2. Food Spoilage vs. Foodborne
Illness
Food spoilage is any Foodborne illness is
change in food that any illness that is
causes it to be less derived from food.
desirable. Most foodborne illness
E.g. brown bananas; not are caused by
necessarily “bad” but microorganisms
not too appetizing
As the chemicals in
food change, a change
in the smell,
appearance, texture, or
taste may occur
Food spoilage indicates
that conditions may be
favorable for growth of
microorganisms
3. Why does food spoil?
Food spoilage is Microorganisms
caused by the activity Include fungi and
of: bacteria
Microorganisms Enzymes
Enzymes Molecules that speed
up or slow down
Chemicals
chemicals reactions
Chemicals
Harmful chemicals
may result from the
activity of
microorganisms or
enzymes
4. Escherichia coli
Escherichia coli (abbreviated
as E. coli) are a large and
diverse group of bacteria.
Most forms of E. coli are
harmless but some can cause
diarrhea, while others cause
urinary tract
infections, respiratory illness
and pneumonia, and other
illnesses.
The most severe illnesses are
caused by “shiga toxin
producing” E. coli. These
illnesses are spread through
ingestion of tiny particles of
feces (EWWWWW!!!!)
Unfortunately, this happens
more often then we would like
to think.
5. Clostridium Botulinum
Botulism is a rare but serious paralytic
illness caused by a nerve toxin that is
produced by the bacterium Clostridium
botulinum.
Foodborne botulism is a severe type of
food poisoning caused by the ingestion
of foods containing the potent
neurotoxin formed during growth of the
organism. The incidence of the
disease is low, but the disease is of
considerable concern because of its
high mortality rate if not treated
immediately and properly.
Classic symptoms of botulism include
double vision, blurred vision, drooping
eyelids, slurred speech, difficulty
swallowing, dry mouth, and muscle
weakness. Eventually, paralysis of the
extremities and chest muscles leading
to death..
6. Campylobacter jejuni
Campylobacter jejuni is now
recognized as one of the main
causes of bacterial foodborne
disease in many developed
countries.
Most people who become ill with
campylobacteriosis get
diarrhea, cramping, abdominal
pain, and fever within two to five days
after exposure to the organism. The
diarrhea may be bloody and can be
accompanied by nausea and
vomiting. The illness typically lasts
one week. Some infected persons do
not have any symptoms.
In persons with compromised
immune systems, Campylobacter
occasionally spreads to the
bloodstream and causes a serious
life-threatening infection.
7. Salmonella
Salmonella can survive for
weeks outside a living body.
They have been found in
dried excrement after over 2.5
years.
Salmonella are usually
transmitted to humans by
eating foods contaminated
with animal
feces.(EWWWW!)
To protect against salmonella
infection, it is recommended
that food be heated for at
least ten minutes at 75°C
(165° F) (temperature at the
center). The bacteria are not
destroyed by freezing.
8. Vibrio Vulnificus
V. vulnificus causes disease in
•
individuals who eat contaminated
seafood (usually raw or undercooked
oysters) or have an open wound that
is exposed to seawater. Among
healthy people, ingestion of V.
vulnificus can cause
vomiting, diarrhea, and abdominal
pain.
In immunocompromised persons, V.
•
vulnificus can invade the
bloodstream from either a wound or
from the GI tract, causing a severe
and life-threatening illness called
primary septicemia, characterized by
fever, chills, septic shock and death.
V. vulnificus bloodstream
infections are fatal about 50% of
the time.
There was V. vulnificus outbreak in
•
New Orleans after Hurricane Katrina.
9. Aflotoxin
Growth of the fungus on a food
source often leads to
contamination with aflatoxin, a
toxic and carcinogenic
compound. Aspergillus flavus is
also the second leading cause of
aspergillosis in humans. Patients
infected with A. flavus often have
reduced or compromised
immune systems.
Aflatoxin in dry dog food
manufactured by Diamond Pet
Foods was responsible for at
least 23 dog deaths due to liver
failure between Dec 2005 and
early 2006
Almost all peanut products have
an amount of aflotoxins but is it
below the
10. Shellfish Toxins
Shellfish poisoning results from
ingestion of shellfish contaminated
with phycotoxins. These toxins are
produced by micro-algae, upon
which the shellfish feed.
Bivalve shellfish such as clams and
oysters are common vehicles
responsible for shellfish poisoning.
This is because they are filter-
feeders and naturally ingest the
toxic algae in water. When the algae
are toxin-producing, the toxins will
be concentrated in the shellfish
tissue. The amount of toxin in the
shellfish depends on the number of
toxic algae ingested.
The symptoms of shellfish poisoning
range from gastrointestinal (nausea,
diarrhea, cramping) to neurological
(tingling, numbness, disorientation).
The amount and type of toxin
ingested determines the severity of
the sickness.
11. Critical Factors
Factors that affect
the growth or
chemical reactions
of disease causing
microorganisms.
12. Temperature
Very high or very
low temperature can
kill or suppress the
growth of
microorganisms.
Chemical reactions
are usually
suppressed by low
temperature
High temperatures
denature proteins
(enzymes)
13. Acidity (pH)
Acidity has to do with
the chemical
properties of a
solution
Microorganisms
prefer a neutral pH
(around 7)
Anything that has a
pH that is too low or
too high will inhibit the
growth of organisms
and suppress
chemical reactions.
14. Water
Water is needed for
chemical reactions
to occur in
organisms
If no water is
present, it inhibits
the growth of molds
and microorganisms
15. Oxygen
Organisms use oxygen
in chemical reactions
called oxidation
reactions.
Do you remember what
happens when metal
oxidizes? This also
occurs with food.
Oxidation produces
chemicals that may
make food more
susceptible to
microorganism activity.
And it just doesn’t taste
good
