June 24, 2011
A Comparative Evaluation of the Aerobic Procedure for Lactic
Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates with
Two Reference Methods for the Enumeration of Lactic Acid
Bacteria in Food and Environmental Surfaces
Kiel Fisher, Erin Crowley, Patrick Bird, Megan Boyle, Katherine Goetz,
M. Joseph Benzinger Jr., Mark Juenger, Travis Huffman, James Agin, David Goins
Q Laboratories, Inc.
1400 Harrison Avenue
Cincinnati, OH 45214
A validation study of the Aerobic Procedure for Lactic Acid Bacteria (PLAB) with 3M™ Petrifilm™ Aerobic Count (AC) Plates for the
enumeration and detection of lactic acid bacteria was conducted at Q Laboratories, Inc., Cincinnati, Ohio. The PLAB counts were
compared to the counts obtained by the agars used in two reference methods: The Compendium of Methods for the Microbiological
Examination of Foods, Chapter 19 and ISO 15214: Microbiology of food and animal feeding stuffs—Horizontal method for the
enumeration of mesophilic lactic acid bacteria—Colony-count technique. The Compendium reference agar, All Purpose Tween agar
plus 2% sucrose and bromocresol purple (APTS) and the ISO reference agar, deMan, Rogasa, Sharpe plus bromocresol purple (MRS)
were used in the in the analysis of both food and environmental swab samples. Four food matrices and one environmental surface
were used in the comparative evaluation: salad dressings, ready to eat (RTE) salads, RTE meats, raw meats and stainless steel
surfaces. For those matrices that were inoculated, various brands of each matrix were spiked with Lactobacillus fermentum ATCC
14931 or Weissella viridescens ATCC 12706 at two target recovery levels on 3M Petrifilm AC Plates: a low level of 1–15 CFU/ plate and
a medium level of 15–75 CFU/ plate. Natural lactic acid bacteria contamination was recovered in five brands of RTE meat and in all
brands of raw meat. A paired t-test, comparing the PLAB procedure and the reference methods at varying time points, was conducted
at the 95% confidence level. Statistically comparable mean log values were determined for salad dressings, RTE salads, RTE meats,
and stainless steel surfaces. The PLAB procedure demonstrated reliability as a rapid and selective quantitative method for the
enumeration of lactic acid producing bacteria.
This report presents the analytical results for comparison of the Aerobic Procedure for Lactic Acid Bacteria (PLAB) with
3M™ Petrifilm™ Aerobic Count (AC) Plates to agars used in The Compendium of Methods for the Microbiological Examination
of Foods, Chapter 19 and ISO 15214: Microbiology of food and animal feeding stuffs—Horizontal method for the enumeration of
mesophilic lactic acid bacteria—Colony-count technique. All analyses were conducted at Q Laboratories, Inc. (Cincinnati, OH).
3M Petrifilm AC Plates and Aerobic Lactic Bacteria Broth were provided by 3M (Minneapolis, MN).
Q Laboratories, Inc. is an independent company and is not affiliated with, nor a subsidiary of 3M. Q Laboratories, Inc. was contracted to perform an independent study by and
for 3M and the data generated by Q Laboratories, Inc. during the execution of the study does not represent an endorsement of any product(s) by Q Laboratories, Inc.
Page 1
Materials and Methods
The methodology for this study was followed as outlined in the protocol: Comparison of a 3M™ Petrifilm™ Aerobic Count Plate
Method with Three Methods for the Enumeration of Lactic Acid Bacteria in Food and Environmental Samples, provided by 3M.
The study objective was to evaluate the performance of the Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™
Aerobic Count (AC) Plates to the ISO and Compendium Reference Methods for detecting and enumerating lactic acid bacteria.
The following matrices were analyzed: salad dressings, ready to eat (RTE) salads, RTE meats, raw meats, and stainless steel
surfaces. A detailed list of the brands used in the food analysis is presented in Table A.
Table A. Matrix Details
Identification
Salad Dressings
Caesar 1
Brand
Cardini’s Caesar Dressing
RTE Salads
Mustard Potato 1
Meijer Markets Mustard Potato Salad
Caesar 2
Newman’s Own Caesar Dressing
Mustard Potato 2
Grandma’s Mustard Potato Salad
LoFat Caesar 1
Cardini’s Light Caesar Dressing
Mustard Potato 3
Kroger Mustard Potato Salad
LoFat Caesar 2
Ken’s Steak House Light Caesar Dressing
American Potato 1
Grandma’s Potato Salad with Egg
Ranch 1
Kroger Creamy Ranch Dressing
American Potato 2
Meijer Markets American Potato Salad
Ranch 2
Ken’s Steak House Ranch Dressing
American Potato 3
Kroger American Potato Salad
LoFat Ranch 1
Kroger Lite Creamy Ranch Dressing
Macaroni 1
Kroger Macaroni Salad
LoFat Ranch 2
Kraft Light Ranch Reduced Fat Dressing
Macaroni 2
Meijer Macaroni Salad
Catalina 1
Kraft Classic Catalina Dressing Plus Dip
Macaroni 3
Grandmas’ Macaroni Salad
Catalina 2
Kroger California French Dressing
Bean 1
Kroger Baked Beans
Blue Cheese 1
Kraft Roka Brand Blue Cheese Dressing
Bean 2
Gordon Food Services Baked Beans
Blue Cheese 2
Kroger Chunky Blue Cheese Dressing
Bean 3
Meijer Baked Beans
Blue Cheese 3
Ken’s Steak House Chunky Blue Cheese Dressing
Coleslaw 1
Meijer Cole Slaw
Zesty Italian 1
Kroger Zesty Italian Dressing
Coleslaw 2
Kroger Cole Slaw
Zesty Italian 2
Kraft Zesty Italian Dressing
Coleslaw 3
Grandma’s Cole Slaw
RTE Meats
O/R Turkey 1
Sara Lee Fresh Ideas Oven Roasted Turkey Breast
Raw Meats
Ground Turkey 1
Honeysuckle White Ground Turkey 93/7
O/R Turkey 2
Kroger Deli Thin Sliced Oven Roasted Turkey Breast
Ground Turkey 2
Kroger Ground Turkey 85/15
Roast Beef 1
Kroger Deli Thin Sliced Roast Beef
Chicken 1
Tyson All Natural Chicken Breast Tenderloins 85/15
Roast Beef 2
Private Selection Homestyle Slow Roasted Roast Beef
Chicken 2
Perdue Fresh Ground Chicken
O/R Chicken 1
Private Selection Homestyle Slow Roasted Chicken Breast
Ground Beef 1
Kroger Ground Sirloin 90/10
O/R Chicken 2
Sara Lee Fresh Ideas Oven Roasted Chicken Breast
Ground Beef 2
Laura’s Lean Ground Beef 92/8
Smoked Ham 1
Private Selection Smokehouse Hickory Ham
Steak 1
Kroger Beef Top Sirloin
Smoked Ham 2
Kroger Deli Think Sliced Smoked Ham
Steak 2
Kroger Beef Bottom Round Steak Choice
Culture Preparation and Inoculation of Test Portions
Replicates of each matrix varied by food or surface type and were inoculated with Lactobacillus fermentum ATCC 14931 or
Weissella viridescens ATCC 12706 at two target recovery levels on 3M Petrifilm AC Plates: a low level of 1–15 colony forming
units (CFU)/plate and a medium level of 15–75 CFU/plate. To prepare salad dressings and RTE salads for inoculation, the
suspensions of L. fermentum and W. viridescens were prepared in deMan, Rogasa, Sharpe broth (MRS) with 1.0% glucose. The
L. fermentum inoculum was incubated aerobically for 24 ± 2 hours at 35 ± 2°C and the W. viridescens inoculum was incubated
microaerophilically for 24 ± 2 hours at 35 ± 2°C. Twenty-five 1g sample portions were inoculated, mixed thoroughly, and held
for 48 ± 6 hours at 10°C to allow the organism to equilibrate within the matrix. For the analysis of RTE meats, L. fermentum
and W. viridescens inocula were prepared in MRS broth and incubated for 24 ± 2 hours at 35 ± 2°C. Twenty-five gram sample
portions were inoculated, mixed thoroughly, and held in a CO2 atmosphere to simulate packaging conditions for 48 ± 6 hours at
10°C. Following the equilibration step for all food matrices, 25 ± 1g test portions were diluted 1:10 with 0.1% peptone water.
If necessary, subsequent dilutions were made in 90mL of 0.1% peptone water to achieve the target recovery levels on PLAB.
Additionally, naturally contaminated brands of both RTE and raw meats were diluted in 0.1% peptone water until target recovery
levels were achieved.
Page 2
For the analysis of stainless steel environmental surfaces, sixteen 1" x 1" surface areas per organism were inoculated with a
dilution of a L. fermentum or W. viridescens broth culture. The L. fermentum inoculum was prepared using Brain Heart Infusion
Broth and incubated aerobically for 24 ± 2 hours at 35 ± 2°C. The W. viridescens inoculum was prepared in MRS and incubated
microaerophilically for 24 ± 2 hours at 35 ± 2°C. The inoculated surfaces were left to dry at ambient temperature for 18 ± 2
hours prior to sampling. For each organism, eight surface areas were sampled using environmental swabs pre-moistened with
Dey-Engley Neutralizing broth (D/E) and eight surface areas were sampled using environmental swabs pre-moistened with
Letheen Broth (LB). The surface areas were sampled in both horizontal and vertical motions. After sampling, the D/E swabs
were placed into a test tube containing 9mL of D/E and the LB swabs were placed into a test tube containing 9mL of LB.
Subsequent dilutions of these samples were prepared in 9mL test tubes of either D/E or LB to achieve the target recovery levels
on 3M™ Petrifilm™ Aerobic Count (AC) Plates.
Aerobic Procedure for Lactic Acid Bacteria (PLAB) with 3M Petrifilm AC Plates Method
For the PLAB procedure, a 2.0mL aliquot of sample was transferred to a test tube containing 2.0mL of Lactic Bacteria Broth.
After vortexing the solution, a 1.0mL aliquot (0.5mL of sample and 0.5mL of Lactic Broth) was plated onto the 3M Petrifilm
AC Plate. PLAB plates were assayed in quadruplicate and incubated aerobically at 35 ± 2°C for food samples and 25 ± 2°C
for environmental samples for up to 72 ± 3 hours. Halos (acid zones) with and without associated colonies on PLAB plates
were enumerated after 24 ± 2 hours, 48 ± 3 hours, and 72 ± 3 hours of incubation. The presence of colonies with associated gas
bubbles were recorded after 72 ± 3 hours of incubation. For those RTE and raw meat samples that were naturally contaminated,
isolated colonies recovered from the PLAB plates were identified by transferring to tryptic soy agar (TSA) and incubated for 24
± 2 hours at 35 ± 2°C. Final organism identifications were achieved by the VITEK Anaerobe Identification (ANI) method.
Compendial and ISO Reference Methods
For the Compendial method procedure using All Purpose Tween agar plus 2% sucrose and bromocresol purple (APTS), 1.0mL
sample aliquots were pour plated in duplicate and incubated aerobically at 25 ± 2°C for up to 72 ± 3 hours. In addition to APTS
pour plates, salad dressing and stainless steel environmental samples were spread plated onto APTS using 0.25mL sample
aliquots. For the ISO reference method procedure using MRS plus bromocresol purple, 1.0mL sample aliquots were pour plated
in duplicate and incubated anaerobically at 35 ± 2°C. Two sets of MRS pour plates were prepared, one set incubated for 48 ± 3
hours and the other set incubated for 72 ± 3 hours. For each reference agar, colonies with and without halos were enumerated
after 48 ± 3 hours and 72 ± 3 hours. After the 72 hour enumeration, a representative colony from each sample plate was
transferred to MRS broth containing a Durham tube to detect gas production and was incubated at 35 ± 2°C for 5 to 7 days.
Results and Discussion
For the statistical analysis, a paired t-test for two sample means was calculated to analyze statistical differences between the PLAB
counts and reference agar counts at varying time points. The PLAB and reference agar time points used in the statistical analyses
are listed in Table B. The t-tests were calculated using counts across all brands and organisms for each inoculation level within the
matrices. Two procedures were used to obtain the values used in the statistical comparison. For the first method (Method 1), one
PLAB replicate from each brand and organism was compared to one reference agar replicate from each brand and organism. The
PLAB counts were converted to a count per milliliter by multiplying the 0.5mL value by a factor of two. The count per milliliter
values were converted to a Log10 values and compared to single reference agar counts converted to Log10 values in the t-test. For
the second method (Method 2), all four PLAB replicates and both reference agar replicates were used in the t-test calculation. Two
3M Petrifilm AC Plate replicates were added together and the second two 3M Petrifilm AC Plate replicates were added together
to produce two count per milliliter values. The two counts calculated values were converted to Log10 values and averaged. The
Page 3
reference agar counts were converted to Log10 values and averaged. The averaged Log10 values from the PLAB method were
compared to averaged Log10 values from each of the reference agars.
Table B.
Method and Time Points Used in Statistical Analysis
48 Hour 3M™ Petrifilm™ AC Plate Counts vs. 48 Hour APTS Pour Plate Counts
48 Hour 3M™ Petrifilm™ AC Plate Counts vs. 72 Hour APTS Pour Plate Counts
48 Hour 3M™ Petrifilm™ AC Plate Counts vs. 72 Hour APTS Pour Plate Counts
72 Hour 3M™ Petrifilm™ AC Plate Counts vs. 72 Hour MRS Counts
72 Hour 3M™ Petrifilm™ AC Plate Counts vs. 72 Hour MRS Counts
Salad Dressings
For the 24 hour time point, colonies with associated halos were observed on the low level W. viridescens PLAB plates and
medium level W. viridescens PLAB plates had complete yellowing of the agar after 24 hours. The L. fermentum low and medium
level PLAB plates had no colonies or acid zones at 24 hours. Statistically comparable log values were observed comparing
48 hour 3M™ Petrifilm™ Aerobic Count (AC) Plate counts vs. 48 hour APTS pour plate counts at both levels using both
statistical procedures. A detailed list of t-test results for salad dressings is presented in Table 4 of Appendix 1.
RTE Salads
For the 24 hour time point, colonies with associated halos were observed on the low level W. viridescens PLAB plates. Medium
level L. fermentum and W. viridescens PLAB plates were completely yellow after 48 hours. At the 48 and 72 hour time point,
PLAB plates with colonies had associated halos and gas bubbles. Statistically comparable log values were observed comparing
72 hour 3M Petrifilm AC Plate counts vs. 72 hour MRS counts at the medium inoculation level using both statistical procedures.
Statistically comparable log values were observed comparing 72 hour 3M Petrifilm AC Plate counts vs. 72 hour APTS pour plate
counts at the medium inoculation level using t-test Method 2. A detailed list of t-test results for RTE salads is presented in Table
8 of Appendix 1.
RTE Meats
Colonies with associated halos were observed on PLAB plates from the naturally contaminated Private Selection Smokehouse
Hickory Ham. All low level PLAB plates had colonies with associated halos and gas production at the 48 hour time point. All
medium level PLAB plates were completely yellow at the 48 hour time point and had evidence of gas production. Statistically
comparable log values were calculated for the medium level 48 hour 3M Petrifilm AC Plate counts vs. 48 hour APTS pour plate
counts, 48 hour 3M Petrifilm AC Plate counts vs. 72 hour APTS pour plate counts, 72 hour 3M Petrifilm AC Plate counts vs.
72 hour APTS pour plate counts, and 72 hour 3M Petrifilm AC Plate counts vs. 72 hour MRS counts time points using both
t-test methods. L. acidophilus at an acceptable confidence level, L. jensenii at a very good confidence level, and L. cellobiosus
at an excellent confidence level were identified using the VITEK ANI method. A detailed list of t-test results for RTE meats is
presented in Table 11 of Appendix 1.
Raw Meats
At the 24 hour time point, PLAB plates were completely yellow with no associated colonies. At the 48 hour time point, PLAB
plates had colonies with associated gas production. APTS and MRS were overgrown with bacillus and an accurate enumeration
of lactic organisms could not be completed. L. acidophilus, L. jensenii, and L. casei were identified using the VITEK ANI
method at a low discrimination confidence level. A detailed list of PLAB counts for raw meats is presented in Table 12 of
Appendix 1. Due to overgrowth of the competing bacillus, no statistical comparisons were conducted for the raw meats.
Page 4
Stainless Steel Environmentals
Colonies with associated acid zones and gas production were observed on LAB plates at the 48 hour time period and complete
yellowing of the agars occurred at the 72 hour time point. Statistically comparable log values were calculated for the 48 hour
3M™ Petrifilm™ Aerobic Count (AC) Plate counts vs. 48 hour APTS pour plate counts comparison using both t-test methods. A
detailed list of t-test results for stainless steel environmental surface swabs is presented in Table 17 of Appendix 1.
Observations
The method comparison results obtained in the evaluation demonstrate the reliability of the PLAB procedure as an easy-to-use
method for the enumeration and detection of lactic acid organisms in a variety of foods and on stainless steel environmental
surfaces. The method requires a simple plating procedure and eliminates the lengthy gas production confirmation procedure
used in the reference methods. The PLAB method reduces the cost of sample preparation by eliminating the need for producing
and sterilizing reference method agars and eliminates costly materials needed to create and maintain an anaerobic environment
for MRS. The initial appearance of acid zones on PLAB is an accurate early indicator of the presence of lactic acid organisms
as acid zones were always observed surrounding typical red colonies. Colony associated gas production was observed on each
PLAB plate which is a distinct advantage over the reference procedures. The low inoculum level PLAB plates produced distinct
zones and colonies sooner than the medium level PLAB plates. It was often observed that the medium level did not have distinct
acid zones, instead the agar turned completely yellow and colonies were faint. When enumerating lactic organisms from matrices
with a high volume of non-target bacteria, the PLAB plates were easier to accurately enumerate compared to APTS. APTS often
had overgrowth of bacillus and other non- target bacteria, which made enumerating colonies with acid zones challenging. This
gives PLAB an advantage as only true lactic acid producing organisms and no bacillus was observed on 3M Petrifilm AC Plates.
3M and Petrifilm are trademarks of 3M.
Page 5
APPENDIX 1
Page 6
Page 7
0
Zesty Italian 2
* Acid zones
0
0
Blue Cheese 3
0
Blue Cheese 2
Zesty Italian 1
0
0
Blue Cheese 1
Catalina 1
Catalina 2
0
0
LoFat Ranch 2
0
0
0
Ranch 1
Ranch 2
LoFat Ranch 1
0
0
LoFat Caesar 1
LoFat Caesar 2
0
0
0
Zesty Italian 2
Caesar 1
0
Zesty Italian 1
Caesar 2
0
0
Blue Cheese 1
Blue Cheese 2
0
Catalina 2
Blue Cheese 3
0
0
Catalina 1
0
0
Ranch 2
LoFat Ranch 1
0
Ranch 1
LoFat Ranch 2
0
0
LoFat Caesar2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Caesar 2
LoFat Caesar 1
0
0
Caesar 1
B
A
Dressing
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
C
24 Hour
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D
0
0
2
1
1
0
0
67
23
1
21
1
0
3
0
0
0
0
0
0
0
0
17
4
1
0
0
0
0
0
A
1
1
3
6
1
0
0
69
16
1
19
5
1
1
0
0
0
0
0
0
0
0
21
3
0
0
0
0
0
0
B
0
1
2
1
0
0
0
83
20
1
21
2
0
1
0
0
0
0
0
0
0
0
24
3
0
0
0
0
0
0
C
48 Hour*
0
0
0
3
1
0
0
80
11
0
17
7
0
4
0
0
0
0
0
0
0
0
20
3
0
3
0
0
0
0
D
3
6
3
4
1
0
2
93
63
4
54
6
1
13
0
0
1
1
0
1
0
0
45
15
2
2
0
0
2
0
A
2
8
6
9
1
2
2
90
57
2
36
8
1
22
0
0
0
0
3
0
0
0
44
9
0
0
1
0
2
0
B
0
2
6
4
2
0
2
87
59
5
57
7
1
17
0
0
1
0
1
0
2
0
42
9
0
0
0
1
6
0
C
72 Hour*
3
4
4
9
1
2
1
96
39
4
58
8
2
11
0
0
0
0
1
1
0
0
50
6
1
5
0
0
0
0
D
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
A
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
B
0
0
0
2
1
0
0
30
22
0
16
2
1
4
0
0
0
0
0
0
0
0
13
0
0
0
0
0
0
0
A
0
0
0
2
0
0
1
23
18
1
23
4
1
4
0
0
0
0
0
0
0
0
10
0
0
0
0
0
1
0
B
72 Hour
APTS (0.25mL)
48 Hour
Replicate
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 1. Salad Dressing Results — Lactobacillus fermentum
Low Level
Medium Level
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
A
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
B
9
20
25
11
8
13
10
216
116
11
110
18
6
20
1
1
0
4
1
1
0
0
50
2
1
3
0
3
8
3
A
7
17
26
13
6
11
19
177
119
13
100
26
9
21
3
3
0
4
3
1
1
1
40
1
4
2
1
0
4
1
B
72 Hour
APTS (1.0mL)
48 Hour
10
25
21
13
19
16
20
289
143
17
99
17
4
18
4
1
1
0
2
0
4
1
20
12
0
23
1
0
9
0
A
8
22
30
19
21
12
18
301
156
18
106
22
6
26
1
3
0
0
1
0
4
2
30
12
0
16
3
0
13
0
B
17
33
29
26
28
16
15
317
152
28
166
19
7
38
5
12
4
3
1
7
20
1
123
32
4
36
4
1
49
1
A
10
33
26
21
27
21
15
306
150
26
159
30
11
46
8
13
0
4
3
3
21
2
117
37
6
35
6
1
31
0
B
72 Hour
MRS (1.0mL)
48 Hour
Page 8
0
Zesty Italian 2
* Acid zones
0
0
Blue Cheese 3
0
Blue Cheese 2
Zesty Italian 1
0
0
Blue Cheese 1
Catalina 1
Catalina 2
0
0
LoFat Ranch 2
0
0
0
Ranch 1
Ranch 2
LoFat Ranch 1
0
0
LoFat Caesar 1
LoFat Caesar 2
0
0
0
Zesty Italian 2
Caesar 1
1
Zesty Italian 1
Caesar 2
5
4
Blue Cheese 1
Blue Cheese 2
3
Catalina 2
Blue Cheese 3
0
4
Catalina 1
8
7
Ranch 2
LoFat Ranch 1
3
Ranch 1
LoFat Ranch 2
0
0
LoFat Caesar2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2
4
4
2
4
1
9
8
0
0
0
0
0
0
0
Caesar 2
LoFat Caesar 1
0
0
Caesar 1
B
A
Dressing
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
4
3
0
8
0
8
6
6
0
0
0
0
0
C
24 Hour
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
4
6
0
8
0
8
10
7
0
0
0
0
0
D
0
25
60
45
33
165
2
135
120
62
1
0
0
0
0
0
2
9
11
6
28
0
36
20
4
1
0
1
0
0
A
0
15
72
65
29
200
4
154
113
63
2
0
0
0
0
0
3
5
10
8
45
1
25
12
1
0
0
0
0
0
B
0
27
82
71
21
213
3
187
134
66
5
0
0
0
0
0
0
14
11
2
45
0
35
16
8
1
0
0
0
0
C
48 Hour*
0
25
95
69
18
210
3
167
120
53
1
0
0
0
0
0
2
8
8
1
40
0
29
20
10
2
0
0
0
0
D
3
25
60
45
34
171
3
135
123
65
3
0
0
0
0
0
2
9
11
6
28
0
36
21
5
1
0
1
0
0
A
2
17
73
66
32
203
4
154
117
65
5
0
0
0
0
0
3
5
12
8
45
1
25
12
1
0
0
0
0
0
B
0
28
84
72
24
213
3
187
136
67
6
0
0
0
0
0
0
14
11
2
45
0
35
16
9
1
0
0
0
0
C
72 Hour*
3
25
98
71
18
210
3
169
123
58
3
0
0
0
0
0
2
8
8
1
40
0
29
20
11
2
0
0
0
0
D
0
15
42
37
9
111
0
89
62
27
0
0
0
0
0
0
0
2
4
1
20
0
12
8
3
1
0
0
0
0
A
0
20
47
38
4
121
0
93
84
23
0
0
0
0
0
0
0
2
5
2
19
0
17
5
5
3
0
0
0
0
B
0
17
42
38
9
117
0
89
64
31
13
0
0
0
0
0
0
2
4
1
23
0
12
8
3
1
0
0
0
0
A
0
21
48
38
4
126
0
93
89
27
17
0
0
0
0
0
0
2
5
4
21
0
17
5
7
3
0
0
0
0
B
72 Hour
APTS (0.25mL)
48 Hour
Replicate
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 2. Salad Dressing Results — Weissella viridescens
Low Level
Medium Level
16
57
266
146
NA
570
8
251
226
111
69
18
9
7
0
4
4
40
27
29
89
0
52
42
19
17
3
2
1
0
A
13
62
255
166
NA
513
8
266
219
120
73
17
10
9
0
3
4
40
28
22
86
1
47
50
23
14
6
2
2
0
B
16
57
270
151
NA
570
8
254
231
115
69
20
9
7
0
4
4
41
28
29
89
0
55
44
19
18
3
2
6
0
A
13
64
260
168
NA
513
8
270
226
126
73
21
10
11
0
3
4
44
31
24
86
2
49
51
23
17
7
2
3
0
B
72 Hour
APTS (1.0mL)
48 Hour
15
48
200
166
8
121
11
189
200
81
43
12
10
9
0
3
7
27
20
26
70
0
18
39
20
11
1
2
1
0
A
18
66
221
180
8
126
9
186
188
93
49
7
6
6
0
4
8
20
16
24
73
2
16
43
17
10
2
1
2
0
B
19
59
216
139
6
128
12
177
206
88
48
10
2
6
0
1
5
29
36
20
78
0
11
50
29
10
1
0
0
0
A
13
72
229
158
11
119
13
159
221
101
56
9
1
6
0
3
4
40
37
19
66
0
14
46
31
9
1
0
0
0
B
72 Hour
MRS (1.0mL)
48 Hour
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Caesar 2
LoFat Caesar 1
LoFat Caesar 2
Ranch 1
Ranch 2
LoFat Ranch 1
LoFat Ranch 2
Catalina 1
Catalina 2
Blue Cheese 1
Blue Cheese 2
Blue Cheese 3
Zesty Italian 1
Zesty Italian 2
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
1.4198
1.4198
0.3673
0.4355
0.9183
0.9183
1.1190
0.9183
1.1190
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
0.6696
1.4655
1.4655
0.7680
0.8375
0.8375
0.6696
0.3673
0.4355
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
0.4759
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
0.3673
Ref Mean
Method 1 — 0.5 x 2 Replicates
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
™
3M Petrifilm Aerobic
Count Plate Mean
™
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Comparison
Table 4. Salad Dressing T-Test Results
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Caesar 1
72 Hour
APTS Spread Plate
72 Hour 3M Petrifilm
Aerobic Count Plate
Lactobacillus fermentum
Salad Dressing
™
™
Table 3. Salad Dressing Gas Production Results
Low Inoculum
Medium Inoculum
Page 9
0.0010
0.0000
0.0075
0.0002
0.3442
0.0002
0.0001
0.0148
0.0010
0.2887
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
™
™
™
1.1571
0.8984
1.1571
0.8984
0.8984
0.4752
0.4128
0.4752
0.4128
0.4128
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
1.4717
1.4717
1.4020
1.4020
0.7657
0.8265
0.8265
0.6699
0.6699
0.4823
Ref Mean
Method 2 — Analysis of 4 Replicates
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Spread Plate
Weissella viridescens
3M Petrifilm Aerobic
Count Plate Mean
72 Hour 3M Petrifilm
Aerobic Count Plate
™
0.0004
0.0000
0.0159
0.0001
0.3911
0.0003
0.0001
0.0290
0.0003
0.4190
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
Page 10
6
7
3
3
4
7
22
41
Bean 1
Bean 2
Bean 3
Coleslaw 1
Coleslaw 2
Coleslaw 3
Mustard Potato 1
Mustard Potato 2
44
26
11
36
19
31
36
20
Macaroni 2
Macaroni 3
Bean 1
Bean 2
Bean 3
Coleslaw 1
Coleslaw 2
Coleslaw 3
* Acid zones
36
Macaroni 1
33
3
Macaroni 3
29
3
Macaroni 2
American Potato 3
5
Macaroni 1
American Potato 2
33
4
American Potato 3
36
3
American Potato 2
40
40
3
American Potato 1
Mustard Potato 3
6
3
Mustard Potato 3
American Potato 1
6
3
Mustard Potato 2
26
37
29
22
31
17
24
39
42
28
24
36
19
2
6
5
4
2
7
4
2
4
5
4
6
4
5
Mustard Potato 1
B
A
Dressing
22
18
26
24
30
21
20
36
40
26
31
27
26
30
26
1
3
6
4
7
3
3
11
4
6
8
7
4
2
7
C
24 Hour*
23
22
30
34
26
20
19
41
27
20
30
29
31
29
28
2
4
6
7
5
4
2
8
8
3
4
2
3
4
1
D
66
81
59
66
79
64
49
66
79
88
66
74
62
86
76
11
9
4
14
13
11
5
8
9
4
8
9
8
5
6
A
69
80
49
60
82
49
59
58
78
79
70
89
71
80
71
9
7
6
9
7
5
4
9
6
8
12
8
8
8
6
B
60
90
63
59
81
51
55
71
66
81
74
96
70
81
66
8
8
7
11
10
5
5
15
9
10
12
10
10
8
8
C
48 Hour*
61
77
66
71
76
54
63
70
69
80
70
90
78
66
70
10
7
8
12
15
9
7
11
9
8
8
7
9
9
7
D
67
81
59
66
82
65
49
67
79
88
66
77
62
86
76
11
9
4
14
13
11
6
8
9
4
8
9
8
6
6
A
70
80
52
61
82
49
60
59
78
80
70
91
71
82
71
10
7
7
9
7
5
5
9
6
8
12
11
8
8
8
B
61
90
63
60
81
54
56
73
66
81
74
96
70
81
69
10
8
8
11
10
5
5
15
9
11
13
10
10
8
8
C
Replicate
72 Hour*
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 5. RTE Salad Results — Lactobacillus fermentum
Low Level
Medium Level
64
77
66
72
77
55
63
70
69
81
72
90
78
70
71
10
7
8
12
17
9
8
12
10
8
8
7
9
9
7
D
A
177
182
179
236
216
224
230
504
196
257
224
287
285
294
210
18
18
21
26
18
25
30
56
17
12
22
36
19
19
18
B
201
195
210
178
191
201
232
497
219
229
263
267
259
291
226
28
21
19
32
19
31
27
46
25
25
17
29
32
19
21
A
209
206
221
208
201
226
242
539
223
266
269
297
288
303
217
22
19
28
30
19
27
31
63
24
19
24
39
20
20
20
B
182
205
190
245
223
242
238
521
198
237
232
275
273
297
237
29
22
22
34
21
32
30
55
26
29
18
30
37
21
27
72 Hour
APTS (1.0mL)
48 Hour
A
110
146
120
177
155
186
202
196
196
188
206
211
160
186
128
20
19
16
32
18
20
19
20
17
23
22
19
17
18
15
B
106
166
108
192
161
158
218
188
191
201
201
226
166
199
140
20
26
22
22
27
24
28
27
20
12
16
23
19
15
19
A
119
129
109
161
146
201
206
176
188
166
187
200
141
168
141
16
23
21
26
18
21
22
27
20
19
24
28
21
14
16
B
111
146
100
189
172
186
200
189
172
180
199
197
147
179
136
19
28
20
20
20
21
24
21
16
26
21
23
18
20
19
72 Hour
MRS (1.0mL)
48 Hour
Page 11
7
1
2
0
0
0
14
21
Bean 1
Bean 2
Bean 3
Coleslaw 1
Coleslaw 2
Coleslaw 3
Mustard Potato 1
Mustard Potato 2
* Acid zones
14
18
Bean 3
Coleslaw 3
16
Bean 2
6
18
Bean 1
11
13
Macaroni 3
Coleslaw 2
12
Macaroni 2
Coleslaw 1
7
Macaroni 1
13
0
Macaroni 3
20
1
Macaroni 2
American Potato 3
1
Macaroni 1
American Potato 2
22
1
American Potato 3
20
1
American Potato 2
21
19
2
American Potato 1
Mustard Potato 3
2
3
Mustard Potato 3
American Potato 1
4
2
Mustard Potato 2
14
17
3
20
13
19
15
16
12
17
19
16
16
0
2
0
1
1
1
1
1
2
1
4
2
3
3
Mustard Potato 1
B
A
Dressing
11
18
13
20
13
26
18
9
10
19
16
16
24
26
26
0
0
1
1
0
1
2
1
0
0
2
4
2
4
1
C
24 Hour*
14
16
6
25
16
19
22
17
9
16
19
26
22
19
20
0
0
0
1
0
2
3
1
1
3
5
3
1
1
2
D
19
13
6
19
21
29
23
20
26
29
36
30
49
41
48
4
1
0
4
4
8
0
1
1
2
3
4
5
5
3
A
21
24
6
27
29
33
29
26
29
36
38
33
56
41
32
0
2
0
4
7
4
4
3
3
1
4
2
7
5
5
B
21
30
13
29
33
32
34
30
19
35
41
38
50
40
45
0
0
1
6
3
2
4
2
2
1
6
5
7
5
2
C
48 Hour*
22
28
14
30
40
36
30
19
20
27
40
43
51
39
38
0
1
0
5
0
3
1
1
2
4
10
7
2
1
3
D
20
13
6
19
22
29
23
20
26
33
36
34
50
43
50
4
1
0
4
4
8
0
1
1
2
3
4
5
5
3
A
22
24
6
28
29
33
31
28
30
36
38
33
56
44
32
0
2
0
4
7
4
4
3
3
1
4
3
7
5
5
B
23
30
13
30
33
32
34
30
19
35
41
38
50
40
45
0
1
1
6
3
2
4
3
2
1
6
5
7
5
2
C
Replicate
72 Hour*
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 6. RTE Salad Results — Weissella viridescens
Low Level
Medium Level
22
28
16
32
41
36
32
19
21
27
40
43
51
39
39
0
1
0
5
0
3
1
1
2
4
10
8
2
1
3
D
27
97
20
204
107
143
46
67
55
170
118
124
161
135
64
1
8
3
26
11
20
5
3
4
13
12
14
17
16
8
A
30
83
23
185
114
161
36
78
66
151
122
109
158
153
77
4
8
2
22
10
13
5
4
2
14
13
14
23
12
7
B
A
35
106
21
200
107
152
53
67
55
170
118
124
181
148
64
2
8
3
26
14
23
5
3
4
13
12
14
17
16
13
8
B
38
97
26
191
114
161
39
81
56
151
122
109
158
153
77
5
8
2
22
10
13
5
4
2
14
19
15
25
12
72 Hour
APTS (1.0mL)
48 Hour
41
42
17
115
77
62
31
40
22
82
117
113
76
88
108
0
8
3
13
9
16
3
8
4
9
15
10
13
17
8
A
45
40
13
108
81
69
36
36
28
87
116
104
83
91
111
1
11
2
21
10
13
5
8
3
14
6
10
12
13
4
B
40
46
10
110
76
70
30
42
30
80
111
89
81
95
96
1
7
1
20
8
18
5
6
2
13
16
10
16
18
7
A
5
B
40
39
19
101
88
78
32
31
31
77
108
101
87
96
110
3
8
2
16
7
19
5
7
2
13
12
11
16
20
72 Hour
MRS (1.0mL)
48 Hour
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Mustard Potato 2
Mustard Potato 3
American Potato 1
American Potato 2
American Potato 3
Macaroni 1
Macaroni 2
Macaroni 3
Bean 1
Bean 2
Bean 3
Coleslaw 1
Positive
Coleslaw 3
Positive
1.9164
1.9515
1.9164
1.9515
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
1.9164
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
0.9229
0.9670
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
0.9670
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
0.9229
0.9229
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
1.9808
1.9965
2.1782
2.1782
2.1540
1.1028
1.0813
1.1783
1.1866
1.1523
Ref Mean
Method 1 — 0.5 x 2 Replicates
Comparison
Positive
Positive
3M™ Petrifilm™ Aerobic
Count Plate Mean
Table 8. RTE Salad T-Test Results
Positive
Coleslaw 2
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Lactobacillus fermentum
Mustard Potato 1
™
72 Hour 3M Petrifilm
Aerobic Count Plate
™
RTE Salad
Table 7. RTE Salad Gas Production Results
Low Inoculum
Medium Inoculum
Page 12
0.2831
0.0054
0.0000
0.0000
0.0000
0.0066
0.0058
0.0000
0.0000
0.0000
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
0.9479
1.9571
1.9499
1.9571
1.9499
1.9499
0.9558
0.9479
0.9558
0.9479
1.9886
1.9886
2.1753
2.1753
2.1557
1.0921
1.0921
1.1825
1.1825
1.1385
Ref Mean
Method 2 — Analysis of 4 Replicates
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Weissella viridescens
3M™ Petrifilm™ Aerobic
Count Plate Mean
™
72 Hour 3M Petrifilm
Aerobic Count Plate
™
0.1926
0.1109
0.0000
0.0000
0.0000
0.0002
0.0002
0.0000
0.0000
0.0000
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
Page 13
Natural Contamination
O/R Chicken 1
* Acid zones
Natural Contamination
Natural Contamination
Roast Beef 1
Roast Beef 2
Natural Contamination
Natural Contamination
Smoked Ham 1
Smoked Ham 2
Weissella
O/R Chicken 2
Weissella
Weissella
O/R Turkey 2
O/R Turkey 1
Lactobacillus
O/R Turkey 1
Lactobacillus
Natural Contamination
O/R Chicken 1
Lactobacillus
Natural Contamination
Roast Beef 2
O/R Turkey 2
Natural Contamination
Roast Beef 1
O/R Chicken 2
Natural Contamination
Natural Contamination
Smoked Ham 1
Weissella
O/R Chicken 2
Smoked Ham 2
Weissella
Weissella
O/R Turkey 1
O/R Turkey 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
11
0
0
0
0
0
Lactobacillus
Lactobacillus
O/R Turkey 2
O/R Chicken 2
0
Lactobacillus
O/R Turkey 1
A
Organism
Meat
Table 9. RTE Meat Results
Low Level
Medium Level
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
6
0
0
0
0
0
0
B
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
7
0
0
0
0
0
0
C
24 Hour*
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
5
0
0
0
0
0
0
D
60
66
39
66
0
21
21
11
10
18
15
6
10
6
6
11
6
5
3
0
3
1
A
50
69
45
82
0
17
20
14
11
22
21
7
11
5
9
6
9
7
6
1
0
0
B
46
81
51
77
0
17
15
10
13
24
20
7
8
3
11
6
11
8
4
0
2
0
C
48 Hour*
55
80
52
75
0
18
19
17
10
17
17
7
7
4
6
10
10
8
3
1
1
1
D
60
70
41
66
69
24
21
11
12
20
16
6
12
6
7
14
6
5
4
1
3
2
55
69
45
83
88
20
22
15
14
22
24
9
11
6
11
6
10
8
6
1
1
1
B
Replicate
A
47
83
53
78
89
17
18
12
15
24
20
7
9
5
11
8
13
9
5
0
3
1
C
72 Hour*
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
57
80
53
80
95
20
19
10
10
19
19
7
7
6
8
10
12
8
5
2
1
1
D
131
177
155
798
627
46
41
38
28
61
46
35
20
15
80
69
18
19
15
3
4
4
A
129
185
161
798
570
37
44
30
32
60
50
30
23
18
77
53
26
22
12
4
6
3
B
135
184
158
798
627
48
41
38
29
65
49
40
21
17
84
70
18
21
17
5
9
7
A
131
191
171
798
570
40
44
31
32
61
54
33
23
19
80
56
31
22
12
6
9
6
B
72 Hour
APTS (1.0mL)
48 Hour
136
135
130
120
342
41
30
26
26
54
46
25
28
15
17
35
15
11
15
7
6
8
A
126
139
121
112
399
40
29
24
26
51
39
20
35
17
17
32
14
13
11
4
5
7
B
72 Hour
MRS (1.0mL)
72 Hour 3M Petrifilm
Aerobic Count Plate
Positive
Positive
Positive
O/R Turkey 1
O/R Turkey 2
O/R Chicken 2
Positive
Positive
Positive
Roast Beef 2
O/R Chicken 1
1.5882
1.7758
1.5882
1.7758
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
1.5882
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
0.8874
0.9814
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
0.9814
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
0.8874
0.8874
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
1.8460
1.8460
2.0044
2.0044
1.9921
1.1144
1.1144
1.2937
1.2937
1.1959
Ref Mean
Method 1 — 0.5 x 2 Replicates
Comparison
Positive
3M™ Petrifilm™ Aerobic
Count Plate Mean
Table 11. RTE Meat T-Test Results
Positive
Positive
Roast Beef 1
Positive
Positive
Positive
Smoked Ham 1
Smoked Ham 2
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Lactobacillus fermentum
Natural Contamination
™
RTE Meat
™
RTE Meat
Table 10. RTE Meat Gas Production Results
Low Inoculum
Medium Inoculum
Page 14
0.1480
0.2886
0.0148
0.1158
0.1278
0.0017
0.0047
0.0008
0.0003
0.0015
P-Value
Positive
Positive
Positive
0.8646
1.8027
1.5815
1.8027
1.5815
1.5815
0.9832
0.8646
0.9832
0.8646
1.8382
1.8382
2.0082
2.0082
1.9963
1.1352
1.1352
1.2938
1.2938
1.2070
Ref Mean
Method 2 — Analysis of 4 Replicates
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Weissella viridescens
3M™ Petrifilm™ Aerobic
Count Plate Mean
™
72 Hour 3M Petrifilm
Aerobic Count Plate
™
0.3781
0.2952
0.0118
0.1077
0.1186
0.0274
0.0127
0.0003
0.0002
0.0003
P-Value
Positive
Positive
Positive
72 Hour
MRS
Page 15
NC
NC
Steak 1
Steak 2
0
0
0
0
0
0
0
0
0
0
0
0
0
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Ground Turkey 2
Chicken 1
Chicken 2
Ground Beef 1
Ground Beef 2
Steak 1
Steak 2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D
72 Hour 3M Petrifilm Aerobic Count Plate
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
C
Raw Meat
™
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
B
Ground Turkey 1
™
Table 13. Raw Meat Gas Production Results
* Acid zones
NC= Natural Contamination
TNTC= To Numerous to Count
NC
NC
Ground Beef 1
NC
Chicken 2
Ground Beef 2
NC
NC
Chicken 1
NC
Ground Turkey 1
Ground Turkey 2
NC
NC
Steak 1
Steak 2
NC
Ground Beef 2
0
NC
NC
Chicken 2
Chicken 1
Ground Beef 1
0
NC
NC
Ground Turkey 2
0
NC
Ground Turkey 1
A
Organism
24 Hour*
24
41
20
0
17
6
30
10
7
14
3
8
4
1
17
3
B
26
37
17
0
15
5
37
12
5
6
6
11
4
0
14
4
C
28
32
24
0
13
6
40
15
5
7
7
12
1
1
15
4
D
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
35
8
47
12
6
12
5
11
5
0
19
5
A
30
49
51
114
72 Hour APTS Pour Plate
Natural Contamination
27
46
11
0
17
7
41
10
5
9
4
9
5
0
13
5
A
48 Hour*
31
41
53
131
31
6
33
12
9
17
4
9
4
1
18
3
B
29
32
46
123
40
6
41
15
7
15
9
15
3
1
16
6
D
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour MRS
26
40
55
146
39
5
37
13
5
18
6
13
5
0
17
5
C
Replicate
72 Hour*
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Meat
Table 12. Raw Meat Results
Low Level
Medium Level
A
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
B
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
A
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
B
72 Hour
APTS (1.0mL)
48 Hour
A
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
B
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
A
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
B
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
TNTC
72 Hour
MRS (1.0mL)
48 Hour
0
Letheen
Letheen
Letheen
Letheen
Letheen
Swab 12
Swab 13
Swab 14
Swab 15
Swab 16
* Acid zones
Letheen
Swab 11
0
Letheen
Letheen
Swab 9
Letheen
Letheen
Swab 15
Swab 16
Swab 10
0
Letheen
Swab 14
0
0
0
0
0
0
0
0
0
0
0
Letheen
Letheen
Swab 12
0
0
Swab 13
Letheen
Swab 11
0
Letheen
Letheen
Swab 9
Swab 10
0
0
N Buffer
N Buffer
Swab 7
0
0
Swab 8
N Buffer
N Buffer
Swab 4
Swab 5
0
N Buffer
N Buffer
Swab 3
0
0
0
0
0
0
0
0
0
0
A
Swab 6
N Buffer
N Buffer
Swab 1
Swab 2
N Buffer
N Buffer
Swab 7
N Buffer
Swab 6
Swab 8
N Buffer
N Buffer
Swab 4
Swab 5
N Buffer
N Buffer
Swab 2
Swab 1
Swab 3
Diluent
N Buffer
Sample
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
B
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
C
24 Hour
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D
34
25
33
36
41
28
33
50
12
9
7
11
6
8
10
6
18
14
19
30
14
17
20
28
4
8
7
9
15
11
7
5
A
30
26
27
33
43
25
35
39
11
8
8
10
7
12
12
7
40
29
39
59
35
30
81
60
4
9
7
13
16
10
9
4
B
30
26
25
35
44
29
39
41
11
11
18
12
5
10
13
8
50
25
45
59
38
29
38
60
7
8
5
8
14
12
11
8
C
48 Hour*
39
30
26
32
40
30
36
44
9
10
18
10
5
16
9
11
53
25
37
63
30
40
39
67
7
8
6
10
13
15
13
6
D
34
25
33
36
41
28
33
50
12
9
8
11
6
9
10
6
37
28
38
60
28
33
40
56
5
8
7
10
15
11
7
5
A
30
26
27
33
43
25
34
38
11
8
7
10
7
12
13
7
40
29
39
59
36
30
41
60
4
6
7
13
16
11
9
5
B
30
26
25
35
44
29
38
41
11
10
8
15
6
10
13
10
50
25
45
59
37
28
38
59
7
8
5
8
15
12
11
8
C
Replicate
72 Hour*
39
30
26
32
40
30
36
44
9
10
10
10
6
16
9
11
53
25
37
63
32
40
39
67
7
7
6
11
13
15
13
6
D
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 14. Stainless Steel Environmental Results — Lactobacillus fermentum
Low Level
Medium Level
Low Level
Medium Level
Page 16
18
13
12
15
20
15
14
25
5
6
6
7
4
8
6
5
25
15
18
28
16
22
19
39
3
5
3
5
10
4
8
5
A
19
12
11
14
20
17
15
25
5
5
5
6
2
9
6
3
27
17
22
25
16
22
19
40
3
3
4
9
8
7
8
4
B
18
13
12
15
20
15
14
25
10
12
11
13
7
16
11
8
25
15
18
28
16
22
19
39
5
10
5
10
20
8
17
9
A
19
12
11
14
20
17
15
25
10
9
9
12
5
18
11
5
27
17
22
25
16
22
19
40
6
6
8
17
16
13
7
8
B
72 Hour
APTS (0.25mL)
48 Hour
A
56
66
40
58
89
69
59
76
8
8
9
16
7
13
12
7
98
70
75
106
49
81
66
122
4
8
7
11
11
15
6
11
66
64
37
63
77
71
52
71
7
8
7
16
8
13
9
10
96
63
79
99
55
77
81
111
5
8
7
11
11
16
6
5
B
56
66
40
58
89
69
59
76
16
17
18
32
15
27
24
13
98
70
75
106
49
81
66
122
8
17
15
22
23
29
22
22
A
66
64
37
63
77
71
52
71
13
17
14
31
17
25
19
20
96
63
79
99
55
77
81
111
10
16
13
21
22
32
24
11
B
72 Hour
APTS (1.0mL)
48 Hour
A
66
72
77
81
80
56
48
66
15
22
30
33
18
26
19
14
100
66
78
95
50
91
90
100
12
18
14
30
20
27
21
15
B
59
70
76
90
66
66
49
67
16
27
19
30
22
22
20
20
92
75
77
109
51
77
92
118
11
20
14
32
19
25
22
17
71
69
55
59
69
72
50
72
19
24
21
34
31
25
16
15
88
60
58
91
55
72
90
107
16
18
11
19
38
27
31
22
A
70
55
50
73
53
73
37
75
20
23
26
33
24
30
11
15
77
72
71
99
70
72
81
100
19
19
13
16
29
25
40
17
B
72 Hour
MRS (1.0mL)
48 Hour
0
Letheen
Letheen
Letheen
Letheen
Letheen
Swab 12
Swab 13
Swab 14
Swab 15
Swab 16
* Acid zones
Letheen
Swab 11
0
Letheen
Letheen
Swab 9
Letheen
Letheen
Swab 15
Swab 16
Swab 10
0
Letheen
Swab 14
0
0
0
0
0
0
0
0
0
0
0
Letheen
Letheen
Swab 12
0
0
Swab 13
Letheen
Swab 11
0
Letheen
Letheen
Swab 9
Swab 10
0
0
N Buffer
N Buffer
Swab 7
0
0
Swab 8
N Buffer
N Buffer
Swab 4
Swab 5
0
N Buffer
N Buffer
Swab 3
0
0
0
0
0
0
0
0
0
0
A
Swab 6
N Buffer
N Buffer
Swab 1
Swab 2
N Buffer
N Buffer
Swab 7
N Buffer
Swab 6
Swab 8
N Buffer
N Buffer
Swab 4
Swab 5
N Buffer
N Buffer
Swab 2
Swab 1
Swab 3
Diluent
N Buffer
Sample
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
B
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
C
24 Hour
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
D
1
2
3
2
0
0
2
2
0
1
0
0
0
0
0
0
3
15
11
9
4
13
9
0
2
1
0
1
0
3
4
1
A
0
0
0
1
0
14
8
5
0
14
4
7
3
1
3
0
1
9
7
12
8
10
10
8
8
0
0
0
0
0
4
2
B
0
3
7
3
11
12
3
5
3
10
5
10
6
2
3
8
3
11
9
13
7
15
7
20
6
1
1
0
1
1
1
1
C
48 Hour*
4
1
11
2
3
16
4
4
2
7
4
10
6
4
3
2
2
13
16
13
3
21
7
17
6
0
0
0
1
1
2
3
D
1
4
5
2
5
3
3
3
0
2
0
3
1
0
1
0
3
19
14
10
4
15
11
0
4
1
0
1
0
3
5
1
A
2
2
4
1
0
17
10
7
0
18
8
12
5
1
4
1
2
10
10
13
8
16
10
12
10
1
0
0
0
0
4
2
B
1
4
9
3
14
13
5
5
4
15
5
13
13
4
3
9
5
14
13
15
7
22
8
29
8
1
1
0
2
1
1
3
C
Replicate
72 Hour*
5
2
11
2
5
19
6
4
2
11
8
14
9
5
4
3
2
13
16
14
3
21
8
22
8
0
1
0
1
3
2
3
D
Aerobic Procedure for Lactic Acid Bacteria with 3M™ Petrifilm™ Aerobic Count Plates (0.5mL)
Table 15. Stainless Steel Environmental Results — Weissella viridescens
Low Level
Medium Level
Low Level
Medium Level
Page 17
1
0
0
0
3
5
1
1
0
5
0
3
1
1
2
1
0
2
1
2
3
8
0
6
1
0
1
3
0
0
0
1
A
1
1
0
0
4
4
1
3
0
5
1
3
0
1
0
2
0
4
4
5
6
8
0
6
1
1
2
3
0
0
0
1
B
2
0
0
1
3
5
1
1
2
5
0
3
1
1
2
1
0
6
1
2
4
8
0
16
1
0
1
3
0
0
0
1
A
3
1
0
0
4
4
2
3
0
5
2
5
0
1
0
3
11
4
4
6
6
8
0
16
3
1
2
3
2
0
0
2
B
72 Hour
APTS (0.25mL)
48 Hour
6
13
5
5
19
17
11
8
0
21
18
30
17
13
13
11
9
24
17
21
10
26
23
49
8
26
11
10
12
4
5
5
A
B
8
12
15
4
18
20
6
10
8
22
15
31
25
7
9
11
5
17
9
28
19
43
26
58
5
22
13
4
11
7
6
10
12
13
5
5
19
17
11
8
4
24
18
32
17
13
13
11
9
24
17
21
11
26
23
49
8
26
11
10
12
5
5
5
A
8
12
15
4
19
20
6
10
8
23
16
31
25
7
9
13
5
17
9
29
19
43
27
58
5
22
13
4
12
7
6
10
B
72 Hour
APTS (1.0mL)
48 Hour
6
10
4
9
11
25
15
10
5
21
17
26
19
21
11
16
14
28
22
33
14
35
22
31
6
17
11
6
15
8
6
7
A
6
6
6
7
7
14
8
13
9
24
18
19
21
20
11
14
13
31
21
31
22
27
17
34
4
21
11
6
13
11
9
8
B
2
12
12
3
12
47
15
16
4
22
17
31
19
14
7
11
16
28
23
33
15
35
31
31
4
23
10
11
16
9
10
12
A
13
21
13
7
28
33
10
13
15
32
24
30
22
15
8
9
15
34
28
31
27
27
20
59
9
19
12
10
17
12
19
13
B
72 Hour
MRS (1.0mL)
48 Hour
72 Hour 3M Petrifilm
Aerobic Count Plate
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Environmentals
1 D/E Neutralizing Broth
2 D/E Neutralizing Broth
3 D/E Neutralizing Broth
4 D/E Neutralizing Broth
5 D/E Neutralizing Broth
6 D/E Neutralizing Broth
7 D/E Neutralizing Broth
8 D/E Neutralizing Broth
1 Letheen Broth
Positive
8 Letheen Broth
1.0293
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
1.5017
0.9812
0.9812
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
1.0293
1.0293
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
0.9812
0.9812
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
1.0293
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour MRS
72 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
1.5133
0.9812
48 hour 3M Petrifilm Aerobic Count Plate vs. 72 hour APTS
1.5245
1.5245
1.491
1.2553
1.2553
1.1636
1.1636
0.9772
0.9812
48 hour 3M Petrifilm Aerobic Count Plate vs. 48 hour APTS
Ref Mean
Method 1 — 0.5 x 2 Replicates
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
3M Petrifilm Aerobic
Count Plate Mean
™
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
Comparison
™
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
Lactobacillus fermentum
72 Hour
APTS Spread Plate
Table 17. Stainless Steel Environmental T-Test Results
Positive
Positive
6 Letheen Broth
7 Letheen Broth
Positive
Positive
4 Letheen Broth
3 Letheen Broth
5 Letheen Broth
Positive
Positive
2 Letheen Broth
™
™
Table 16. Stainless Steel Environmental Gas Production Results
Low Inoculum
Medium Inoculum
Page 18
0.0000
0.0000
0.0000
0.0000
0.0000
0.0012
0.0003
0.0453
0.0057
0.962
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
™
™
0.9550
0.8932
0.9550
0.8932
0.8932
0.9550
0.8932
0.9550
0.8932
0.8932
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Pour Plate
1.5503
1.5503
1.5028
1.5028
1.4966
1.2312
1.2312
1.1573
1.1573
0.9816
Ref Mean
Method 2 — Analysis of 4 Replicates
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
APTS Spread Plate
Weissella viridescens
3M Petrifilm Aerobic
Count Plate Mean
™
72 Hour 3M Petrifilm
Aerobic Count Plate
™
0.0000
0.0000
0.0000
0.0000
0.0000
0.0001
0.0000
0.0023
0.0005
0.3253
P-Value
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
Positive
72 Hour
MRS
Page 19
70-2009-9494-8
3M and Petrifilm are trademarks of 3M.
Used under license in Canada.