Chapter 25

11) Which of the following items that are commonly added during food preparation can be considered a preservative? A) apple juice B) meat broth C) garlic D) yeast E) whey

C) garlic

38) Microbial proteases are used A) in the production of linen. B) as preservatives. C) in spot removers. D) as a component of fabric dyes. E) to biodegrade plastics.

C) in spot removers.

39) Which of the following is an application of proteases? A) cheese B) indigo C) meat tenderizer D) vodka E) wine

C) meat tenderizer

12) An intrinsic factor of food that can determine whether spoilage occurs is A) the degree of processing. B) the amount of preservatives added. C) the storage temperature. D) the water content. E) storage packaging.

D) the water content.

23) Industrial fermentation and fermentation in food production A) are both processes in which sugars are oxidized to alcohols or acids. B) are processes in which sugar or protein is oxidized to produce alcohols or acids. C) use entirely different microorganisms. D) use entirely different starting material. E) make use of the same microorganisms.

D) use entirely different starting material.

1) Control of the fermentation of foods to produce the desired product commonly involves A) careful choice of foodstuffs. B) pretreating the food by boiling. C) adding required nutrients for microbial growth. D) use of a starter culture. E) both pretreating the food by boiling and adding required nutrients for microbial growth.

D) use of a starter culture.

10) Which of the following results when ethanol is allowed to oxidize to acetic acid following the fermentation of fruit, grain, or vegetables? A) beer B) wine C) champagne D) vinegar E) malt

D) vinegar

32) Which of the following microorganisms associated with food poisoning thrives in cold storage? A) Salmonella spp. B) Shigella spp. C) Clostridium botulinum D) Escherichia coli E) Listeria monocytogenes

E) Listeria monocytogenes

14) Which of the following is used in both food production and industrial fermentation? A) Bacillus thuringiensis B) Escherichia coli C) Listeria monocytogenes D) Pseudomonas syringae E) Saccharomyces cerevisiae

E) Saccharomyces cerevisiae

41) A common source of antibiotics is A) Acetobacter. B) Aspergillus oryzae and Lactobacillus. C) Lactoccocus cremoris. D) Streptococcus thermophilus. E) Streptomyces.

E) Streptomyces.

18) Undercooked shellfish contaminated with ________ can lead to foodborne illness. A) Toxoplasma gondii B) Campylobacter jejuni C) Listeria monocytogenes D) Yersinia enterocolitica E) Vibrio vulnificus

E) Vibrio vulnificus

26) Municipal chlorinated water contains A) no viruses. B) no bacteria at all. C) no endospores. D) no cysts. E) a decreased microbial load.

E) a decreased microbial load.

2) A researcher studying the impact of agricultural pesticides on native plants discovers a bacterium capable of degrading small amounts of a specific pesticide. The researcher then modifies the bacterial species in the lab to increase the rate of pesticide degradation. This research represents A) applied microbiology. B) environmental microbiology. C) food microbiology. D) both food microbiology and environmental microbiology. E) both applied microbiology and environmental microbiology.

E) both applied microbiology and environmental microbiology.

31) Which of the following additives help preserve food as well as enhancing flavor? A) cinnamon B) garlic C) salt D) salt and pepper E) cinnamon, garlic, and salt

E) cinnamon, garlic, and salt

25) Potable water is water that A) is considered safe to drink because it is completely sterile. B) contains biosensors. C) contains a dangerous number of microorganisms. D) is transferred from one place to another. E) contains low amounts of microorganisms and is considered safe to drink.

E) contains low amounts of microorganisms and is considered safe to drink.

24) During treatment of water to make it potable, about 90% of the microbes are removed A) by preliminary fermentation. B) in the sedimentation step. C) by treatment with biosensors. D) by treatment with chlorine or ozone. E) in the filtration step.

E) in the filtration step.

13) Pickling is an effective means of food preservation involving A) increasing oxygen content. B) increasing salt concentration. C) reducing pH. D) reducing oxygen content. E) increasing salt concentration or reducing pH or both.

E) increasing salt concentration or reducing pH or both.

37) Which of the following may result from eating shellfish? A) botulism B) norovirus infection C) polio D) salmonellosis E) paralysis

E) paralysis

29) Which of the following is produced by fermentation? A) beef jerky B) pasteurized milk C) pepperoni D) mozzarella cheese E) pepperoni and mozzarella cheese

E) pepperoni and mozzarella cheese

42) Which of the following may result from eating tuna sashimi (raw fish)? A) botulism B) norovirus infection C) polio D) salmonellosis E) saxitoxin intoxication

E) saxitoxin intoxication

10) Water contamination refers only to the presence of excess or non-endemic microbes.

FALSE

2) The starter culture used to make cheese determines the type of cheese produced.

FALSE

4) Pasteurization is a more rigorous process than canning.

FALSE

6) Canned foods are prepared using the same temperature as is used for autoclaving.

FALSE

7) Through recombinant DNA technology, many plants now can manufacture their own Bt toxin, which improves fermentation.

FALSE

1) Most microbes need an environment that has a water activity of at least 0.90.

TRUE

3) Amino acid and vitamin supplements are prepared from extracts of microbial cultures.

TRUE

5) Cold is preferred for storing food because it retards microbial growth by slowing down metabolic processes.

TRUE

8) Reducing the water content of food is a highly effective way of reducing food spoilage.

TRUE

9) Food poisoning is often the result of ingesting microbial toxins, not the microbes themselves.

TRUE

35) Which of the following is a waterborne pathogen that causes severe diarrhea? A) Entamoeba histolytica B) Naegleria fowleri C) Campylobacter jejuni D) Toxoplasma gondii E) Gonyaulax species

A) Entamoeba histolytica

27) Which of the following microorganisms is the most commonly used indicator organism for water quality testing? A) Escherichia coli B) Salmonella spp. C) Shigella spp. D) Campylobacter jejuni E) Hepatitis A virus

A) Escherichia coli

4) Why are "fortified" foods more likely to spoil than are unfortified foods? A) The addition of vitamins or minerals makes the food more nutritious for microbes as well as humans. B) Vitamins are added to "fortified" foods by adding the microbes that produce the vitamins to the food item. C) Every step of modification or manipulation of food increases the chance for contamination. D) The addition of nutrients creates an osmotic environment suitable for a wide range of microbes. E) The vitamins require a neutral pH environment, which is suitable for many microbes.

A) The addition of vitamins or minerals makes the food more nutritious for microbes as well as humans.

22) What was the first substance produced by microorganisms to be used pharmaceutically? A) penicillin B) streptokinase C) taxol D) human insulin E) interferons

A) penicillin

17) What is the significance of the industrial practice of waiting for cultures to enter the stationary phase of growth before harvest? A) The cells are at peak metabolic activity. B) Secondary metabolites are often the desired product, and are only produced in stationary phase. C) The desired primary metabolites are produced in stationary phase. D) Potential toxins from log phase growth have been depleted. E) An optimal combination of primary and secondary metabolites is being produced.

B) Secondary metabolites are often the desired product, and are only produced in stationary phase.

7) Sulfur dioxide is added to "must" in the production of wine to A) improve the flavor. B) allow more control over the fermentation process. C) provide a necessary nutrient for the fermentation process. D) prevent tannins from leaching out of wood into the fermenting wine. E) both enhance flavor and promote fermentation.

B) allow more control over the fermentation process.

33) Secondary metabolites are often useful, and are obtained by A) harvesting a culture during log phase. B) allowing a culture to enter stationary phase. C) growing a culture at sub-optimal temperature. D) adding chemicals that alter metabolic pathways. E) using continuous flow culturing.

B) allowing a culture to enter stationary phase.

9) Which of the following beverages is made from fermented fruit? A) beer B) brandy C) sake D) vodka E) both beer and vodka

B) brandy

30) Which of the following is the CORRECT sequence of steps for beer preparation? A) mashing, malting, fermentation, clarification, aging B) malting, mashing, adding hops, fermentation, aging C) mashing, malting, fermenting, aging, clarification D) malting, fermenting, adding hops, clarification, aging

B) malting, mashing, adding hops, fermentation, aging

43) Soy sauce is made using A) Acetobacter. B) Aspergillus oryzae and Saccharomyces. C) Aspergillus oryzae and Lactobacillus. D) Saccharomyces. E) Lactoccocus cremoris.

C) Aspergillus oryzae and Lactobacillus.

19) Food contaminated with ________ may contain a potent neurotoxin. A) Salmonella spp. B) Shigella spp. C) Clostridium botulinum D) Escherichia coli E) Listeria monocytogenes

C) Clostridium botulinum

5) Which of the following is a lactic acid bacterium used in the production of food? A) Aspergillus oryzae B) Gluconobacter C) Leuconostoc D) Penicillium E) Saccharomyces cerevisiae

C) Leuconostoc

8) Why is the pasta you buy from the grocery store shelf considered a nonperishable food? A) It has a low nutritional content. B) It was sterilized during preparation. C) The low moisture content prevents microbial growth. D) Various preservative chemicals are added. E) Microbes present in the pasta inhibit the growth of harmful microbes.

C) The low moisture content prevents microbial growth.

6) The fermentation product known as silage is A) a step in the production of brandy. B) a means of food preservation. C) a means of making plant materials more appealing to livestock. D) a meat product. E) made from milk.

C) a means of making plant materials more appealing to livestock.

21) Which of these microbial products is needed to produce "gasohol"? A) citric acid B) methanol C) ethanol D) hyaluronidase E) aspartame

C) ethanol

28) Which of the following statements concerning the biochemical oxygen demand (BOD) is CORRECT? A) It is a measure of the amount of oxygen in water. B) It is proportional to how potable water is. C) It is used as a bioreceptor index. D) It is a measurement of the amount of oxygen that aerobic bacteria require to decompose organic wastes in water. E) It is a filter system to purify drinking water.

D) It is a measurement of the amount of oxygen that aerobic bacteria require to decompose organic wastes in water.

34) A patient is brought to the emergency room in a comatose state. The family reports he had complained of nausea and a bad headache in the past couple of days. They also report they had engaged in their normal summer activities: picnicking, fishing and swimming at the lake near their home. His fever is high, and while in the ER, he has a seizure. Which of the following is likely to be responsible for his symptoms? A) Entamoeba histolytica B) Giardia intestinalis C) Gonyaulax D) Naegleria fowleri E) Toxoplasma gondii

D) Naegleria fowleri

36) Which of the following is a microbial product used to reduce crop damage? A) Bt toxin B) saxitoxin C) ice-minus D) both Bt toxin and ice-minus E) both Bt toxin and saxitoxin

D) both Bt toxin and ice-minus

3) Sourdough bread is produced using A) yeast. B) Aspergillus oryzae. C) lactic acid bacteria. D) both yeast and lactic acid bacteria. E) both Aspergillus oryzae and lactic acid bacteria.

D) both yeast and lactic acid bacteria.

40) Streptokinase is useful for which of the following? A) producing antibiotics B) cheese production C) biosensors D) dissolving blood clots E) insecticide

D) dissolving blood clots

15) Sugar and salt act as preservatives by A) inhibiting bacterial enzymes. B) producing oils that inhibit bacterial growth. C) inhibiting DNA replication. D) drawing water out of microbes. E) killing endospores.

D) drawing water out of microbes.

16) Which of the following methods of preserving food sterilizes it? A) canning B) pasteurization C) drying D) gamma radiation E) lyophilization

D) gamma radiation

20) Which of the following pairs of industrial microbial products and their uses is MISMATCHED? A) streptokinase; dissolving blood clots B) indigo; cloth dye C) citric acid; antioxidant in food D) gluconic acid; release of cellulose from flax to make linen E) phenylalanine; the sweetener aspartame

D) gluconic acid; release of cellulose from flax to make linen