USDA FSIS, FDA BAM, and ISO Culture Methods BD BBL CHROMagar O157 Media

Abstract BBL CHROMagar O157 media (CO) was evaluated for detection of Escherichia coli O157:H7 in raw ground beef and unpasteurized apple cider. The recovery of E. coli O157:H7 on CO was compared to the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM), U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS), and International Organization for Standardization (ISO) reference-plated media using the recommended enrichment broths. Of the 180 food samples tested, 45 were tested using BAM, 45 using the USDA method, and 90 using the ISO method. CO produced comparable results with the reference methods on all matrixes with a sensitivity of 100 and a specificity of 100. No false negatives were found in testing the food matrixes. There was no statistical difference in recovery based on Chi-square analysis. Method agreement for raw ground beef was 85 for the USDA FSIS method and 95 for the ISO method. Method agreement for unpasteurized apple cider was 100 for the ISO and FDA BAM methods. In all cases where method agreement was <100, CO detected more positives than the reference method media. Evaluation of known isolates on CO in inclusivity and exclusivity testing had a sensitivity and specificity of 100. The results of this study demonstrate that CO is an effective medium for the recovery and detection of E. coli O157:H7 in raw ground beef and unpasteurized apple cider using FDA BAM, USDA FSIS, and ISO methods.

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USDA FSIS, FDA BAM, AOAC, and ISO Culture Methods BD BBL CHROMagar Listeria Media

Journal of AOAC International ◽

10.1093/jaoac/92.4.1105 ◽

2009 ◽

Vol 92 (4) ◽

pp. 1105-1117 ◽

Cited By ~ 3

Author(s):

Vicki Ritter ◽

Susan Kircher ◽

Krista Sturm ◽

Patty Warns ◽

Nancy Dick

Keyword(s):

Ground Beef ◽

Food Samples ◽

International Organization ◽

Culture Methods ◽

Department Of Agriculture ◽

False Negatives ◽

Chi Square ◽

Smoked Salmon ◽

Inspection Service ◽

Chi Square Analysis

Abstract BBL CHROMagar Listeria Media (CL) was evaluated for detection of Listeria monocytogenes in raw ground beef, smoked salmon, lettuce, and Brie cheese. The recovery of L. monocytogenes on CL was compared to the U.S. Food and Drug Administration (FDA) Bacteriological Analytical Manual (BAM), U.S. Department of Agriculture (USDA) Food Safety and Inspection Service (FSIS), AOAC, and International Organization for Standardization (ISO) reference-plated media using the recommended pre-enrichments and selective enrichments. Of the 265 food samples tested, 140 were tested using BAM, USDA, or AOAC methods and 125 were tested using ISO methods. CL produced comparable results with the reference methods on all matrixes with a sensitivity of 99.3 and a specificity of 100. No false negatives were found in testing the food matrixes. There was no statistical difference in recovery based on Chi-square analysis. Known isolates were evaluated, and CL had a sensitivity and specificity of 100. The results of this study demonstrate that CL is an effective medium for the recovery and detection of L. monocytogenes in raw ground beef, smoked salmon, lettuce, and Brie cheese using FDA BAM, USDA FSIS, AOAC, and ISO culture methods.

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Addendum: ISO Culture Methods Comparative Testing of BBL CHROMagar Salmonella Prepared Plated Culture Medium

Journal of AOAC International ◽

10.1093/jaoac/92.2.471 ◽

2009 ◽

Vol 92 (2) ◽

pp. 471-480 ◽

Cited By ~ 4

Author(s):

Vicki Ritter ◽

Nancy Dick

Keyword(s):

Culture Medium ◽

Ground Beef ◽

Reference Method ◽

Food Samples ◽

Culture Methods ◽

False Negatives ◽

Chi Square ◽

Shell Eggs ◽

Raw Fish ◽

Method Agreement

Abstract BBL CHROMagar Salmonella (CS) was evaluated for the detection of Salmonella species compared to the International Organization for Standardization (ISO) 6579:2002 reference method media. Raw chicken, raw ground beef, raw fish, lettuce, and shell eggs were evaluated by an independent laboratory. Raw chicken was found to be naturally contaminated with Salmonella; all other matrixes were seeded with Salmonella at a low level. Four Salmonella serovars were used for seeding the food matrixes. A total of 120 food samples were analyzed. The detection and isolation of Salmonella on CS was compared to the ISO culture methods reference media, using the recommended pre-enrichments and selective enrichments. BBL CS produced results comparable to those of the reference methods on all matrixes, resulting in a method agreement of 100 based on the Chi-square results. Known isolates were tested and had a sensitivity of 96.8 and specificity of 94. No false negatives were found in testing the food matrixes. The results of this study demonstrate that BBL CS is an effective medium for the recovery and detection of Salmonella in raw chicken, raw ground beef, raw fish, lettuce, and shell eggs using ISO method 6579.

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Evaluation of the Assurance GDS™ for E. coli O157:H7 Method and Assurance GDS for Shigatoxin Genes Method in Selected Foods: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/88.5.1334 ◽

2005 ◽

Vol 88 (5) ◽

pp. 1334-1348 ◽

Cited By ~ 7

Author(s):

Philip T Feldsine ◽

Shannon T Green ◽

Andrew H Lienau ◽

James Stephens ◽

Markus T Jucker ◽

...

Keyword(s):

Orange Juice ◽

Collaborative Study ◽

Ground Beef ◽

Culture Methods ◽

Chi Square ◽

E Coli ◽

Reference Methods ◽

Uninoculated Control ◽

Chi Square Analysis ◽

Better Than

Abstract A multilaboratory collaborative study was conducted to compare the Assurance GDS™ for E. coli O157:H7 method and the reference culture methods for the detection of E. coli O157:H7 in orange juice, raw ground beef, and fresh lettuce. A separate companion assay, the Assurance GDS for Shigatoxin Genes method was also evaluated with the same test portions. Fifteen laboratories participated in the study. A Chi square analysis of each of the 3 food types at the high, low, and uninoculated control levels was performed. For all foods, the Assurance GDS for E. coli O157:H7 method and the Assurance GDS for Shigatoxin Genes method were equivalent to or better than the reference methods.

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VIDAS® Listeria species Xpress (LSX)

Journal of AOAC International ◽

10.5740/jaoacint.govval04 ◽

2013 ◽

Vol 96 (2) ◽

pp. 242-245 ◽

Cited By ~ 1

Author(s):

Ronald Johnson ◽

John Mills

Keyword(s):

Stainless Steel ◽

Reference Method ◽

Culture Method ◽

Culture Methods ◽

Chi Square ◽

Listeria Species ◽

Standard Culture ◽

Inspection Service ◽

Chi Square Analysis ◽

Positive Results

Abstract The AOAC GovVal study compared the VIDAS®Listeria species Xpress (LSX) to the Health Products and Food Branch MFHPB-30 reference method for detection of Listeria on stainless steel. The LSX method utilizes a novel and proprietary enrichment media, Listeria Xpress broth, enabling detection of Listeria species in environmental samples with the automated VIDAS in a minimum of 26 h. The LSX method also includes the use of the chromogenic media, chromID™ Ottaviani Agosti Agar (OAA) and chromID™ Lmono for confirmation of LSX presumptive results. In previous AOAC validation studies comparing VIDAS LSX to the U. S. Food and Drug Administration's Bacteriological Analytical Manual (FDA-BAM) and the U. S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference methods, the LSX method was approved as AOAC Official Method2010.02 for the detection of Listeria species in dairy products, vegetables, seafood, raw meats and poultry, and processed meats and poultry, and as AOAC Performance Tested Method 100501 in a variety of foods and on environmental surfaces. The GovVal comparative study included 20 replicate test portions each at two contamination levels for stainless steel where fractionally positive results (5–15 positive results/20 replicate portions tested) were obtained by at least one method at one level. Five uncontaminated controls were included. In the stainless steel artificially contaminated surface study, there were 25 confirmed positives by the VIDAS LSX assay and 22 confirmed positives by the standard culture methods. Chi-square analysis indicated no statistical differences between the VIDAS LSX method and the MFHPB-30 standard methods at the 5% level of significance. Confirmation of presumptive LSX results with the chromogenic OAA and Lmono media was shown to be equivalent to the appropriate reference method agars. The data in this study demonstrate that the VIDAS LSX method is an acceptable alternative method to the MFHPB-30 standard culture method for the detection of Listeria species on stainless steel.

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Validation of the Applied Biosystems MicroSEQ® Real-Time PCR System for Detection of E. coli O157:H7 in Food

Journal of AOAC International ◽

10.5740/jaoacint.11-289 ◽

2012 ◽

Vol 95 (5) ◽

pp. 1495-1504 ◽

Cited By ~ 4

Author(s):

Lily Y Wong ◽

Yanxiang Cao ◽

Priya Balachandran ◽

Patrick Zoder ◽

Manohar R Furtado ◽

...

Keyword(s):

Sample Preparation ◽

Real Time ◽

Real Time Pcr ◽

Ground Beef ◽

Reference Method ◽

Test Method ◽

Acid Extraction ◽

Culture Methods ◽

Chi Square ◽

E Coli

Abstract Modern molecular methods offer the advantages of simplicity and short time-to-results compared to traditional culture methods. We describe the validation of a new Real-Time PCR method to detect E. coli O157:H7 in five food matrixes. The complete system consists of the MicroSEQ®E. coli O157:H7 Detection Kit, sample preparation (two sample preparation methods, the PrepSEQ® Nucleic Acid Extraction Kit and the PrepSEQ Rapid Spin Sample Preparation Kit, were validated), the Applied Biosystems 7500 Fast Real-Time PCR instrument, and RapidFinder™ Express software. The test method was compared to the U.S. Department of Agriculture Microbiology Laboratory Guidebook 5.04 reference method for detecting E. coli O157:H7 in 25 g and 375 g ground beef and beef trim, and to the ISO 16654 reference method for detecting E. coli O157:H7 in 25 g spinach, orange juice, and apple juice. The MicroSEQ E. coli O157:H7 Detection Kit showed equivalent detection compared to the corresponding reference method based on Mantel-Haenszel Chi-square statistics for all matrixes tested. An independent validation confirmed these findings on ground beef. The MicroSEQ kit detected all 51 E. coli O157:H7 strains tested and showed good discrimination against an exclusivity panel of 30 strains.

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Validation of iQ-Check E. coli O157:H7 Real-Time PCR Test Kit for Detection of Escherichia coli O157:H7 in Selected Foods

Journal of AOAC International ◽

10.1093/jaoac/92.4.1095 ◽

2009 ◽

Vol 92 (4) ◽

pp. 1095-1104 ◽

Cited By ~ 1

Author(s):

Wendy F Lauer ◽

Sylvie Tymciu ◽

Caroline D Sidi ◽

Pierre Sonigo

Keyword(s):

Real Time ◽

Real Time Pcr ◽

Ground Beef ◽

Reference Method ◽

Target Sequence ◽

Apple Cider ◽

E Coli ◽

Test Kit ◽

Significant Difference ◽

The U.S

Abstract iQ-Check E. coli O157:H7 (Bio-Rad Laboratories, Hercules, CA) is a real-time PCR kit for detection of E. coli O157:H7 from selected foods. Specific fluorescent oligonucleotide probes are used to detect target DNA during the amplification, by hybridizing to the amplicons. These fluorescent probes are linked to a fluorophore which fluoresces only when hybridized to the target sequence. Three foods (ground beef, apple cider, fresh spinach) were selected to compare the performance of iQ-Check E. coli O157:H7 to the U.S. Department of Agriculture-Food Safety and Inspection Service Microbiology Laboratory Guidebook (MLG) reference method for ground beef and the U.S. Food and Drug Administration/Bacteriological Analytical Manual reference method for apple cider and fresh spinach. Three protocols were tested in this study: a shortened 8 h primary enrichment in buffered peptone water (BPW), a 24 h enrichment in BPW, and an enrichment in appropriate reference method enrichment broth. The iQ-Check E. coli O157:H7 method was able to identify more true/confirmed positive samples than the reference method. Inclusivity and exclusivity rates of the method were 100. iQ-Check E. coli O157:H7 performed as expected when minor procedural variations were introduced, validating the ruggedness of the method. There was no significant difference observed in performance over the shelf life of the kit.

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USDA FSIS and FDA BAM Culture Methods BBL CHROMagar Salmonella Prepared Plated and Difco Dehydrated Culture Media

Journal of AOAC International ◽

10.1093/jaoac/92.2.459 ◽

2009 ◽

Vol 92 (2) ◽

pp. 459-470 ◽

Cited By ~ 4

Author(s):

Vicki Ritter ◽

Nancy Dick

Keyword(s):

Culture Media ◽

False Positive Rate ◽

Ground Beef ◽

Reference Method ◽

Chi Square ◽

Shell Eggs ◽

Reference Methods ◽

Raw Fish ◽

Chi Square Analysis ◽

The U.S

Abstract BBL and Difco CHROMagar Salmonella (CS) was evaluated internally and externally for the recovery of Salmonella in raw chicken, raw ground beef, raw fish, lettuce, and shell eggs. The raw chicken and ground beef were processed according to the U.S. Department of Agriculture, Food Safety and Inspection Service reference methods. The raw fish, lettuce, and shell eggs were processed according to the U.S. Food and Drug Administration, Bacteriological Analytical Manual procedures. Only raw chicken was found to be naturally contaminated with Salmonella; all other matrixeswere seededwith an appropriate dilution of organism to achieve fractionally positive results. Salmonella strains were permitted to equilibrate with the culture-negative matrixes for 48 h at 4C. Twenty 25 g samples of each food matrix plus 5 uninoculated samples were processed. CS prepared plates (CS PPM) and laboratory prepared plates from dehydrated culture media (CS DCM) were evaluated with the reference method media. A total of 16 positive cultures were obtained from the raw chicken samples, 17 in the raw ground beef, 18 in the raw fish and lettuce, and 11 in the shell eggs. A Chi-square analysis was performed on each of the food matrixes. BBL CS produced comparable results with the reference methods on all matrixes, resulting in a method agreement of 100 based on the Chi-square results. In testing known isolates the sensitivity and specificity was determined to be 94. Specificity improved to 98 when tetrathionate broth enrichment was used. A negative- and false-positive rate of 6 was found with known isolates. No false negatives were found in testing the food matrixes. The performance of the CS prepared plate and laboratory prepared plate was identical.

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Precollaborative Study of the GeneQuence® Salmonella Assay Using 24-Hour Enrichment Protocols for Detection of Salmonella spp. in Select Foods

Journal of AOAC International ◽

10.1093/jaoac/90.3.725 ◽

2007 ◽

Vol 90 (3) ◽

pp. 725-737 ◽

Cited By ~ 2

Author(s):

Susan Alles ◽

Xuan Peng ◽

Michael Wendorf ◽

Mark Mozola

Keyword(s):

Collaborative Study ◽

False Negative ◽

False Negative Rate ◽

Salmonella Spp ◽

Culture Methods ◽

Department Of Agriculture ◽

Chi Square ◽

Salmonella Assay ◽

Inspection Service ◽

Chi Square Analysis

Abstract New enrichment protocols are described for use with a DNA hybridization (DNAH) method for detection of Salmonella spp. in select foods. GeneQuence® Salmonella, in its original version, utilized a 3-stage enrichment of minimum 42 h duration. New 2-stage procedures of 2428 h duration are described for raw poultry, raw beef, pasteurized egg products, milk chocolate, and dry pet food. In the validation study described here, a total of 345 samples were tested by the abbreviated DNAH method in parallel with either the U.S. Food and Drug Administration's Bacteriological Analytical Manual (FDA/BAM) or U.S. Department of Agriculture-Food Safety and Inspection Service (USDA-FSIS) reference culture procedures. Results showed an overall sensitivity for the DNAH method of 97.1% (false-negative rate 2.9%). There were no false-positive results by the DNAH method; therefore the specificity was 100%. Overall agreement between the DNAH and reference culture methods was 98.5%. There were no significant differences in performance between the DNAH and reference methods for any of the foods tested as determined by Chi-square analysis. It is recommended that the DNAH method be subjected to AOAC collaborative study.

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Validation of the ANSR®E. coli O157:H7 Method for Detection of E. coli O157:H7

Journal of AOAC International ◽

10.5740/jaoacint.15-0309 ◽

2016 ◽

Vol 99 (3) ◽

pp. 705-716 ◽

Cited By ~ 1

Author(s):

Ryan Viator ◽

Susan Alles ◽

Quynh-Nhi Le ◽

Edan Hosking ◽

Evan Meister ◽

...

Keyword(s):

Target Genes ◽

Ground Beef ◽

Reference Method ◽

Single Step ◽

Fluorescence Detector ◽

Method Performance ◽

E Coli ◽

Reference Methods ◽

Inspection Service ◽

The U.S

Abstract A performance validation of the ANSR® for E. coli O157:H7 method was conducted in selected food matrixes. This assay uses selective nicking enzyme amplification technology to amplify target genes. Samples are enriched for 12–24 h and then lysed. The assay is completed within 40 min using real-time detection in a combination incubator/fluorescence detector and software. When 44 distinct strains of Escherichia coli O157:H7 and 6 strains of E. coli O157:NM were tested for inclusivity, all 50 strains produced positive results. In exclusivity testing, 57 strains representing 33 species of closely related Gram-negative bacteria belonging to the Enterobacteriaceae family, including 11 non-H7 O157 strains and shiga toxin-producing E. coli other than O157:H7, were evaluated. All 57 nontarget strains generated negative ANSR assay results. Using 80% lean ground beef and beef trim (approximately 20% fat), ANSR method performance was compared to the U.S. Department of Agriculture, Food Safety and Inspection Service Microbiology Laboratory Guidebook reference culture procedure. ANSR performance with baby spinach and sprout irrigation water was measured against the U.S. Food and Drug Administration Bacteriological Analytical Manual reference method. ANSR method performance was not statistically different to that of the reference methods using two different enrichment options. For ground beef and beef trim, the standard enrichment in modified Tryptone Soya Broth can be analyzed using the ANSR assay with a 1:10 dilution of the enrichment in phosphate-buffered saline and produces equivalent results to the reference method. Additionally, in most matrixes tested (exception is spinach which required 24 h enrichment) the assay offers great efficiency and flexibility over the reference method with a 12–24 h single-step enrichment. Equivalent results were observed at both time points (12 and 24 h) to reference methods. Small changes to the assay parameters minimally affected ANSR method performance. Finally, accelerated stability results from three independently manufactured lots support a shelf-life of 6 months when stored at 4°C.

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Direct 24-Hour Presumptive Enumeration of Escherichia coli 0157:H7 in Foods Using Hydrophobic Grid Membrane Filter Followed by Serological Confirmation: Collaborative Study

Journal of AOAC International ◽

10.1093/jaoac/81.2.403 ◽

1998 ◽

Vol 81 (2) ◽

pp. 403-418 ◽

Cited By ~ 6

Author(s):

Phyllis Entis ◽

◽

D Bryant ◽

J Bryant ◽

R G Bryant ◽

...

Keyword(s):

Escherichia Coli ◽

Membrane Filter ◽

Collaborative Study ◽

Reference Method ◽

Test Method ◽

Cottage Cheese ◽

Apple Cider ◽

Dairy Foods ◽

E Coli ◽

Repeatability And Reproducibility

abstract Fifteen laboratories took part in a collaborative study to validate a method for enumerating Escherichia coli 0157:H7. The method is based on use of a hydrophobic grid membrane filter and consists of 24 h presumptive enumeration on SD-39 Agar and serological confirmation to yield a confirmed E. coli 0157:H7 count. Six food products were analyzed: pasteurized apple cider, pasteurized 2% milk, cottage cheese, cooked ground pork, raw ground beef, and frozen whole egg. The test method produced significantly higher confirmed count results than did the reference method for milk, pork, and beef. Test method results were numerically higher than but statistically equivalent to reference method results for cheese, cider, and egg. The test method produced lower repeatability and reproducibility values than did the reference method for most food/inoculation level combinations and values very similar to those of the reference method for the remaining combinations. Overall, 94% of presumptive positive isolates from the test method were confirmed serologically as E. coli 0157:H7, and 98% of these were also biochemically typical of E. coli 0157:H7 (completed test). Corresponding rates for the reference method were 69 and 98%, respectively. On the basis of the results of this collaborative study and the precollaborative study that preceded it, it is recommended that this method be adopted official first action for enumeration of E. coli 0157:H7 in meats, poultry, dairy foods, infant formula, liquid eggs, mayonnaise, and apple cider

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