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This section includes 86 Mcqs, each offering curated multiple-choice questions to sharpen your Biotechnology knowledge and support exam preparation. Choose a topic below to get started.
51. |
Sugar content of the fermentation medium for citric acid is maintained at |
A. | 10-15% |
B. | 15-20% |
C. | 20-25 % |
D. | 25-30 % |
Answer» D. 25-30 % | |
52. |
What are the fermentation conditions for the ethanol production? |
A. | pH 6; temperature 35°C |
B. | pH 5; temperature 35°C |
C. | pH 6; temperature 30°C |
D. | pH 5; temperature 30°C |
Answer» C. pH 6; temperature 30°C | |
53. |
Sodium or potassium meta bi sulphate is added to crushed grapes to |
A. | enhance the flavouring compound |
B. | check the undesirable organisms |
C. | maintain pH |
D. | all of the above |
Answer» C. maintain pH | |
54. |
The crystal-like material sometimes found in wine bottles is |
A. | residual diatomaceous earth |
B. | tannin |
C. | prevented by cold stabilizing |
D. | caused by excessive malic acid |
Answer» D. caused by excessive malic acid | |
55. |
Sake is |
A. | rice beer or wine of India |
B. | wheat beer or wine |
C. | barley beer or wine |
D. | rice beer or wine of Japan |
Answer» E. | |
56. |
The germination of barley kernels under controlled temperature and humidity to generate enzymes for the degradation of starch and protein is known as |
A. | brewing |
B. | malting |
C. | mashing |
D. | pitching |
Answer» C. mashing | |
57. |
The organism used for the preparation of sonti is |
A. | Rhizopus sonti |
B. | Aspergillus oryzae |
C. | Lactobacillus vermiformis |
D. | Saccharomyces pyriformis |
Answer» B. Aspergillus oryzae | |
58. |
Grist is |
A. | coarse powder obtained after milling of malted barley |
B. | an aqueous extract of malt |
C. | malted barley |
D. | coagulated protein obtained during boiling |
Answer» B. an aqueous extract of malt | |
59. |
The fermentor can be sterilized by |
A. | keeping it in the oven |
B. | steam under pressure |
C. | boiling |
D. | all of these |
Answer» C. boiling | |
60. |
The organism used for the preparation of sake is |
A. | Rhizopus sonti |
B. | Aspergillus oryzae |
C. | Lactobacillus vermiformis |
D. | Saccharomyces pyriformis |
Answer» C. Lactobacillus vermiformis | |
61. |
Sherry is a type of |
A. | wine |
B. | beer |
C. | brandy |
D. | none of these |
Answer» B. beer | |
62. |
The dried malt is the source of |
A. | amylase |
B. | proteinases |
C. | both (a) and (b) |
D. | cellulase |
Answer» D. cellulase | |
63. |
Sonti is |
A. | rice beer or wine of India |
B. | wheat beer or wine |
C. | barley beer or wine |
D. | rice beer or wine of Japan |
Answer» B. wheat beer or wine | |
64. |
The process of making malt as soluble as possible by using enzymes adjuncts etc is known as |
A. | brewing |
B. | malting |
C. | mashing |
D. | pitching |
Answer» D. pitching | |
65. |
After the fermentation is over, ethanol is recovered by |
A. | centrifugation |
B. | distillation |
C. | filtration |
D. | cell disintegration |
Answer» C. filtration | |
66. |
Which of the following organism is used for the fermentation of grapes? |
A. | Rhizopus sonti |
B. | Aspergillus oryzae |
C. | Lactobacillus vermiformis |
D. | Saccharomyces cerevisiae |
Answer» E. | |
67. |
In liquid surface culture process for the fermentation to produce citric acid, |
A. | A. niger is used with solid substrate as sweet potato |
B. | A. niger floats on the surface of solution |
C. | Fungal mycelium grows through out the solution in a deep tank |
D. | both (a) and (b) |
Answer» C. Fungal mycelium grows through out the solution in a deep tank | |
68. |
What temperature is maintained during anaerobic fermentation of white wine? |
A. | 10-21 °C |
B. | 21-30 °C |
C. | 30-35 °C |
D. | 15-25 °C |
Answer» B. 21-30 °C | |
69. |
Ethanol is oxidized to acetic acid aerobically using |
A. | Acetobacter |
B. | Gluconobacter |
C. | both (a) and (b) |
D. | Lactobacillus |
Answer» D. Lactobacillus | |
70. |
What is the pH of the medium when molasses is used as substrate for the production of citric acid? |
A. | 3 |
B. | 4 |
C. | 5 |
D. | 6 |
Answer» D. 6 | |
71. |
For the recovery of citric acid after fermentation, Ca(OH)2 is added to the slurry to |
A. | precipitate calcium carbonate |
B. | precipitate calcium citrate |
C. | precipitate calcium phosphate |
D. | precipitate calcium sulphate |
Answer» C. precipitate calcium phosphate | |
72. |
What temperature is maintained during anaerobic fermentation of red wine? |
A. | 20-24 °C |
B. | 24-27 °C |
C. | 27-31 °C |
D. | 31-34 °C |
Answer» C. 27-31 °C | |
73. |
Which of the following is used for aeration in a fermentor? |
A. | Impeller |
B. | Baffles |
C. | Sparger |
D. | All of these |
Answer» D. All of these | |
74. |
Vinegar is typically produced in fed batch reactors because |
A. | a fed batch reactor can be used to maintain low acetic acid concentrations |
B. | a fed batch reactor can be used to maintain low ethanol concentrations |
C. | acetic acid bacteria tend to ferment at high ethanol concentrations |
D. | all of the above |
Answer» C. acetic acid bacteria tend to ferment at high ethanol concentrations | |
75. |
Malolactic fermentation |
A. | produces lactic acid |
B. | reduces total acidity |
C. | produces diacetyl |
D. | all of these |
Answer» E. | |
76. |
Which is not the purpose of punching down? |
A. | To oxidize the wine |
B. | To extract tannin |
C. | To reduce possible microbial spoilage |
D. | To keep the cap moist |
Answer» B. To extract tannin | |
77. |
Candida utilis is used for the fermentation of waste sulphate liquor since it ferments |
A. | hexoses only |
B. | pentoses only |
C. | both hexoses and pentoses |
D. | none of these |
Answer» D. none of these | |
78. |
Which type of press produces the most high quality juice or wine? |
A. | Membrane press |
B. | Continuous press |
C. | Vertical basket press |
D. | Horizontal basket press |
Answer» B. Continuous press | |
79. |
Wine yeast |
A. | is sensitive to sulphur di oxide |
B. | is resistant to sulphur di oxide |
C. | shows enhanced enzyme production in presence of sulphur di oxide |
D. | none of the above |
Answer» C. shows enhanced enzyme production in presence of sulphur di oxide | |
80. |
What are different substrates used for ethanol production? |
A. | Starch containing substrate |
B. | Juices from sugarcane or molasses or sugar beet |
C. | Waste product from wood or processed wood |
D. | All of the above |
Answer» E. | |
81. |
Maturation of the beers is carried out at |
A. | 14°C |
B. | 10°C |
C. | 6°C |
D. | 2°C |
Answer» E. | |
82. |
The yeast generated during the fermentation of beer is generally separated by |
A. | centrifugation |
B. | filtration |
C. | cell disruption |
D. | all of these |
Answer» B. filtration | |
83. |
Final alcohol content in wine varies from |
A. | 6-9 % by weight |
B. | 8-13 % by weight |
C. | both (a) and (b) |
D. | 13-15 % by weight |
Answer» D. 13-15 % by weight | |
84. |
What is the desirable sugar content of the grapes required for the wine production? |
A. | 2-5% |
B. | 5-10% |
C. | 10-14% |
D. | 14-20% |
Answer» E. | |
85. |
Bock beer is prepared from |
A. | roasted germinated barley seeds |
B. | rice |
C. | wheat |
D. | grapes |
Answer» B. rice | |
86. |
Which of the following is true for the ale beer? |
A. | Top yeast of S cerevisiae is used |
B. | Fermentation is quick and completes in 5-7 days |
C. | Quantity of hops used is more than in lager beer |
D. | All of the above |
Answer» E. | |