Microbiology of Foods MCQs : This section focuses on the "Microbiology of Foods". These Multiple Choice Questions (MCQs) should be practiced to improve the Microbiology of Foods skills required for various interviews (campus interview, walk-in interview, company interview), placement, entrance exam and other competitive examinations.
Question 1
Most spoilage bacteria grow at
A. acidic pH
B. alkaline pH
C. neutral pH
D. any of the pH
Question 2
The microbiological examination of coliform bacteria in foods preferably use
A. MacConkey broth
B. violet Red Bile agar
C. eosine Methylene blue agar
D. All of the above
Question 3
Which of the following acid will have higher bacteriostatic effect at a given pH?
A. Acetic acid
B. Tartaric acid
C. Citric acid
D. Maleic acid
Question 4
Which of the following is not true for the thermal resistance of the bacterial cells?
A. Cocci are usually more resistant than rods
B. Higher the optimal and maximal temperatures for growth, higher the resistance
C. Bacteria that clump considerably or form capsules are difficult to kill
D. Cells low in lipid content are harder to kill than other cells
Question 5
Water activity can act as
A. an intrinsic factor determining the likelihood of microbial proliferation
B. a processing factor
C. an extrinsic factor
D. all of the above
Question 6
Enumeration of microorganism refers to
A. either spiral plating, pour plate or spread plate of a food suspension on to a suitable selective agar, or non-selective plate, depending on the test
B. either spiral plating, pour plate or spread plate of a food suspension on to a suitable selective agar
C. non-selective plating, depending on the test
D. None of these
Question 7
The different ACC's between food categories reflect the
A. expected level of contamination of the raw material
B. potential for microbial growth during storage
C. potential shelf life
D. All of the above
Question 8
Examination of the presence / absence of organisms refers to
A. incubation of a food suspension in an enrichment medium followed by inoculation on to a suitable selective medium.
B. incubation of a food suspension in an enrichment medium followed by inoculation on to a non-selective medium.
C. incubation of a food suspension in an enrichment medium
D. None of these
Question 9
Plate count of bacteria in foods generally use the plating medium consisting of
A. peptone, yeast extract, glucose, sodium chloride, agar and distilled water
B. yeast extract, glucose, sodium chloride, agar and distilled water
C. peptone, glucose, sodium chloride, agar and distilled water
D. peptone, yeast extract, glucose, sodium chloride and distilled water
Question 10
What are the intrinsic factors for the microbial growth?
A. pH
B. Moisture
C. Oxidation-Reduction Potential
D. All of the above
Question 11
Yeast and mould count determination requires-
A. nutrient agar
B. acidified potato glucose agar
C. MacConkey agar
D. violet Red Bile agar
Question 12
The time temperature combination for HTST paterurization of 71.1°C for 15 sec is selected on the basis of
A. Coxiella Burnetii
B. E. coli
C. B. subtilis
D. C. botulinum
Question 13
Aerobic Colony Count (ACC), is also known as
A. Total viable count (TVC)
B. Aerobic plate count (APC)
C. Standard plate count (SPC)
D. All of the above
Question 14
Which of the following is true about ISO 2002 method for Salmonella detection?
A. Selenite cystine (SC) broth is replaced by Muller Kauffmann tetrathionate novobiocin broth (MKTTn)
B. Rappaport Vassiliadis (RV) broth has been replaced by Rappaport Vassiliadis Soya (RVS) broth
C. XLD is the first isolation medium rather than BGA
D. All of the above
Question 15
Suspected colonies of Staphylococcus aureus when grown on Baird-Parker medium shall show
A. coagulase activity
B. protease activity
C. catalase activity
D. None of these
Question 16
A psychrophilic halophile would be a microbe that prefers
A. cold temperatures and increased amounts of salt
B. warm temperatures and increased amounts of pressure
C. cold temperatures and the absence of oxygen
D. warm temperatures and increased amounts of acid
Question 17
NaCl can act as
A. antagonist at optimal concentrations
B. synergistically if added in excess of optimum level
C. Both A and B
D. None of these
Question 18
Aerobic Colony Count (ACC), is also known as
A. Total viable count (TVC)
B. Aerobic plate count (APC)
C. Standard plate count (SPC)
D. All of these
Question 19
Enumeration of microorganism refers to
A. either spiral plating, pour plate or spread plate of a food suspension on to a suitable selective agar, or non-selective plate, depending on the test
B. either spiral plating, pour plate or spread plate of a food suspension on to a suitable selective agar
C. non-selective plating, depending on the test
D. none of the above
Question 20
Examination of the presence / absence of organisms refers to
A. incubation of a food suspension in an enrichment medium followed by inoculation on to a suitable selective medium.
B. incubation of a food suspension in an enrichment medium followed by inoculation on to a non-selective medium.
C. incubation of a food suspension in an enrichment medium
D. none of the above
Question 21
NaCl can act as
A. antagonist at optimal concentrations
B. synergistically if added in excess of optimum level
C. Both (a) and (b)
D. None of the above
Question 22
The microbiological examination of coliform bacteria in foods preferably use
A. MacConkey broth
B. violet Red Bile agar
C. eosine Methylene blue agar
D. all of these
Question 23
What are the intrinsic factors for the microbial growth?
A. pH
B. Moisture
C. Oxidation-Reduction Potential
D. All of these
Question 24
Which of the following is true about ISO 2002 method for Salmonella detection?
A. Selenite cystine (SC) broth is replaced by Muller Kauffmann tetrathionate novobiocin broth (MKTTn)
B. Rappaport Vassiliadis (RV) broth has been replaced by Rappaport Vassiliadis Soya (RVS) broth
C. XLD is the first isolation medium rather than BGA
D. All of these