Deck 36: Food Preservation and Foodborne Microbial Diseases

Question 1

Severe cases of Staphylococcus aureus food poisoning may require treatment

A) with cleansing enemas.
B) for dehydration.
C) with powerful antibiotics.
D) of all of the above.

Answer 1

B

Question 2

A sealed homogenization system, which avoids aerosolization of any foodborne microbial contaminants and prevents outside microbial contamination of the food, is called a sealed

A) paddler.
B) stomacher.
C) blender.
D) food processor.

Answer 2

B

Question 3

The most common source of individual foodborne botulism outbreaks are due to consumption of

A) egg and meat salads.
B) dairy products.
C) nonacid, home- canned vegetables.
D) honey.

Answer 3

C

Question 4

At what temperature are most household freezers kept?

A) 4°C
B) - 20°C
C) - 80°C
D) 0°C

Question 5

Flour and sugar are classified as foods.

A) semiperishable
B) selectively perishable
C) nonperishable
D) highly perishable

Question 6

Staphylococcus aureus is a common foodborne disease, because it

A) grows on many common foods.
B) produces several heat- stable enterotoxins.
C) is a member of the normal flora on some humans that work with food processing.
D) is all of the above.

Question 7

Which of the following type of rays uses radioactive elements such as 60Co and 136Cs for irradiation?

A) beta
B) X
C) alpha
D) gamma

Question 8

Isolation and identification procedures for microbial food contaminants should include which of the following?

A) inoculation onto enriched media, followed by differential or selective media, and finally by molecular methods
B) inoculation onto differential media, followed by enriched media, followed by selective media, followed by molecular or genetic methods
C) genetic fingerprinting techniques followed by either enriched media or selective/differential media for confirmation
D) inoculation onto differential media, followed by enriched media, or genetic fingerprinting techniques

Question 9

The Campylobacter spp. are

A) facultative anaerobes.
B) microaerophiles.
C) anaerobes.
D) aerobes.

Question 10

Vinegar is actually dilute

A) phosphoric acid.
B) hydrochloric acid.
C) acetic acid.
D) sulfuric acid.

Question 11

In preventing listeriosis, raw food and food- handling equipment can be decontaminated with

A) radiation.
B) cold storage.
C) antibiotic spray.
D) all of the above.

Question 12

Verotoxin can cause

A) brain damage.
B) liver failure.
C) hemorrhagic, or "traveler's," diarrhea.
D) all of the above.

Question 13

The type of Escherichia coli that produces a verotoxin similar to the one produced by Shigella dysenteriae is

A) enteroimmunogenic E. coli.
B) enterotoxigenic E. coli.
C) enteropathogenic E. coli.
D) enterohemorrhagic E. coli.

Question 14

Listeriosis is diagnosed from and treated with .

A) blood or spinal fluid cultures / hydration therapy
B) sputum cultures / intravenous antibiotics
C) blood or spinal fluid cultures / intravenous antibiotics
D) sputum cultures / hydration therapy

Question 15

The Staphylococcus aureus toxins are

A) ectotoxins.
B) endotoxins.
C) superantigen toxins.
D) exotoxins.

Question 16

What organisms are good competitors for free water present in foods with low aw?

A) gram- negative bacilli
B) gram- positive bacilli
C) gram- positive cocci
D) fungi

Question 17

The degree of susceptibility a food has to microbial activity is determined by (its)

A) water content.
B) chemical characteristics.
C) physical characteristics.
D) all of the above.

Question 18

Prions are

A) proteins, presumably of nonhost origin.
B) carbohydrates, presumably of nonhost origin.
C) proteins, presumably of host origin.
D) carbohydrates, presumably of host origin.

Question 19

Psychrotolerant microorganisms can survive and grow at

A) high salt or sugar concentrations.
B) boiling temperatures.
C) refrigeration temperatures.
D) extreme fluctuations in water availability.

Question 20

Clostridium botulinum is a(n) that produces a(n) .

A) gram- negative rod / endotoxin
B) gram- positive endospore- forming rod / exotoxin
C) gram- negative rod / exotoxin
D) gram- positive endospore- forming rod / endotoxin

Question 21

The degree of perishability of a food is closely related to its content.

Question 22

Which organisms are NOT involved in food fermentations?

A) acetic acid bacteria
B) sulfuric acid bacteria
C) lactic acid bacteria
D) propionic acid bacteria

Question 23

Clostridium perfringens food poisoning leads to diarrhea, because the

A) organism multiplies more rapidly than the immune system can handle.
B) toxin causes the shedding of the intestinal lining.
C) permeability of the intestinal epithelium is altered.
D) disease causes such extreme thirst that the patient drinks more water than can be absorbed.

Question 24

The principle behind salt or sugar preservation is to

A) introduce a mechanical barrier to microbial invasion.
B) introduce a microbicide in anticipation of contaminating bacteria or fungi.
C) reduce water availability (aw).
D) accomplish all of the above, depending on the food being preserved.

Question 25

The major reason why it is unlikely that any new chemical preservatives will be added to the list of approved chemical preservatives in the near future is that

A) chemically, all logical compounds have been identified or synthesized.
B) new preservatives are already being added several times per year.
C) testing programs are lengthy and costly.
D) there is no need, so there is no reason to work on further discovery.

Question 26

Two organisms that are commonly the target of irradiation are _ and _.

Question 27

Which statement is TRUE?

A) There are approximately 100,000 cases of shigellosis per year.
B) Reheating food may kill Bacillus cereus, but the toxin remains active.
C) Yersinia enterocolitica can cause a life- threatening disease.
D) All of the above are true.

Question 28

The most prevalent reported cause of food poisoning in the United States is

A) Staphylococcus aureus.
B) Salmonella typhimurium.
C) Clostridium perfringens.
D) Clostridium botulinum.

Question 29

When solute is added to food products, the water activity (aw)

A) remains the same.
B) increases.
C) decreases.
D) initially increases and then decreases.

Question 30

Which of the following can be stored for the longest time without suffering spoilage?

A) nonperishable food
B) semiperishable food
C) perishable food
D) all of the above

Question 31

ETEC strains produce one of two _ diarrhea- producing _ .

A) heat- labile / enterotoxins
B) heat- labile / endotoxins
C) heat- stable / endotoxins
D) heat- stable / enterotoxins

Question 32

The pH of most foods is

A) neutral or acidic.
B) acidic.
C) neutral or basic.
D) basic.

Question 33

Listeria monocytogenes is

A) salt tolerant.
B) acid tolerant.
C) cold tolerant.
D) all of the above.

Question 34

What concentration of NaCl inhibits nearly all bacterial growth (with the exception of some gram- positive cocci)?

A) 5%
B) 10%
C) 2.5%
D) 7.5%

Question 35

The rate of contaminant microbial growth during the exponential phase in food depends on

A) the nutrient value of the food.
B) other growth conditions.
C) temperature.
D) all of the above.

Question 36

What items are MOST routinely irradiated in the United States?

A) canned foods
B) herbs and spices
C) fresh fruits
D) fish

Question 37

Salmonellosis is most frequently caused by

A) Shigella botulinosium.
B) Salmonella typhi.
C) Shigella dysenteriae.
D) Salmonella typhimurium.

Question 38

Pickling is a type of food preservation utilizing

A) lyophilization.
B) weak acids.
C) basic substances.
D) irradiation.

Question 39

Enteric bacteria such as Salmonella spp., Shigella spp., and Escherichia spp. often contaminate and spoil

A) milk and milk products.
B) fruits.
C) vegetables.
D) meat.

Question 40

Which of the following chemical preservatives has NOT been demonstrated to pose a human health hazard?

A) sodium propionate
B) ethylene oxide
C) propylene oxide
D) nitrites

Question 41

For growth studies of nonliquid foods, usually the first step includes .

Question 42

Any change in the appearance, smell, or taste of a food product that makes it unacceptable to the consumer is termed .

Question 43

Immunocompromised persons should avoid nonpasteurized dairy products and ready- to- eat processed meats, because _ .

Question 44

Properly canned foods technically have an indefinite shelf life, because .

Question 45

Food contains _ nutrients, thus contaminants would be nutritionally classified as
.

Question 46

There are about 200 known diarrheal and urinary tract infection (UTI)- causing pathogenic strains of .

Question 47

Production of the perfringens enterotoxin begins in the .

Question 48

Listeria monocytogenes is a(n) pathogen and is taken up by and replicates in
.

Question 49

Toxoplasmosis is generally mild and self- limiting, except .

Question 50

The organism known as O157:H7 is a strain of .

Question 51

Common sources of listeriosis include , , , and .

Question 52

The time required for a microbial population to reach a significant level depends on the
and the .

Question 53

Diagnosis of perfringens food poisoning is usually made by or .

Question 54

Campylobacter fetus is economically important because it is a(n) .

Question 55

The shiitake mushroom (Lentinus edulus) is cultivated on tree logs but specifically grows by degrading .

Question 56

The secondary addition of _ and produce the blue veins and distinctive taste and aroma of blue cheese.

Question 57

The causative agent for new variant Creutzfeldt- Jakob Disease is a(n) _.

Question 58

The least damaging physical method used to dry foods is _.

Question 59

Campylobacter jejuni is a normal resident in the intestinal tract of , and virtually all
and _ normally have this organism.

Question 60

The principle symptoms of Staphylococcus aureus food poisoning are , _,
, and these typically occur within hours following consumption of contaminated food.

Question 61

Nearly all cases of acute listeriosis require hospitalization.

Question 62

Mass- processed ground meat is a particularly common source of infection with EHEC.

Question 63

Escherichia coli is found naturally only in the intestines of animals.

Question 64

To be certain the botulinum toxin is inactivated, the source must be heated for at least 2 minutes at not less than 100°C.

Question 65

For certain bacteria (such as lactic acid bacteria and acetic acid bacteria), food fermentation is a self- limiting process. This is because these processes produce .

Question 66

Properly canned foods are necessarily sterile.

Question 67

Conditions of pH or less inhibit the growth of most spoilage organisms.

Question 68

For much of the period of microbial growth in a food, there is no visible or easily detectable change in food quality.

Question 69

Foodborne diseases are classified as one or the other: a food intoxication or a food infection.

Question 70

It is estimated that less than 4% of all cases of salmonellosis are reported.

Question 71

Microbial growth usually reduces both food quality and availability.

Question 72

Many food infection agents also cause waterborne diseases.

Question 73

Ideally, microbes should be eliminated from all foods.

Question 74

Food poisoning results from the ingestion of food containing preformed microbial toxins.

Question 75

Antibiotic therapy is not significantly useful for treating typhoid fever.

Question 76

Toxoplasmosis is generally mild and self- limiting, except during pregnancy because of fetal complications, and for immunocompromised patients.

Question 77

Treatment of all pathogenic E. coli infections involves supportive therapy and, in some cases, may also include antimicrobial drugs.

Question 78

Most foodborne disease outbreaks are caused by by consumers.

Question 79

Infection by Campylobacter fetus can result in infertility in both cattle and sheep.

Question 80

With Clostridium perfringens the toxin is present in the endospores that germinate under anoxic conditions.