Explore topic-wise MCQs in Dairy Engineering.

This section includes 533 Mcqs, each offering curated multiple-choice questions to sharpen your Dairy Engineering knowledge and support exam preparation. Choose a topic below to get started.

1.

Traveller's diarrhea is caused by

A. enteropathogenic Escherichia coli (EPEC)
B. entero invasive E. coli (EIEC)
C. entero toxigenic E. coli (ETEC)
D. entero haemorrhagic E. coli (EHEC)
Answer» D. entero haemorrhagic E. coli (EHEC)
2.

Which of the following species of Clostridium is responsible for the formation of dark green to black colors in cheese?

A. Clostridium tyrobutyricum
B. Clostridium sporogenes
C. Clostridium herbarum
D. None of the mentioned
Answer» D. None of the mentioned
3.

Cheese cancer of Swiss and similar cheese is caused by?

A. Oospora Crustacea
B. Oospora caseovorans
C. Oospora aurianticum
D. S. cremoris
Answer» C. Oospora aurianticum
4.

The yoghurt is made from ________

A. Lactobacillus bulgaricus
B. Streptococcus thermophilus
C. S. cremoris
D. Mixed culture of Lactobacillus bulgaricus and Streptococcus thermophilus
Answer» E.
5.

Non bacterial ropiness or sliminess in milk and milk products may be due which of the following reasons?

A. Stringiness due to mastitis and in particular by fibrin and leucocytes from the cow’s blood
B. Sliminess resulting from the thickness of the cream
C. Stringiness due to thin films of casein or lactalbumin during cooling
D. Cleanliness
Answer» E.
6.

Which bacteria are also known as “The cheese destroyer”?

A. Propionic acid bacteria
B. Coliform
C. Lactic acid bacteria
D. Butyric acid bacteria
Answer» E.
7.

Presence of coliform in milk pipelines after pasteurization indicates __________

A. Excessive hygiene
B. Poor sanitation
C. Rusting
D. Coating
Answer» C. Rusting
8.

Milk secreted in the udder is virtually sterile.

A. True
B. False
Answer» B. False
9.

Transfer of plasmids from one cell to another can also be done conjugation. The plasmid to be transferred known as ______ is often unable to do so by itself and thus it relies on other plasmids known as ______

A. cargo, conjugal
B. conjugal, cargo
C. cargo, helper
D. conjugal, helper
Answer» B. conjugal, cargo
10.

Natural transformation can be relieved by the use of protoplasts, in the presence of osmotic buffer and polyethylene glycol. What are protoplasts?

A. Protoplasts are the cells from which cell membrane has been removed
B. Protoplasts are the cells from which cell wall has been removed
C. Protoplasts are the cells from which vacuole has been removed
D. Protoplasts are the cells from which golgi bodies are removed
Answer» C. Protoplasts are the cells from which vacuole has been removed
11.

Competence is determined by the excretion into growth medium of _______ & _________ proteins called as competence proteins.

A. cellular & high molecular weight
B. cellular & low molecular weight
C. extracellular & low molecular weight
D. extracellular & high molecular weight
Answer» D. extracellular & high molecular weight
12.

Gram-positive Bacillus, Streptococcus and Streptomyces include species that don’t exhibit natural competence.

A. True
B. False
Answer» C.
13.

If a plasmid can’t be transferred from one cell to another, then it is called as ___________

A. non-transmissible
B. non-mobilizable
C. untransferrable
D. immobilized
Answer» C. untransferrable
14.

If plasmids direct their own transfer from one bacterium cell to another, then they are called as ___________

A. self-transmissible
B. auto-transmissible
C. autonomously replicating
D. auto-transfer
Answer» B. auto-transmissible
15.

E.coli is a gram negative bacterium.

A. True
B. False
Answer» B. False
16.

An organism containing a gene which doesn’t belong to it and is derived from somewhere else then the organism is said to be ___________

A. transformed
B. transgenic
C. mutant
D. modified
Answer» C. mutant
17.

Which of the following Staphylococcal haemolysins does not possess leucocidal activity?

A. α haemolysin
B. γ haemolysin
C. β haemolysin
D. δ haemolysin
Answer» D. δ haemolysin
18.

An organism has an optimal growth rate when the hydrogen ion concentration is very high. This organism is

A. osmotolerant
B. acidophile
C. neutrophile
D. aerotolerant anaerobe
Answer» C. neutrophile
19.

Slime capsule often covers the

A. bacterium
B. virus
C. fungi
D. all of above
Answer» B. virus
20.

Lactobacilli grow best under

A. strict anaerobic conditions
B. microaerophilic conditions in presence of 5% CO2 and PH6
C. microaerophilic conditions in presence of 3% CO2 and PH5
D. microaerophilic conditions in presence of 2% CO2 and PH4
Answer» C. microaerophilic conditions in presence of 3% CO2 and PH5
21.

Types of exotoxin, most commonly associated with botulism in man, is/are?

A. Type A
B. Type B
C. Type E
D. All of these
Answer» E.
22.

In 'binary fission' parent cell divides to form

A. 2 progeny cells
B. 4 progeny cells
C. 8 progeny cells
D. 16 progeny cell
Answer» B. 4 progeny cells
23.

The cell walls of Corynebacterium contain mycolic acid containing ______________ carbon atoms.

A. 2 to 3
B. 100 to 150
C. 32 to 36
D. 20 to 25
Answer» D. 20 to 25
24.

Agglutination test for Brucella mainly identifies which class of antibodies?

A. IgG
B. IgM
C. IgA
D. IgE
Answer» C. IgA
25.

Bacteria are

A. saprophytic
B. symbiotic
C. hyper parasitic
D. all of these
Answer» B. symbiotic
26.

The generation time of a culture that produces two generations per hour is

A. greater than that produces three generations per hour
B. lesser than that produces three generations per hour
C. equal to that produces three generations per hour
D. none of the above
Answer» B. lesser than that produces three generations per hour
27.

What are the extrinsic factors for the microbial growth?

A. humidity
B. storage temperature
C. composition of gas phase
D. all of these
Answer» E.
28.

Colonies resembling molar teeth are produced by

A. Nocardia brasiliensis
B. N. asteroids
C. Actinomyces israelii
D. Actinomadura madurae
Answer» D. Actinomadura madurae
29.

In viruses with envelopes

A. the envelope and the embedded proteins are encoded by the viral nucleic acid
B. the envelope is derived from the host but it contains embedded proteins coded by the viral nucleic acid
C. the envelope is coded by the viral nucleic acids, but the proteins come from the host's membrane proteins
D. the envelope and its imbedded proteins are derived from the host's membranes
Answer» C. the envelope is coded by the viral nucleic acids, but the proteins come from the host's membrane proteins
30.

Which of the following genus of species play an active role in the decomposition of urea?

A. Bacillus
B. Sporosarcina
C. Clostridium
D. Desulfotomaculum
Answer» C. Clostridium
31.

Volutin granules stain which colour with dilute methylene blue?

A. Violet
B. Blue
C. Red
D. Reddish purple
Answer» E.
32.

Protein A is found in cell wall of

A. coagulase-negative staphylococci
B. Staphylococcus aureus
C. Micrococci
D. none of these
Answer» C. Micrococci
33.

Lyticum flagellatum is an endosymbiont carried by certain strains of __________________

A. bacteria
B. fungi
C. viruses
D. protozoa
Answer» E.
34.

Chitin is a form of

A. complex peptone
B. complex DNA
C. complex plasmids
D. complex carbohydrates
Answer» E.
35.

The cocci belonging to the family Dienococcaceae occur mainly in _______________

A. tetrads
B. diplococci
C. streptococci
D. staphylococci
Answer» B. diplococci
36.

Which of the following does not cause wound infection following exposure to sea water or infected shellfish?

A. Vibrio vulnificus
B. V. alginolyticus
C. V. cholerae
D. Aeromonas
Answer» D. Aeromonas
37.

The growth is normally expressed as __________ in turbidimetric measurement

A. cells per ml
B. cfu/ml
C. optical density
D. mg N2 /ml
Answer» D. mg N2 /ml
38.

The organisms that can be acid-fast stained is

A. Nocardia
B. Tubercle bacilli
C. Lepra bacilli
D. all of these
Answer» E.
39.

Gram staining was developed accidentally in 1884 by

A. Alexander Fleming
B. Hans Christian Gram
C. Joseph Christian Gram
D. Robert Gram
Answer» C. Joseph Christian Gram
40.

During exponential growth, the growth rate is

A. number of generations per unit time
B. reciprocal of generation time
C. both (a) and (b)
D. none of these
Answer» C. both (a) and (b)
41.

Members of the genus Mycobacterium are

A. gram-positive
B. acid-fast
C. non-motile
D. all of these
Answer» E.
42.

Saprophytic bacteria feeds on

A. intestines of animals
B. by producing their own food
C. decaying organic matter
D. decaying inorganic substances
Answer» D. decaying inorganic substances
43.

Crystal violet blood agar is a selective medium for

A. β-haemolytic streptococci
B. Staphylococcus aureus
C. Corynebacterium diphtheriae
D. Mycobacterium tuberculosis
Answer» B. Staphylococcus aureus
44.

The deinococci are gram-positive cocci and rods that are distinctive in their unusually great resistance to

A. radiation
B. desiccation
C. both (a) and (b)
D. extreme temperatures
Answer» D. extreme temperatures
45.

Mycobacteria are acid-fast organisms.

A. True
B. False
C. May be
D. Can't say
Answer» B. False
46.

Acute diarrhoeal disease resembling cholera can be caused due to

A. Aeromonas hydrophila
B. Vibrio vulnificus
C. V. alginolyticus
D. All of these
Answer» B. Vibrio vulnificus
47.

The transport medium for Vibrio cholerae can be

A. Venkatraman-Ramakrishnan medium
B. Selenite F broth
C. Tetrathionate broth
D. Nutrient broth
Answer» B. Selenite F broth
48.

Which of the following Nonspore forming Gram-positive rods show negative result for catalase test?

A. Lactobacillus
B. Kurthia
C. Brocothrix
D. Renibacterium
Answer» B. Kurthia
49.

What is the order of reagents used in the Gram stain?

A. Crystal violet, iodine, safranin, decolorizer
B. Crystal violet, iodine, decolorizer, safranin
C. Safranin, crystal violet, decolorizer, iodine
D. Crystal violet, safranin, iodine, decolorizer
Answer» C. Safranin, crystal violet, decolorizer, iodine
50.

At what concentration of sulphuric acid, Nocardia resists decolourization?

A. 0.5% sulphuric acid
B. 5% sulphuric acid
C. 10% sulphuric acid
D. 8% sulphuric acid
Answer» B. 5% sulphuric acid