Incidence of Staphylococcus aureus and Escherichia coli in Ground Beef, Broilers and Processed Meats in Pretoria, South Africa

1994 ◽  
Vol 57 (4) ◽  
pp. 305-310 ◽  
Author(s):  
S. M. VORSTER ◽  
R. P. GREEBE ◽  
G. L. NORTJÉ
Keyword(s):  
Escherichia Coli ◽  
South Africa ◽  
Staphylococcus Aureus ◽  
Ground Beef ◽  
Processed Meat ◽  
Processed Meats ◽  
E Coli ◽  
Plate Counts ◽  
Meat Samples ◽  
And Staphylococcus Aureus

Three types of processed meats (vienna sausages, shoulder ham, and cervelat), ground beef and broilers were purchased from 17 different supermarkets in the Pretoria area (South Africa) during 1991. The 232 samples were analyzed for the presence of Escherichia coli and Staphylococcus aureus, with total aerobic plate counts (APCs) also being determined. Escherichia coli was found in 74.5% of the ground beef samples, in 79.1% of the broilers, and in 27.7% of the processed meats. Staphylococcus aureus was found in 23.4% ground beef, 39.5% broiler and 7.1% processed meat samples. The total APCs ranged from as low as log10 1 CFU/g of sample (shoulder ham) to as high as log10 12.1 CFU/g (ground beef). No identifiable relationship between the total APCs and the occurrence of E. coli and/or S. aureus was evident. This study confirms the view that E. coli and S. aureus are frequent contaminants of meat, with South Africa being no exception.

Bacteriological Evaluation of Retail Ground Beef, Frozen Beef Patties, and Cooked Hamburger

1977 ◽  
Vol 40 (6) ◽  
pp. 378-381 ◽  
Author(s):  
C. L. DUITSCHAEVER ◽  
D. H. BULLOCK ◽  
D. R. ARNOTT
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Fast Food ◽  
Ground Beef ◽  
Frozen Ground ◽  
E Coli ◽  
Beef Patties ◽  
Plate Counts ◽  
Bacteriological Evaluation ◽  
G 28

A total of 108 samples of fresh refrigerated ground beef, 99 samples of frozen hamburger patties, and 107 fried hamburgers, purchased from retail stores and fast-food outlets in Ontario, were analyzed for their bacteriological quality. About 44% of non-frozen ground beef samples had aerobic plate counts exceeding 50 million/g; 50 of 108 samples (46.3%) contained Staphylococcus aureus and 46 of these 50 samples (88%) exceeded 1000 organisms/g; 43 of 108 samples were positive for Escherichia coli with 38 samples (88.4%) exceeding 500 organisms/g. About 19% of frozen hamburger patties had aerobic plate counts in excess of 10 million/g; 93 of 99 samples (93.9%) contained S. aureus with 83 of these samples (89.3%) exceeding 1000 organisms/g; 28 of 99 samples were positive for E. coli with 7 of these samples (25%) exceeding 500 organisms/g. About 96.3% of fried hamburger samples had aerobic plate counts of less than 10,000/g.

Effect of Irradiation Temperature on Inactivation of Escherichia coli O157:H7 and Staphylococcus aureus†

2001 ◽  
Vol 64 (10) ◽  
pp. 1624-1626 ◽  
Author(s):  
DONALD W. THAYER ◽  
GLENN BOYD
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Gamma Radiation ◽  
Gamma Irradiation ◽  
Ground Beef ◽  
Irradiation Temperature ◽  
Escherichia Coli O157 ◽  
E Coli ◽  
And Staphylococcus Aureus

The resistance of Escherichia coli O157:H7 and Staphylococcus aureus in ground beef to gamma radiation was significantly (P < 0.05) higher at subfreezing temperatures than above freezing. Ground beef was inoculated (ca. 2 × 108 CFU/g) with five isolates of either E. coli O157:H7 or S. aureus and subdivided into 25-g samples, vacuum packaged in barrier pouches, and tempered to 20, 12, 4, 0, −4, −12, −20, −30, −40, or −76°C before gamma irradiation. The studies were repeated twice. The D10-values for both of these pathogens increased significantly at subfreezing temperatures, reaching maxima at approximately −20°C. The D10-values for E. coli O157:H7 at 4 and −20°C were 0.39 ± 0.04 and 0.98 ± 0.23 kGy, respectively. The D10-values for S. aureus at 0 and −20°C were 0.51 ± 0.02 and 0.88 ± 0.05 kGy, respectively.

Comparison of the Effects of Silver in Nanostructured and Ultrahigh Diluted Form on Growth and Volatile Compounds Produced by Escherichia coli and Staphylococcus aureus

2020 ◽  
Vol 10 (3) ◽  
pp. 316-329
Author(s):  
Fateme Mirzajani ◽  
Amin Hamidi
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Life Cycles ◽  
Gas Chromatography Mass Spectrometry ◽  
Untreated Sample ◽  
E Coli ◽  
Volatile Metabolites ◽  
Octyl Acetate ◽  
Volatile Organic ◽  
And Staphylococcus Aureus

Introduction: In this project, the growth and volatile metabolites profiles of Escherichia coli (E. coli ) and Staphylococcus aureus were monitored under the influence of silver base chemical, nanoparticle and ultra-highly diluted compounds. Materials & Methods: The treatments were done for 12000 life cycles using silver nanoparticles (AgNPs) as well as ultra-highly diluted Argentum nitricum (Arg-n). Volatile organic metabolites analysis was performed using gas chromatography mass spectrometry (GC-MS). The results indicated that AgNPs treatment made the bacteria resistant and adapted to growth in the nanoparticle condition. The use of ultra-highly diluted Arg-n initially increased growth but it decreased later. Also, with the continuous usage of these materials, no more bacterial growth was observed. Results: The most important compounds produced by E. coli are Acetophenone, Octyl acetate, Styrene, 1,8-cineole, 4-t-butyl-2-(1-methyl-2-nitroethyl)cyclohexane, hexadecane and 2-Undecanol. The main compounds derived from S. aureus are Acetophenone,1,8-cineole, Benzaldehyde, 2-Hexan-1-ol, Tridecanol, Dimethyl Octenal and tetradecane. Acetophenone and 1,8-cineole were common and produced by both organisms. Conclusion: Based on the origin of the produced volatiles, main volatiles percentage of untreated sample is hydrocarbon (>50%), while bacteria treatments convert the ratio in to aldehydes, ketones and alcohols in the case of AgNPs, (>80%) and aldehydes, ketones and terpenes in the case of Arg-n (>70%).

Food Poisoning Potential of Artificially Contaminated Vacuum Packaged Sliced Ham in Sandwiches1

1981 ◽  
Vol 44 (6) ◽  
pp. 430-434 ◽  
Author(s):  
JAMES E. STEELE ◽  
MICHAEL E. STILES
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Storage Temperature ◽  
Food Poisoning ◽  
Microbial Competition ◽  
Growth And Survival ◽  
E Coli ◽  
Enteropathogenic Bacteria ◽  
Test Conditions ◽  
And Staphylococcus Aureus

Ham sandwiches inoculated with a mixture of five enteropathogenic bacteria, Bacillus cereus, Clostridium perfringens. Escherichia coli, Salmonella typhimurium and Staphylococcus aureus, were held at 30, 21 and 4 C for up to 24 h. Food poisoning potential was judged by the growth and survival of the inoculated pathogens. Major differences were observed between new and old (30 days of storage at 4 C) ham samples. On new ham, all enteropathogens were able to grow except C. perfringens, whereas on old ham, with high microbial competition. the pathogens survived but did not grow. Severe storage temperature abuse was necessary to develop a food poisoning potential in new ham samples. The safety of old ham was attributed to the competitive microflora that grew in the ham during storage at 4 C for 30 days. Infective pathogens, E. coli and S. typhimurium, either survived or increased in numbers under all test conditions. The safety of vacuum packaged sliced ham for use in sandwiches, in its present market form, was indicated by these studies.

Distribution of Coliphages in Various Foods

1986 ◽  
Vol 49 (12) ◽  
pp. 944-951 ◽  
Author(s):  
J. E. KENNEDY ◽  
C. I. WEI ◽  
J. L. OBLINGER
Keyword(s):  
Escherichia Coli ◽  
Food Samples ◽  
Fecal Coliforms ◽  
Bacterial Indicators ◽  
Processed Meats ◽  
E Coli ◽  
Plate Counts ◽  
The Relationship

The distribution of coliphages in various foods and the relationship between the incidences of coliphages and bacterial indicators were investigated. A total of 120 food samples comprising twelve products and including fresh meats, shellfish, vegetables and processed meats, were analyzed for indigenous coliphages using Escherichia coli hosts C, C-3000 and B. Bacterial analyses included enumeration of E. coli, fecal coliforms and coliforms, as well as aerobic plate counts and Salmonella analyses. Coliphages were detected (≥10 PFU/100 g) in 56% of samples and eleven of twelve products. Coliphages, E. coli, fecal coliforms and coliforms were recovered at a level of at least 30 organisms per 100 g in 43, 43, 68 and 81% of samples, with overall mean recoveries of 13, 19, 93 and 4300 organisms/100 g, respectively. Highest and lowest recoveries of coliphages and E. coli were from fresh meats and vacuum-packaged processed meats, respectively. Significant nonparametric correlations between coliphages, E. coli, fecal coliforms and coliforms were found among all food samples.

Fate of Pathogens Inoculated onto Vacuum-Packaged Sliced Hams to Simulate Contamination During Packaging1

1979 ◽  
Vol 42 (6) ◽  
pp. 464-469 ◽  
Author(s):  
M. E. STILES ◽  
L.-K. NG
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Salmonella Typhimurium ◽  
Bacillus Cereus ◽  
Clostridium Perfringens ◽  
Subsequent Treatment ◽  
Vacuum Packaging ◽  
E Coli ◽  
Survival And Growth ◽  
And Staphylococcus Aureus

Ham and chopped ham from two manufacturers were contaminated with five enteropathogens: Bacillus cereus, Clostridium perfringens, Escherichia coli, Salmonella typhimurium and Staphylococcus aureus, at time of slicing and vacuum-packaging, to simulate contamination by manufacturer. Subsequent treatment of the samples, representing sound and undesirable retail handling and consumer use conditions, indicated marked differences in the fate of the pathogens between these products and within product type between the two manufacturers. Greatest differences were observed between the chopped ham products. All pathogens, except C. perfringens, grew actively in fresh ham and chopped ham with abusive holding at 30 and 21 C. After storage at 4 or 10 C for 30 days, B. cereus and C. perfringens were no longer detected, even after subsequent holding at 30 or 21 C for 24 h. E. coli survival and growth was variable, S. typhimurium survived well and grew under some conditions and S. aureus was generally inhibited at high levels of competition.

Bacteriological Survey of Frozen Meat Ravioli Produced at Establishments Under Federal Inspection

1983 ◽  
Vol 46 (8) ◽  
pp. 710-713
Author(s):  
DOUGLAS F. CAMPBELL ◽  
MARTHA Y. WORKMAN ◽  
GEORGE W. KRUMM ◽  
RALPH W. JOHNSTON
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Production Line ◽  
Microbiological Quality ◽  
Slow Freezing ◽  
Geometric Means ◽  
E Coli ◽  
Plate Counts ◽  
Product Sets

During visits to 20 federally inspected establishments producing meat ravioli, 577 production line samples and 480 finished product units were collected for bacteriological analyses. Four types of finished, packaged ravioli were encountered: (a) whole ravioli boiled at least 5 min; (b) raw pasta stuffed with a cooked filling; (c) only the meat component cooked; and (d) uncooked ravioli. The microbiological quality of frozen ravioli was affected more by the filling than the pasta. Slow freezing resulted in increased bacterial levels in the finished product. For the boiled ravioli, 100% of the finished product sets contained less than 50 coliforms per g, four of five sets had less than one Escherichia coli per g, and 100% had fewer than one Staphylococcus aureus per g. Four of five sets of packaged boiled ravioli had aerobic plate counts (APC) of less than 10,000 per g. For the raw pasta with a cooked filling-type ravioli, the geometric means of 9 sets were: coliforms, 47 per g; E. coli, 6.7 per g; S. aureus, 10 per g; and APC, 170,000 per g. For the ravioli with only the meat component cooked, the geometric means of 27 sets were: coliforms, 190 per g; E. coli, 1.8 per g; S. aureus, 3.9 per g; and APC, 300,000 per g. For uncooked ravioli, the geometric means of 7 sets were: coliforms, 490 per g; E. coli, 19 per g; S. aureus, 5.7 per g; and APC, 690,000 per g. Only one finished ravioli unit in 480 contained Salmonella.

scholarly journals Detex for Detection of Escherichia coli O157 in Raw Ground Beef and Raw Ground Poultry

2001 ◽  
Vol 84 (3) ◽  
pp. 752-760 ◽  
Author(s):  
Yvette M Henry ◽  
Nandini Natrajan ◽  
Wendy F Lauer
Keyword(s):  
Escherichia Coli ◽  
False Positive Rate ◽  
Ground Beef ◽  
Escherichia Coli O157 ◽  
Department Of Agriculture ◽  
E Coli ◽  
Metal Plating ◽  
Positive Rate ◽  
Meat Samples ◽  
Inspection Service

Abstract A method for detection of Escherichia coli O157 in beef and poultry is presented. The method is antibody-based and uses a patented antibody-specific metal-plating procedure for the detection of E. coli O157 in enriched meat samples. Both raw ground beef and raw ground poultry were tested as matrixes for the organism. The sensitivity and specificity of the assay were 98 and 90%, respectively. The accuracy of the assay was 96%. Overall, the method agreement between the E. coli O157 Detex assay and the U.S. Department of Agriculture/Food Safety Inspection Service method was 96%. Sample temperature upon loading of the apparatus was critical to the observed false-positive rate of the system.

Sensitivity analysis of Escherichia coli and Staphylococcus aureus of mixed salad vegetables during washing step at packing house

2020 ◽  
Author(s):  
Sukhuntha Osiriphun ◽  
Phichaya Poonlarp ◽  
Danai Boonyakiat ◽  
Patcharin Raviyan
Keyword(s):  
Escherichia Coli ◽  
Staphylococcus Aureus ◽  
Sensitivity Analysis ◽  
Assessment Model ◽  
Health Food ◽  
E Coli ◽  
Global Trend ◽  
Washing Process ◽  
Fresh Cut ◽  
And Staphylococcus Aureus

Fresh cut vegetables are a source of minerals, vitamins, and phytonutrients that are convenient foods for consumers which are following the global trend of inclination toward health food. In terms of food safety, contamination of vegetables with microorganisms can occur at multiple points along the supply chain. This study was conducted to investigate the risk factors of Escherichia coli and Staphylococcus aureus which contaminate freshly cut vegetables during production (receiving, washing, centrifuging, and packing areas) by using a statistical method for sensitivity analysis and an exposure assessment model complying with the @RiskTM software program. At washing step, the numbers of S. aureus found in the vegetables and water were 0.79 ±1.76 Log cfu/g and 0.68±1.52 Log cfu, respectively. For the equipment, the hand, and the table swabbing samples, the numbers of S. aureus were 0.48±1.07 Log cfu/25 cm2, 1.81±1.69 Log cfu/25 cm2 , and 0.54±1.21 Log cfu/25 cm2 , respectively. An amount of E. coli of 0.48±1.07 Log cfu/25 cm2 was found in the table swabbing samples at the packing area. E.coli and S. aureus were not found in any of the mixed fresh-cut salad samples; therefore, the product samples could be considered safe for consumers. The result of the sensitivity analysis showed that the temperature and pH of water samples were the important factors in the washing process. The suggested interventions included monitoring and maintaining the water temperature at 5°C; also, maintaining the pH of water between 6.5 and 7.5 could help to reduce pathogen contamination of freshly cut vegetables.

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