U.S. Food & Drug Administration
Center for Food Safety & Applied Nutrition
FISH AND FISHERIES PRODUCTS
HAZARDS AND CONTROLS GUIDANCE:

Third Edition June 2001

APPENDIX 4

Bacterial Pathogen Growth and Inactivation

(Return to table of contents.)

This appendix contains information on the growth and inactivation of bacterial pathogens.

Table #A-1 contains information on: the minimum water activity (aw), acidity (pH), and temperature; the maximum, pH, water phase salt, and temperature; and oxygen requirements that will sustain growth for the bacterial pathogens that are of greatest concern in seafood processing. Data shown are the minimum or maximum values, the extreme limits reported among the references cited. These values may not apply to your processing conditions.

Table #A-2 contains information on maximum, cumulative time/internal temperature combinations for exposure of fish and fishery products that, under ordinary circumstances, will be safe for the bacterial pathogens that are of greatest concern in seafood processing. These maximum, cumulative exposure times are derived from published scientific information. Because the nature of bacterial growth is logarithmic, linear interpolation using the time/temperature guidance is not appropriate.

In summary, the table indicates that:

It is not possible to furnish recommendations for each pathogen, process, type of seafood, and temperature or combination of temperatures. Programmable models to predict growth rates for certain pathogens associated with various foods under differing conditions have been developed by the U.S. Department of Agriculture ("Pathogen Modeling Program" [PMP]) and the United Kingdom ("Food MicroModel" [FMM]). These programs can provide growth curves for selected pathogens. You indicate the conditions, such as pH, temperature, and salt concentration that you are interested in and the models provide pathogen growth predictions (e.g., growth curve, time of doubling, time of lag phase, generation time). FDA does not endorse or require the use of such modelling programs, but recognizes that the predictive growth information they provide may be of assistance to some processors. However, you are cautioned that significant deviations between actual microbiological data in specific products and the predictions do occur, including those for the lag phase of growth. Therefore, you should validate the time-temperature limits derived from such predictive models.

Table #A-3 contains information on the destruction of Listeria monocytogenes. Lethal rate, as used in this table, is the relative lethality of one minute at the designated internal product temperature as compared to the lethality of one minute at the reference internal product temperature of 158°F (70°C) (i.e. z = 13.5°F [7.5°C]). For example, one minute at 145°F (63°C) is 0.117 times as lethal as one minute at 158°F (70°C). The times provided are the length of time at the designated internal product temperature necessary to deliver a 6D process for L. monocytogenes. The length of time at a particular internal product temperature needed to accomplish a six logarithm reduction in the number of L. monocytogenes (6D) is, in part, dependent upon the food in which it is being heated. The values in the table are generally conservative and apply to all foods. You may be able to establish a shorter process time for your food by conducting scientific thermal death time studies. Additionally, lower degrees of destruction may be acceptable in your food if supported by a scientific study of the normal innoculum in the food.

Table #A-4 contains information on the destruction of Clostridium botulinum type B (the most heat resistant form of nonproteolytic Clostridium botulinum). Lethal rate, as used in this table, is the relative lethality of one minute at the designated internal product temperature as compared to the lethality of one minute at the reference product internal temperature of 194°F (90°C) (i.e. for temperatures less than 194°F [90°C] z = 12.6°F [7.0°C] ; for temperatures above 194°F [90°C] z = 18°F [10°C];). The times provided are the length of time at the designated internal product temperature necessary to deliver a 6D process for C. botulinum. The values in the table are generally conservative. However, they may not be sufficient for the destruction of nonproteolytic C. botulinum in dungeness crabmeat, because of the potential protective effect of lysozyme. You may be able to establish a shorter process time for your food by conducting scientific thermal death time studies. Additionally, lower degrees of destruction may be acceptable in your food if supported by a scientific study of the normal innoculum in the food.

Table A-1

Limiting Conditions for Pathogen Growth

Pathogen min. aw
(using salt)
min. pH max. pH max. % water phase salt min. temp. max. temp. oxygen requirement
Bacillus Cereus .92 4.3 9.3 10 39.2°F
4°C
131°F****
55°C
aerobe
Campylobacter jejuni .987 4.9 9.5 1.5 86°F
30°C
113°F
45°C
micro-
aerophilic*
Clostridium botulinum,
type A, and proteolytic B and F
.935 4.6 9 10 50°F
10°C
118.4°F
48°C
anaerobe**
Clostridium botulinum,
type E, and nonproteolytic B and F
.97 5 9 5 37.9°F
3.3°C
113°F
45°C
anaerobe**
Clostridium perfringens .93 5 9 7 50°F
10°C
125.6°F
52°C
anaerobe**
pathogenic strains of
Escherichia coli
.95 4 9 6.5 43.7°F
6.5°C
120.9°F
49.4°C
facultative
anaerobe***
Listeria monocytogenes .92 4.4 9.4 10 31.3°F
-0.4°C
113°F
45°C
facultative
anaerobe***
Salmonella spp. .94 3.7 9.5 8 41.4°F
5.2°C
115.2°F
46.2°C
facultative
anaerobe***
Shigella spp. .96 4.8 9.3 5.2 43°F
6.1°C
116.8°F
47.1°C
facultative
anaerobe***
Staphylococcus aureus- growth .83 4 10 20 44.6°F
7°C
122°F
50°C
facultative
anaerobe***
Staphylococcus aureus- toxin .85 4 9.8 10 50°F
10°C
118°F
48°C
Vibrio cholerae .97 5 10 6 50°F
10°C
109.4°F
43°C
facultative
anaerobe***
Vibrio parahaemolyticus .94 4.8 11 10 41°F
5°C
113.5°F
45.3°C
facultative
anaerobe***
Vibrio vulnificus .96 5 10 5 46.4°F
8°C
109.4°F
43°C
facultative
anaerobe***
Yersinia enterocolitica .945 4.2 10 7 29.7°F
-1.3°C
107.6°F
42°C
facultative
anaerobe***
* requires limited levels of oxygen   ** requires the absence of oxygen   *** grows either with or without oxygen.   **** growth significantly delayed (>24 hr.) at 131°F (55°C)

Table A-2

Time/Temperature Guidance for
Controlling Pathogen Growth and Toxin Formation in Seafoods

Potentially Hazardous Condition Product Temperature Maximum Cumulative Exposure Time
Growth and toxin formation by Bacillus cereus 39.2-43°F (4-6°C)
44-50°F (7-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
5 days
17 hours*
6 hours*
3 hours
Growth of Campylobacter jejuni 86-93°F (30-34°C)
Above 93°F (above 34°C)
48 hours
12 hours
Germination, growth, and toxin formation by Clostridium botulinum type A, and proteolytic B and F 50-70°F (10-21°C)
Above 70°F (above 21°C)
11 hours
2 hours
Germination, growth, and toxin formation by Clostridium botulinum type E, and nonproteolytic B and F 37.9-41°F (3.3-5°C)
42-50°F (6-10 °C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
7 days
>2 days
11 hours
6 hours
Growth of Clostridium perfringens 50-54°F (10-12°C)
55-57°F (13-14 °C)
58-70°F (15-21°C)
Above 70°F (above 21°C)
21 days
1 day
6 hours*
2 hours*
Growth of pathogenic strains of Escherichia coli 44.6-50°F (7-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
14 days
6 hours
3 hours
Growth of Listeria monocytogenes 31.3-41°F (-0.4-5°C)
42-50°F (6-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
7 days
2 days
12 hours*
3 hours*
Growth of Salmonella species 41.4-50°F (5.2-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
14 days
6 hours
3 hours
Growth of Shigella species 43-50°F (6.1-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
14 days*
12 hours*
3 hours*
Growth and toxin formation by Staphylococcus aureus 44.6-50°F (7-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
14 days
12 hours*
3 hours
Growth of Vibrio cholerae 50°F (10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
21 days
6 hours*
2 hours*
Growth of Vibrio parahaemolyticus 41-50°F (5-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
21 days
6 hours*
2 hours*
Growth of Vibrio vulnificus 46.4-50°F (8-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
21 days
6 hours
2 hours
Growth of Yersinia enterocolitica 29.7-50°F (-1.3-10°C)
51-70°F (11-21°C)
Above 70°F (above 21°C)
1 days
6 hours
2.5 hours
* Additional data needed.

Table A-3
Inactivation of Listeria monocytogenes

Internal Product Temperature (°F) Internal Product Temperature (°C) Lethal Rate Time for 6D Process (minutes)
145 63 0.117 17.0
147 64 0.158 12.7
149 65 0.215 9.3
151 66 0.293 6.8
153 67 0.398 5.0
154 68 0.541 3.7
156 69 0.736 2.7
158 70 1.000 2.0
160 71 1.359 1.5
162 72 1.848 1.0
163 73 2.512 0.8
165 74 3.415 0.6
167 75 4.642 0.4
169 76 6.310 0.3
171 77 8.577 0.2
172 78 11.659 0.2
174 79 15.849 0.1
176 80 21.544 0.09
178 81 29.286 0.07
180 82 39.810 0.05
182 83 54.116 0.03
183 84 73.564 0.03
185 85 100.000 0.02
Note: z = 13.5°F (7.5°C)

Table A-4
Inactivation of nonproteoteolytic Clostridinum botulinum type B

Internal Product Temperature (°F) Internal Product Temperature (°C) Lethal Rate* Time for 6D Process (minutes)
185 85 0.193 51.8
187 86 0.270 37.0
189 87 0.370 27.0
190 88 0.520 19.2
192 89 0.720 13.9
194 90 1.000 10.0
196 91 1.260 7.9
198 92 1.600 6.3
199 93 2.000 5.0
201 94 2.510 4.0
203 95 3.160 3.2
205 96 3.980 2.5
207 97 5.010 2.0
208 98 6.310 1.6
210 99 7.940 1.3
212 100 10.000 1.0
Note: for temperatures less than 194°F (90°C) z = 12.6°F (7.0°C); for temperatures above 194°F (90°C) z = 18°F (10°C).

*Note: these lethal rates and process times may not be sufficient for the destruction of nonproteolytic C. botulinum in dungeness crabmeat, because of the potential that substances that may be naturally present, such as lysozyme, may enable the pathogen to more easily recover from heat damage.

 



See also:

FDA Seafood List

Foodborne Pathogenic Microorganisms and Natural Toxins Handbook (Bad Bug Book)

Seafood Information and Resources


Seafood HACCP   |   Fish & Fisheries Products Hazards & Controls Guidance: 3rd Edition (2001)


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