The Relationship of Microorganisms to Sanitation 51- Changes in perception and awareness of
what constitutes hazards, risks, and
hygiene. Advances in epidemiology,
especially the collection of data by
computer, have contributed to the
recognition of foodborne listeriosis. - Demographic changes. Ill and immuno-
compromised people are kept alive
much longer, increasing the probability
of new infections. Tourism and immi-
gration may affect the emergence of
certain disease.
4.Changes in food production. Large-scale
production of raw materials increases
the possibility of creating ecologic
niches where microorganisms may
grow and from which they may be
spread. Fruits and vegetables grown in
countries with less rigid hygienic prac-
tices have introduced additional con-
tamination. - Changes in food processing. The use of
vacuum packaging and chill storage
could affect the survival of facultative
microorganisms.
6.Changes in food handling and prepa-
ration. Longer storage life of foods
such as vegetables, salads, soft cheeses,
and muscle foods can give rise to
psychrotrophic pathogens, such as
L. monocytogenes.
7. Changes in the behavior of microorgan-
isms. Many of the factors responsible
for pathogenicity are determined by
plasmids that can be transferred from
one species to another. The emergence
of foodborne diseases is the result of
complex mutual interaction of many
factors. New microbial hazards can be
the result of a change in behavior of
microorganisms not previously recog-
nized as pathogens and the occurrence
of conditions allowing the expression
of these changes.
Mycotoxins
Mycotoxins are compounds or metabo-
lites produced by molds that are toxic or
have other adverse biological effects on
humans and animals (Table 3–4). They are
produced from a wide range of fungi. The
acute diseases caused by mycotoxins are
calledmycotoxicoses. Mycotoxicoses are not
common in humans. However, epidemiologic
evidence suggests an association between
primary liver cancer and aflatoxin, one type
of mycotoxin, in the diet. In large doses,
aflatoxins are acutely toxic, causing gross
liver damage with intestinal and peritoneal
hemorrhaging, resulting in death. Mycotox-
ins may enter the food supply by direct con-
tamination, resulting from mold growth onTable 3–4Mycotoxins of Significance to the Food Industry
Mycotoxin Major* Producing Microorganism Potential Foods Involved
Aflatoxin Aspergillus flavus, Aspergillus parasiticus Cereal, grains, flour, bread, corn meal,
popcorn, peanut butter
Patulin Penicillium cyclopium, Penicillium expansanum Appeals and apple products
Penicillic acid Aspergillus species Moldy supermarket foods
Ochratoxin Aspergillus ocharaceus, Penicillium vitidicatum Cereal grains, green coffee beans
Sterigmatocystin Aspergillus versicolor Cereal grains, cheese, dried meats,
refrigerated and frozen pastries
*Other genera and species may produce these mycotoxins.