Collecting data for modeling:
Product heat penetration,
equipment temperatures,
and residence time
Presentation to the
GMA Science Forum
April 4, 2012
David Anderson
Food Safety Manager
Del Monte Foods Company
Pittsburgh PA
V1
Discussion points
A. Introduction
B. Methods to validate processes
C. Validation tasks
D. Further information
E. References
A. Introduction: Examples of processes
Milk, Eggs: Pasteurize (wet)
Almonds: Water blanch
Hot, humid air
Steam
Kibbles: PreCondition
Treats:
Extrude
Bones:
Bake
Jerky:
Steam
Dry
Dry Roast
Oil Roast
Extrude
Cool
Dry
Dry
Dry
Cool
Cool
Cool
Dry
Cool
B. Methods to validate
processes
Methods to validate processes
Codex (CAC/GL 69-2008) and Scott (2005):
• Use scientifically valid data
• Conduct experiments
(microbiological tests, and
measures of the system & product)
• Use mathematical modeling
Σ[(10
(T – Tref)/z
)Δt]/D
Experiments
• Tests of the system
• Temperature mapping; Heat transfer distribution
• Retention time
• Other required process conditions (e.g. rel. humidity)
• Tests of the product
• Heat penetration studies
• Analyses (e.g., moisture/aw, preservative level)
• Microbiological tests
• Thermal death time studies
• Count-reduction tests in lab or in process
• End-point lethality (presence/absence) tests
Temperature mapping
Continuous baking oven:
Entry
Datalogger spans the
width of the belt
Exit
Temperature mapping
To confirm minimum temperatures; adjust the process…
Continuous baking oven (from top, looking down):
Heat Transfer Distribution
To confirm uniform heat transfer & adjust the process…
Moist heat
(retorts)
Lowmoisture
Material
Reference
Lexan® blocks
(Campbell and
Ramaswamy, 1992)
Aluminum or steel bricks
(Tung and others, 1984)
Silicone food simulants
(Smout and others, 1998)
Product-filled containers
(IFTPS, 2008)
5% Bentonite-filled
containers, or other
material of known heating
(FDA, 2011c)
Aluminum
almond
ABC, 2007d
(Photo from Harris, 2009)
Product heat penetration
To understand heating rates & model the process…
Example, pet treats:
Temperature
probes and
location in
product:
Product entry
into the oven:
Heat penetration
Wireless datalogger examples
DataTrace MPIIITM
and MadgeTech
Temperature
dataloggers, with protective
insulation for high
temperatures.
Scorpion Data Logging System
for ovens (Temperature, air
velocity, heat flux, humidity).
Examples of equipment suppliers
Manufacturer
DataTrace MPIII TM (Mesa Labs)
Dickson
Ecklund Harrison
Ellab Tracksense® Pro
MadgeTech, Inc.
Omega Engineering
Scorpion Systems
Super M.O.L.E.®
TechniCAL, Inc.
ThermoLog TM
TMI
Web address
www.mesalabs.com
www.dicksondata.com
www.ecklund-harrison.com
www.ellab.com
www.madgetech.com
www.omega.com
www.readingbakery.com
www.ecd.com
www.tcal.com
www.c-p-e.be
www.tmi-orion.com
(Not an endorsement of any supplier. Exclusions are unintended.)
Retention time studies
To demonstrate retention,
prepare for lab simulations;
model the process…
Options:
- Mark product or belt, use a stopwatch
- Analytes (e.g. salt in product, in preconditioner
or extruder)
- Note that some particles may travel faster than
the mass average in dryers with a tumble
C. Validation tasks
1. The source document describes a
scheduled thermal process…
Example 1:“Guidelines for Validation
of Blanching Processes” (ABC, 2007c)
“Guidelines for Validation
of Oil Roasting Processes” (ABC, 2007e)
• (ABC commissioned the TDT tests.)
• Measure uniformity of heating medium
temperature (e.g., a “temperature distribution” test).
• Measure residence time in equipment.
• ABC requires three validation runs.
• Control incoming, cold almond temperature and
other critical factors in production.
1. The source document describes a
scheduled thermal process…
Example 2:“Guidelines for Validation
of Dry Roasting Processes” (ABC, 2007d)
• ABC commissioned TDT tests.
• Identify the coldest spot or path for each roasting
line (e.g., a “temperature distribution” test).
• Use an aluminum almond, or similar device (e.g.,
a “heat transfer distribution” test).
• Measure residence time and temperatures
achieved during “worst case” conditions.
• ABC requires three validation runs.
• Control, monitor, verify CCPs in process.
1. The source document describes a
scheduled thermal process…
Example 3:“Appendix A, Compliance Guidelines … for
Certain Meat And Poultry Products” (FSIS, 1999)
• Temperature must be maintained in all parts of
each piece of meat for the required time
(e.g., a “heat penetration” test)
• 90% relative humidity is maintained during
processing.
• Control, monitor, verify CCPs in process.
2. The source document describes
D- and z-values…
• (TDT tests were conducted by the source.)
• Justify ‘substantial similarity’ of the product and
process to the source data.
• Obtain temperature distribution and/or
heat transfer distribution data from the process.
• Collect heat penetration data for the product
• Model the process for cumulative log reduction.
• General method models, Weibull model
• Consult your friendly neighborhood statistician!
• Control, monitor, verify CCPs in process.
D. Further Information
E. References
Validation guidance
• Guideline for the Validation of Food Safety Control
Measures (CAC/GL 69-2008) (Codex)
• ICMSF Microorganisms in Foods 8:
Use of Data for Assessing Process Control and
Product Acceptance (ICMSF, 2011)
• Validating the Reduction of Salmonella and Other
Pathogens in Heat Processed Low-Moisture
Foods. (Anderson and Lucore, April 2012)
http://community.pmmi.org/Alliance/Home/
References
ABC (Almond Board of California), 2007a. Considerations for Proprietary
Processes for Almond Pasteurization and Treatment, v1.0, April 13, 2007.
Almond Board of California, Modesto, CA. www.almondboard.com
ABC, 2007b. Guidelines for Process Validation Using Enterococcus faecium
NRRL B-2354, v1.2, October 2007. Almond Board of California, Modesto,
CA. www.almondboard.com
ABC, 2007c. Guidelines for Validation of Blanching Processes, v1.0, April 13,
2007. Almond Board of California, Modesto, CA. www.almondboard.com
ABC, 2007d. Guidelines for Validation of Dry Roasting Processes, October 2007.
Almond Board of California, Modesto, CA. www.almondboard.com
ABC, 2007e. Guidelines for Validation of Oil Roasting Processes, v1.0, April 13,
2007. Almond Board of California, Modesto, CA. www.almondboard.com
ABC, 2007f. Guidelines for Validation of Propylene Oxide Pasteurization, v3.0,
October 1, 2008. Almond Board of California, Modesto, CA.
www.almondboard.com
ABC, 2007g. Guidelines for Validation of Propylene Oxide Treatment for In-shell
Almonds, v2.0, October 1, 2008. Almond Board of California, Modesto, CA.
www.almondboard.com
References
ABC, 2007h. Pasteurization Treatments. December 2007. Almond Board of
California, Modesto, CA. www.almondboard.com
Anderson, D. G. and L. A. Lucore. 2012. Validating the Reduction of Salmonella
and Other Pathogens in Heat Processed Low-Moisture Foods. Alliance for
Innovation & Operational Excellence, Alexandria, VA. Published online at
http://community.pmmi.org/Alliance/Home/
ASTA (American Spice Trade Association), 2011. Clean, Safe SPICES:
Guidance from the American Spice Trade Association., 2025 M Street, NW,
Suite 800, Washingt5on, DC 20036. www.astaspice.org
Campbell, S. and H.S. Ramaswamy. 1992. Distribution of heat transfer rate and
lethality in a single basket water cascade retort. J. Food Process
Engineering. 15:31-48.
Center for Meat Process Validation, 2012. www.meathaccp.wisc.edu. Accessed
February 6, 2012.
Codex (Codex Alimentarius Commission), 2008. Guideline for the Validation of
Food Safety Control Measures (CAC/GL 69-2008). Joint FAO/WHO Food
Standards Program, FAO, Rome, Italy. www.codexalimentarius.net
References
FDA (Food and Drug Administration). 2011. Processing in Steam-Air Retorts (Retort
Survey). FDA Inspection Form FDA 3511h (1/11).
FSIS (U.S. Department of Agriculture - Food Safety Inspection Service), 1999.
Appendix A. Compliance guidelines for meeting lethality performance
standards for certain meat and poultry products. Available at
http://www.fsis.usda.gov/OPPDE/rdad/FRPubs/95-033F/95033F_Appendix%20A.htm . Accessed October 26, 2011
Harris, L. J., 2009. Process Validation for Low-Water Activity Foods. Presentation
for IAFP: Salmonella in Peanut Products. Found at
http://www.foodprotection.org/files/rr_presentations/RR_07.pdf
ICMSF (International Commission on Microbiological Specifications for Foods),
2011a. Microorganisms in Foods 8: Use of Data for Assessing Process
Control and Product Acceptance. Katherine M. J. Swanson, ed. chair. New
York: Springer Science+Business Media, LLC.
IFTPS, 2008. Temperature and Heat Transfer Distribution Guidelines for Processing
in Batch Agitating Retorts. From www.iftps.org, accessed February 13, 2012.
References
NACMCF (National Advisory Committee on Microbiological Criteria for Foods),
2006. Requisite Scientific Parameters for Establishing the Equivalence of
Alternative Methods of Pasteurization. J. Food Prot. 69:1190-1216.
NACMCF. 2010. Parameters for Determining Inoculated Pack/Challenge Study
Protocols. J. Food Prot. 73:140-202.
Scott, V. N.. 2005. How does industry validate elements of HACCP plans? Food
Control. 16:497-503.
Smout, C., A. Van Loey, M. Hendrickx. 1998. Heat Distribution in Industrial-scale
Water Cascading (Rotary) Retort. J. Food Sci. 63:882-886.
Tung, M. A., H. S. Ramaswamy, T. Smith and R. Stark. 1984. Surface heat transfer
coefficients for steam/air mixtures in two pilot scale retorts. J. Food Sci.
49:939-943.
Thank You
David Anderson
Food Safety Manager
Del Monte Foods Company
Pittsburgh PA