the food. Also, entry can occur by indirect
contamination through the use of contami-
nated ingredients in processed foods or from
the consumption of foods containing myco-
toxin residues.
Molds that are capable of producing
mycotoxins are frequent contaminants of
food commodities. Those that are important
in the food industry because of potential
mycotoxin production include members of
the genera Aspergillus,Penicillium,Fusarium,
Cladosporium, Alternaria, Trichothecium,
Byssochlamys, and Sclerotinia. Most foods
are susceptible to invasion by these or other
fungi during some stage of production, pro-
cessing, distribution, storage, or merchandis-
ing. If there is mold growth, mycotoxins may
be produced. The existence of mold in a food
product, however, does not necessarily signify
the presence of mycotoxins. Furthermore,
the absence of mold growth on a commodity
does not indicate that it is free of mycotoxins,
because a toxin can exist after the mold has
disappeared.
Of the mycotoxins, aflatoxin is considered
to pose the greatest potential hazard to
human health. It is produced by A. flavus
andA. parasiticus, which are nearly ubiqui-
tous with spores that are widely disseminated
by air currents. These molds are frequently
found among cereal grains, almonds, pecans,
walnuts, peanuts, cottonseed, and sorghum.
These microorganisms will normally not
proliferate unless these commodities are
damaged by insects, not dried quickly, and
not stored in a dry environment. Growth can
occur by the invasion of the kernels with
mold mycelium and subsequent aflatoxin
production on the surface and/or between
cotyledons.
The clinical signs of acute aflatoxicosis
include lack of appetite, listlessness, weight
loss, neurological abnormalities, jaundice of
mucous membranes, and convulsions. Death
may occur. Other evidence of this condition
is gross liver damage through pale color,
other discoloration, necrosis, and fat accu-
mulation. Edema in the body cavity and
hemorrhaging of the kidneys and intestinal
tract may also occur.
Control of mycotoxin production is com-
plex and difficult. Insufficient information
exists regarding toxicity, carcinogenicity, and
teratogenicity to humans, stability of myco-
toxins in foods, and extent of contamination.
Such knowledge is required to establish
guidelines and tolerances. The best approach
to eliminating mycotoxins from foods is to
prevent mold growth at all levels of produc-
tion, harvesting, transporting, processing,
storage, and marketing. Prevention of insect
damage and mechanical damage throughout
the entire process—from production to con-
sumption—as well as moisture control, is
essential. Mycotoxins appear to be produced
at an Awlevel above 0.83, or approximately
8% to 12% kernel moisture, depending on
the type of grain. Therefore, rapid and thor-
ough drying and storage in a dry environ-
ment is necessary. Photoelectric eyes that
examine and pneumatically remove discol-
ored kernels that may contain aflatoxins are
used in the peanut industry to aid in control
and to avoid the difficult, tedious, and costly
process of hand sorting.Other Bacterial Infections
Other bacterial infections that occur in
humans cause illnesses with symptoms simi-
lar to food poisoning. The most common of
these infections is caused by the S. faecalis
bacterium. Although this microorganism is
not a proven pathogen, products manufac-
tured from muscle foods and dairy products
have been implicated in some cases of this ill-
ness. Similar effects have been reported from
infections caused by E. coli. Enterotoxigenic
E. coliis the most common cause of “trav-
eler’s diarrhea,” an illness frequently acquired
by individuals from developed countries