home-canned vegetables and fruits with a
low to medium acid content. Because this
bacterium is anaerobic, canned and vacuum-
packaged foods are also viable sources for
botulism. Canned foods with a swell should
not be eaten because the swelling results
from the gas produced by the organism.
Smoked fish should be heated to at least
83ºC for 30 minutes during processing to
provide additional protection.
To prevent botulism, effective sanitation,
proper refrigeration, and thorough cooking
are essential. This toxin is relatively heat-
labile, but the bacterial spores are very heat-
resistant, and severe heat treatment is
required to destroy them. Thermal process-
ing at 85ºC for 15 minutes inactivates the
toxin. The combinations of temperatures
and times given in Table 3–2 are required to
destroy the spores completely.
Campylobacteriosis
Campylobacterhas become a major con-
cern because it is transmitted by food, espe-
cially inadequately cooked foods and
through cross-contamination. The tempera-
ture for growth ranges from 30 to 45.5ºC
with an optimum of 37 to 42Cº. It survives
to a maximum sodium chloride level of 3.5%
and is inhibited by 2.0%.Campylobacteris
commonly found as commensals of the gas-
trointestinal tract of wild and domesticated
animals. This fastidious, facultative
(microaerophilic-requiring 5% O 2 and 10%
CO 2 ), gram-negative, non-spore-forming,
spiral curve-shaped rod, which is motile by
means of flagella, is now the greatest cause
of foodborne illness in the United States. It
has been identified as the causative agent of
veterinary diseases in poultry, cattle, and
sheep, and is quite common on raw poultry.
As detection and isolation of this microor-
ganism have been improved, it has been
incriminated in foodborne disease out-
breaks. This microbe is now recognized as
one of the most frequent causes of bacterial
diarrhea and other illnesses, and there is a
mounting body of evidence that it causes
ulcers.
The infective dose ofCampylobacteris 400
to 500 bacteria, depending on individual
resistance. The pathogenic mechanisms of
this pathogen allow it to produce a heat-
liable toxin that may cause diarrhea.
Campylobacteriosis can occur at least
twice as frequently as salmonellosis. The
symptoms of foodborne illness from Campy-
lobactervary. Humans with a mild case may38 PRINCIPLES OFFOODSANITATION
Table 3–1Type of Botulinum Toxin
Type Characteristics
A Toxin is poisonous to humans; the most common cause of botulism in the United States
B Toxin is poisonous to humans; found more often than Type A in most soils of the world
C 1 Toxin is poisonous to waterfowl, turkeys, and several mammals, but not to humans
C 2 Toxin is poisonous to waterfowl, turkeys, and several mammals, but not to humans
D Toxin is responsible for forage poisoning of cattle, but rarely poisonous to humans
E Toxin is poisonous to humans; usually associated with fish and fish products
F Toxin is poisonous to humans; only recently isolated and extremely rare
G Toxin is poisonous but rarely found
Table 3–2Temperatures and Times Required to
Completely Destroy C. botulinumSpores
Temperature (ºC) Time (min)
100 360
105 120
110 36
115 12
120 4