A Risk Assessment for C. perfringens in RTE and Partially Cooked Meat and Poultry Products
A Risk Assessment for Clostridium perfringens in Ready-to-Eat and Partially
Cooked Meat and Poultry Products
Executive Summary
September 2005
The United States Department of Agriculture (USDA) Food Safety and Inspection
Service (FSIS) conducted a quantitative risk assessment of Clostridium perfringens (C.
perfringens) in ready-to-eat (RTE) and partially cooked meat and poultry products. The
purpose of the risk assessment was twofold: 1) evaluate the public health impact of
changing the allowed maximal growth of C. perfringens during manufacturing
stabilization (cooling after the cooking step) of RTE and partially cooked meat and
poultry products; and 2) examine whether steps taken to limit the growth of C.
perfringens occurring in RTE and partially cooked foods would also be adequate to
protect against growth of Clostridium botulinum.
Public Health Regulatory Context
The bacterium C. perfringens grows well on meat and poultry products in the absence of
oxygen, and grows best at relatively high temperatures. Since C. perfringens is
ubiquitous in the environment, sources of raw meat1 are occasionally contaminated with
this organism, either in the form of vegetative cells or as spores. Vegetative cells are
destroyed during heating in the production of RTE foods, though may survive the
incomplete cooking used to prepare partially cooked foods. Spores, on the other hand,
are not destroyed by heat and other processes applied to RTE foods. Rather, heat can
activate spores to germinate and develop into vegetative cells capable of growth during
the stabilization processes of RTE food manufacture.
Consuming foods contaminated with high levels of certain strains of C. perfringens
vegetative cells (those known as type A, that produce the C. perfringens enterotoxin,
CPE) may lead to diarrheal illness. Illness is generally mild, and typically self-limiting,
lasting one or two days. Symptoms inc