Microbiologist Benne Marmer
(left) and technician Tod Stewart
use computer-assisted laboratory
methods to record growth of
bacteria on ready-to-eat meat
products. This information is
analyzed in ComBase and then
converted to a model in the
ARS Pathogen Modeling Program
A new Agricultural
Research Service initiative will help facilitate research cooperation
among scientists studying a key food safety issuehow pathogenic
bacteria respond to different environmental conditions in food.
Scientists in the Eastern Regional Research Center's (ERRC)
Microbial Food Safety Research Unit in Wyndmoor, Pennsylvania, and the
United Kingdom's Institute of Food Research (IFR) have formed the world's
largest online database of predictive microbiology information. Predictive
microbiology is a growing field that estimates behavior of microorganisms
in response to environmental conditions, including food production and
processing operations from the farm to the table. The database, called
ComBase, is designed to help make risk assessments and model development
easier. It was released at the fourth International Predictive Modeling
in Foods Conference in June 2003 and can be found on the World Wide
Web at wyndmoor.arserrc.gov/combase.
For more than 15 years, ERRC has developed mathematical
models of the behavior of bacterial pathogens in food. In February 2002,
ERRC established the Center of Excellence in Microbial Modeling and
Informatics (CEMMI) to help generate interest in forming partnerships
that advance use of predictive models of microorganisms in food. This
"virtual laboratory" can be found at www.arserrc.gov/cemmi.
CEMMI's objective is to link the expertise of its members
to researchers in the food industry, government, and academia. According
to coordinator Mark L. Tamplin, the center hopes to improve the way
predictive models are developed and then applied to various food-processing
situations, while ensuring that users properly interpret results. Predictive
microbiology can also benefit the risk-assessment community by solving
gaps in research data and enhancing uniformity in experimental designs,
ERRC's Pathogen Modeling Program software, a research
and instructional tool for estimating the effects of multiple variables
on growth, inactivation, or survival of foodborne pathogens, has been
available for download since 2002 at www.arserrc.gov/mfs/pathogen.htm.
That program and the United Kingdom's Food MicroModel, produced by IFR
and the Foods Standards Agency, are both major software packages used
to describe bacterial responses to food environments. By combining their
efforts and using ComBase to organize the thousands of existing data
sets in the hands of scientists and in the literature, ARS and IFR have
expanded the uses for this vast amount of information.
ComBase, a CEMMI project, already contains around 25,000
growth and survival data set records. The software lets scientists simulate
a food environment by entering datasuch as temperature, acidity,
and available waterand then retrieves all records that match those
search criteria. Tamplin says microbiologists in academia, government,
and industry are submitting data to ComBase, thus eliminating unnecessary
repetition of experiments among laboratories, improving models, and
standardizing data sources. More than 1,000 people accessed ComBase
data in the first 4 months following its launch. Tamplin says the ultimate
success of ComBase relies on collaborators' willingness to deposit more
"Development of models depends on available data,"
he says. "We're appealing to professional journals to ask authors
to submit all their raw data with their articles, much as they already
do for papers about genomic sequences. This would help keep the database
timely and offer users the most reliable information."By
Agricultural Research Service Information Staff.
This research is part of Food Safety (Animal and Plant
Products), an ARS National Program (#108) described on the World Wide
Web at www.nps.ars.usda.gov.
Tamplin is with the USDA-ARS Microbial
Food Safety Research Unit, Eastern Regional Research Center, 600
East Mermaid Lane, Wyndmoor, PA 19038; phone (215) 836-3794, fax (215)
"New Database Helps Monitor Food Pathogens" was published
in the February
2004 issue of Agricultural Research magazine.