Ethanol Production Questions and Answers

Multiple Choice Questions and Answers on Ethanol Production

Question 1 : What are the fermentation conditions for the ethanol production?

  1. pH 6; temperature 35°C
  2. pH 5; temperature 35°C
  3. pH 6; temperature 30°C
  4. pH 5; temperature 30°C

Answer : 2

Question 2 : Which of the following is used for agitation in a fermentor?

  1. Impeller
  2. Baffles
  3. Sparger
  4. All of these

Answer : 1

Question 3 : To maintain aseptic conditions during fermentation which of the following is needed?

  1. Sterilization of fermentor
  2. Sterilization of air supply
  3. Aeration and agitation
  4. All of these

Answer : 4

Question 4 : High ethanol concentration

  1. promotes yeast growth
  2. inhibits yeast growth
  3. promotes bacterial growth
  4. inhibits bacterial growth

Answer : 2

Question 5 : Which of the following microorganisms help in the ethanol production?

  1. Saccharomyces cerevisiae
  2. Zygomonas mobilis
  3. Saccharomyces uvarum
  4. All of these

Answer : 4

Question 6 : After the fermentation is over, ethanol is recovered by

  1. centrifugation
  2. distillation
  3. filtration
  4. cell disintegration

Answer : 2

Question 7 : The Zygomonas has a merit over yeast because

  1. it has more osmotic tolerance to higher sugar concentration
  2. it has high tolerance to ethanol
  3. it has more specific growth rate
  4. all of the above

Answer : 4

Question 8 : Which of the following organism is not used in any of the traditional industrial fermentation?

  1. E. coli
  2. Yeast
  3. Bacillus
  4. Pseudomonas

Answer : 1

Question 9 : How is air supply to the fermentor sterilized?

  1. By heat filtration
  2. Filtration through fibrous material
  3. Filtration through granular material
  4. All of the above

Answer : 4

Question 10 : As the fermentation for the ethanol production is over, the cells are separated to get the biomass of yeast cells that is used

  1. for next fermentation
  2. as single cell protein for animal feed
  3. as manure
  4. all of the above

Answer : 2

Question 11 : The fermentor can be sterilized by

  1. keeping it in the oven
  2. steam under pressure
  3. boiling
  4. all of these

Answer : 2

Question 12 : Candida utilis is used for the fermentation of waste sulphate liquor since it ferments

  1. hexoses only
  2. pentoses only
  3. both hexoses and pentoses
  4. none of these

Answer : 3

Question 13 : Yeast is used in the production of

  1. ethyl alcohol
  2. acetic acid
  3. cheese
  4. curd

Answer : 1

Question 14 : S cerevisiae start producing ethanol within

  1. 10 h
  2. 12 h
  3. 15 h
  4. 24 h

Answer : 2

Question 15 : If starch containing substrates are used for ethanol production, yeast strain can’t be used directly because

  1. it doesn’t contain amylases to hydrolyze starch
  2. starch is not a suitable substrate for the production of ethanol
  3. it is converted to pentose sugar
  4. none of the above

Answer : 1

Question 16 : Which of the following is used to check vortex and to improve aeration efficiency in a fermentor?

  1. Impeller
  2. Baffles
  3. Sparger
  4. All of these

Answer : 2

Question 17 : What are different substrates used for ethanol production?

  1. Starch containing substrate
  2. Juices from sugarcane or molasses or sugar beet
  3. Waste product from wood or processed wood
  4. All of the above

Answer : 4

Question 18 : Which of the following is used for aeration in a fermentor?

  1. Impeller
  2. Baffles
  3. Sparger
  4. All of these

Answer : 3

Question 19 : Ethanol is produced by

  1. continuous fermentation
  2. batch fermentation
  3. both (1) and (2)
  4. none of these

Answer : 3