1. Introduction
The EU has established microbiological food safety criteria for
Listeria monocytogenes in Ready To Eat (RTE) foods in Regulation
(EC) 2073/2005, amended in 1441/2007. Food business operators at
all stages of the food chain must comply with the relevant microbial
criteria. With regard to L. monocytogenes, two categories of food are
defined according to whether or not they are able to support the
growth of L. monocytogenes, with different standards applying. A
100 CFU/g limit applies throughout the shelf-life of marketed RTE
foods that are unable to support the growth of L. monocytogenes. In
RTE foods that are able to support the growth of L. monocytogenes
and may pose a public health risk, the pathogen must be absent (in
25 g of product) “before the food has left the immediate control of the
food business operator who has produced it”. The 100 CFU/g limit is
allowable in this food category if the manufacturer is able to
demonstrate that the product will not exceed this limit throughout
its shelf-life and provides a guarantee by fixing intermediate limits
during processing. The above-mentioned Commission regulation
specifies that “As necessary, the food business operators responsible
for the manufacture of the product shall conduct studies … in order to
investigate compliance with the criteria throughout the shelf-life”. The
regulation also specifies that the studies “shall include: d specifi-
cations for physico-chemical characteristics of the product, such as pH,
aw, salt content, concentration of preservatives and type of packaging
system, taking into account the storage and processing conditions, the
possibilities for contamination and the foreseen shelf-life, and d
consultation of available scientific literature and research data
regarding the growth and survival characteristics of the microorganisms
of concern”. In light of this regulation, the operators in