으로 나타났다. 브랜드 한우의 lightness(Hunter L value)가 조금 더 높은 경향을 보였으나 유의적인 차이는 나타나지 않았다. 가열육에서의 조직감을 보면 비브랜드 한우가 gumminess, fracturability chewiness에서 브랜드 한우보다 높은 경향을 나타냈으며, 이중 gumminess, fracturability에서는 브랜드 한우와 비브랜드 한우간에 유의적 차이가 있었다. 미생물적 안전성 차원에서 볼 때 국내산 브랜드 한우의 비브랜드 한우와 차이가 나지 않는 것으로 나타났다. 신선육의 관능평가에서는 육색, 지방색, 근내지방도, 향미, 종합적 기호도에 있어서 모두 유의적 차이가 나는 것으로 나타났다. 또한 조리 후 관능평가에서도 브랜드 한우가 비브랜드 한우에 비해 색, 향미, 다즙성, 연도, 맛, 씹힙성, 종합적 기호도가 우수한 것으로 나타났다.

• Journal of Microbiology and Biotechnology
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• 제2권3호
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• pp.183-188
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• 1992

A soil bacterium which produces raw starch-digesting $\beta$-amylase in culture medium, has been screened from soils. One strain, isolated and identified as Bacillus polymyxa No. 26, was selected as a $\beta$-amylase producing bacterium. Morphological and biological characteristics of the strain were found to be similar to those of a strain belonging to B. polymyxa. The electron microscopic observations of the bacterial vegetative cells and sporulated cells were extensively done to know the corelation between the enzyme synthesis and sporulation. When the bacterium was cultured on the appropriate media (3% dextrin, 0.3% beef extract, 0.5% polypeptone, 1% yeast extract and 0.3% NaCl at pH 7.0 for 4 days) raw starch-digestible $\beta$-amylase was produced extracellularly. This strain produced 130 units of $\beta$-amylase per ml in a culture medium containing 3% dextrin at $30^\circ{C}$. This value is compared to those of other $\beta$-amylase-producing strains. The optimum pH and temperature for crude enzymes were pH 6.5 to 7.0 and $50^\circ{C}$, respectively. The enzymes were stable between pH 5.5 and 9.0 for 30 min at $45^\circ{C}$.