Module 10

Question 1

Foodborne Illness

Answer 1

Any illness that is related to the consumption of food or contaminants or
toxins in food

Question 2

Pathogens

Answer 2

Microorganisms that can cause disease

Question 3

Toxins

Answer 3

Substances that can cause harm at some level of exposure

Question 4

Cross-contamination

Answer 4

The transfer of one contaminant from one food, piece of equipment or
person to another

Question 5

Threshold effect

Answer 5

Many microorganisms do not cause harm but after reaching their
threshold, however, they can cause foodborne illness

Question 6

Salmonella

Answer 6

• Most common cause of bacterial food-borne illness in the US
• Found in feces.
• Poultry and eggs are the main contaminated foods.
• Also found in dairy, seafood, fresh fruits, and vegetables
• Killed by heat.

Question 7

Campylobacter jejuni

Answer 7

• Leading cause of bacterial diarrhea in US

- Sources: Undercooked chicken. unpasteurized milk, untreated water.

Question 8

Shigella spp

Answer 8

• Contamination usually through fecal-oral route

- Common in salads and raw vegetables.

Question 9

E coli

Answer 9

• Normal inhabitant in GI of all animals

- Undercooked ground beef frequently implicated

Question 10

Listeria monocytogenes

Answer 10

• Fatality rate of 21%
• Fresh soft cheeses, ready-to-eat deli 
meats, hot dogs
• In pregnant women can cause fetal loss 
– Avoid unpasteurized milk and 
cheeses during pregnancy
– Cook (until steaming hot) leftover 
foods or ready-to-eat foods, such as 
hot dogs
– Wash hands to avoid cross-
contamination if preparing these 
foods for others

Question 11

Vibrio spp:

Answer 11

• Grow in warm seawater (especially 
during summer months)
• Organism has been isolated from 
oysters, clams, and crabs
• Consumption of these products raw 
or undercooked may result in illness

Question 12

Bacterial Foodborne Intoxication:

Answer 12

• When illness is caused by toxin produced by
bacteria, not by the organism itself
• Unlike food infections, intoxication can be caused by
only a few microorganisms
• Once formed, toxin cannot be destroyed by cooking
• Most common
– Staphylococcus (staph)
– Clostridium (botulism)

Question 13

Staphylococcus aureus (staph):

Answer 13

• Bacteria live in human nasal passages
– Can be transferred to food through the
coughing or sneezing of food handlers
• Foods frequently contaminated:
– Ham, salads, bakery products and dairy
products

Question 14

Clostridium botulinum (botulism):

Answer 14

• Bacteria produces a neurotoxin – 
deadliest bacterial food-borne toxin
• Toxin causes paralysis (I.e., Botox)
• Botulinal toxin has been found in:
– Improperly canned foods, low-acid 
foods such as potatoes and stews held 
in large containers
– Botulism spores can contaminate 
honey so it should never be fed to 
young children under the age of 1

Question 15

Preventing Oxidation/Rancidity

Answer 15

• Double bonds in fats are susceptible to oxidation
– Rancid butter
– Deep fat fryers
• Oxidation of fruits and vegetables can also turn
them brown
– Apples
– Salad bars

Question 16

Antioxidant food additives

Answer 16

– Vitamin C, Vitamin E
– Sulfites
• In processed foods - alcoholic beverages (wine) and drugs
• “Fruit Fresh” (used to be added to all salad bars)

Question 17

BHA and BHT

Answer 17

• Prevents rancidity in baked goods and snack foods
• Large amounts fed to animals have been shown to reduce
cancer
– Amount in human diet unlikely to be of benefit

Question 18

Purposes of Direct Additives

Answer 18

• To maintain product consistency
– Example: Emulsifiers
•give products a consistent texture
•prevent them from separating 
• To improve or maintain nutrient value
– Vitamins & minerals are added to many foods to 
make up for
•those likely to be lacking in a person's diet
•lost in processing

Question 19

Purposes of Direct Additives

Answer 19

• To maintain palatability & wholesomeness
– Preservatives retard product spoilage caused by
mold, air, bacteria, fungi or yeast
• To provide leavening or control acidity/alkalinity
• To enhance flavor or impart desired color
– Many spices and natural and synthetic flavors
enhance the taste of foods

Question 20

Biotechnology

Answer 20

• Biotechnology is a collection of 
scientific techniques, including genetic 
engineering
• Used to create, improve, or modify 
plants, animals, and organisms  
• Manipulate DNA for the purpose of 
changing the characteristics of an 
organism or creating a new product
• The sequence of bases in genes codes 
for the sequence of amino acids that 
are joined to form proteins.
• The proteins determine the traits of 
organisms.

Question 21

Passing traits from parent to offspring

Answer 21

• When two organisms breed, some genes from each are
passed to the offspring.
• New combinations of genes and the traits for which they
code appear in the offspring.
• Over millions of years, genes have been changed by
mutations.
• Biotechnology speeds up the process of introducing new
traits that can be passed through generations.

Question 22

Traditional breeding vs. Biotechnology

Answer 22

• Almost every fruit, vegetables, or crop grown today has been genetically
modified using traditional selective breeding techniques
– Some of these crops would not have developed without human
intervention
– Allowed us to produce food that is
• more nutritious
• can better withstand harsh environments and resist disease

Question 23

Hybridization

Answer 23

– Process in which two related 
plants are cross fertilized
– Resulting offspring has 
characteristics from both parent 
plants
– These methods introduced the 
genes for traits that add to the 
quality and productivity of 
various plants

Question 24

Crossbreeding

Answer 24

– Used in livestock

– Two types: Inbreeding and Outbreeding.

Question 25

Inbreeding

Answer 25

–crosses between closely related animals to
intensify desirable traits
–but may also intensify undesirable traits

Question 26

Outbreeding

Answer 26

–crosses unrelated animals to reduce
undesirable traits
–increase variability and introduce new traits

Question 27

Techniques of Traditional Breeding

Answer 27

• These techniques work well but they have limitations
– time consuming
– a new trait can only be produced once in the
reproductive cycle of plant or animal
– only same or closely-related species can be interbred
– both desirable and undesirable traits can be
transferred

Question 28

Biotechnology (Cont.)

Answer 28

• Is a more sophisticated, more powerful approach to genetic
modification
– has enormous potential for increasing
• Yield
• Quality of the food supply
– has created safety concerns
• Relies on the techniques of recombinant DNA
– also referred to as genetic modification or genetic
engineering
– to alter the DNA of plants or animals to
• produce new traits
• enhance desirable ones

Question 29

Biotech Method #1:

Answer 29

– Gene is pasted into a loop of bacterial DNA called a
plasmid
– The plasmid, containing the gene of interest, is taken up
by a bacterial cell
– Bacterial cell can then transfer the gene to a plant cell
– Once inside the plant cell, the new DNA migrates to the
nucleus
– The gene for the new trait is integrated into the plant’s
DNA
•The DNA is then referred to as recombinant DNA
– because the DNA from the plasmid has been combined
with the plant’s DNA

Question 30

Biotech Method #2

Answer 30

– Involves painting the desired segment of DNA
onto microscopic metal particles
– These are then loaded into a “gene gun” and
shot into the plant cells
– Once inside the cells, the DNA is washed off
the metal particles by cellular fluids
– DNA migrates to the nucleus
– Is incorporated into the plant’s DNA, forming
recombinant DNA

Question 31

Herbicide resistance:

Answer 31

allows farmers to achieve 
weed-free fields that
–require fewer pesticides
–increase crop yields
–lowers price for 
consumers

Question 32

Insect resistance:

Answer 32

By introducing a gene from 
bacterium Bacillus thuringiensis 
that produces a protein that is 
toxic to certain insects but is 
safe to humans and other 
animals
– the plant produces its own 
insecticide
– environmentally friendly
– reduces the cost of farming

Question 33

Disease resistance

Answer 33

fruits and vegetables have
been modified to resist viral
infections

Question 34

FDA (Food and Drug Administration) GMOs

Answer 34

Regulates safety and labeling of GM foods

Question 35

USDA (U.S. Department of Agriculture) GMOs

Answer 35

Regulates agricultural products and research concerning

development of new plant varieties

Question 36

EPA (Environmental Protection Agency) GMOs

Answer 36

Regulates GM foods that are able to protect themselves

from insects or disease