Ethanol Production

Q1: To maintain aseptic conditions during fermentation which of the following is needed?

A Sterilization of fermentor

B Sterilization of air supply

C Aeration and agitation

D All of these

ANS:D - All of these

No answer description is available.

Q2: How is air supply to the fermentor sterilized?

A By heat filtration

B Filtration through fibrous material

C Filtration through granular material

D All of the above

ANS:D - All of the above

No answer description is available.

Q3: Which of the following is used for agitation in a fermentor?

A Impeller

B Baffles

C Sparger

D All of these

ANS:A - Impeller

No answer description is available.

Q4: After the fermentation is over, ethanol is recovered by

A centrifugation

B distillation

C filtration

D cell disintegration

ANS:B - distillation

No answer description is available.

Q5: S cerevisiae start producing ethanol with in

A 10 h

B 12 h

C 15 h

D 24 h

ANS:B - 12 h

No answer description is available.

Q6: The Zygomonas has a merit over yeast because

A it has more osmotic tolerance to higher sugar concentration

B it has high tolerance to ethanol

C it has more specific growth rate

D all of the above

ANS:D - all of the above

No answer description is available.

Q7: Which of the following is used to check vortex and to improve aeration efficiency in a fermentor?

A Impeller

B Baffles

C Sparger

D All of these

ANS:B - Baffles

What the reason behind the use of baffles?

Q8: 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

ANS:B - pH 5; temperature 35°C

No answer description is available.

Q9: High ethanol concentration

A promotes yeast growth

B inhibits yeast growth

C promotes bacterial growth

D inhibits bacterial growth

ANS:B - inhibits yeast growth

No answer description is available.

Q10: The fermentor can be sterilized by

A keeping it in the oven

B steam under pressure

C boiling

D all of these

ANS:B - steam under pressure

No answer description is available.

Q11: Which of the following organism is not used in any of the traditional industrial fermentation?

A E. coli

B Yeast

C Bacillus

D Pseudomonas

ANS:A - E. coli

No answer description is available.

Q12: 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

ANS:C - both hexoses and pentoses

No answer description is available.

Q13: As the fermentation for the ethanol production is over, the cells are separated to get the biomass of yeast cells that is used

A for next fermentation

B as single cell protein for animal feed

C as manure

D all of the above

ANS:B - as single cell protein for animal feed

No answer description is available.

Q14: If starch containing substrates are used for ethanol production, yeast strain can't be used directly because

A it doesn't contain amylases to hydrolyze starch

B starch is not a suitable substrate for the production of ethanol

C it is converted to pentose sugar

D none of the above

ANS:A - it doesn't contain amylases to hydrolyze starch

Starch contains many complex glucose units, so yeast can't takeup the starch directly inorder to consume so it should broke down the starch into glucose units by using amylase enzyme.

Q15: Ethanol is produced by

A continuous fermentation

B batch fermentation

C both (a) and (b)

D none of these

ANS:C - both (a) and (b)

Ethanol is produced by continuous fermentation. In Brazil, which was the largest exporter of ethanol, they use sugarcane, however in countries like the USA they use corn. Corn is far cheaper to grow than sugarcane, however Brazilian farmers say that they get more than twice as much ethanol per hector to what cornn can. America but a tarrif on american sourced sugarcane based ethanol because of the domestic modity prices. This is double the price of corn based ethanol.

Q16: 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

ANS:D - All of the above

No answer description is available.

Q17: Which of the following is used for aeration in a fermentor?

A Impeller

B Baffles

C Sparger

D All of these

ANS:C - Sparger

No answer description is available.

Q18: Which of the following microorganisms help in the ethanol production?

A Saccharomyces cerevisiae

B Zygomonas mobilis

C Saccharomyces uvarum

D All of these

ANS:D - All of these

No answer description is available.

Q19: Yeast is used in the production of

A ethyl alcohol

B acetic acid

C cheese

D curd

ANS:A - ethyl alcohol

No answer description is available.



img not found
img

For help Students Orientation
Mcqs Questions

One stop destination for examination, preparation, recruitment, and more. Specially designed online test to solve all your preparation worries. Go wherever you want to and practice whenever you want, using the online test platform.