Multiple Choice Questions and Answers on Ethanol Production
Question 1 : What are the fermentation conditions for the ethanol production?
- pH 6; temperature 35°C
- pH 5; temperature 35°C
- pH 6; temperature 30°C
- pH 5; temperature 30°C
Answer : 2
Question 2 : Which of the following is used for agitation in a fermentor?
- Impeller
- Baffles
- Sparger
- All of these
Answer : 1
Question 3 : To maintain aseptic conditions during fermentation which of the following is needed?
- Sterilization of fermentor
- Sterilization of air supply
- Aeration and agitation
- All of these
Answer : 4
Question 4 : High ethanol concentration
- promotes yeast growth
- inhibits yeast growth
- promotes bacterial growth
- inhibits bacterial growth
Answer : 2
Question 5 : Which of the following microorganisms help in the ethanol production?
- Saccharomyces cerevisiae
- Zygomonas mobilis
- Saccharomyces uvarum
- All of these
Answer : 4
Question 6 : After the fermentation is over, ethanol is recovered by
- centrifugation
- distillation
- filtration
- cell disintegration
Answer : 2
Question 7 : The Zygomonas has a merit over yeast because
- it has more osmotic tolerance to higher sugar concentration
- it has high tolerance to ethanol
- it has more specific growth rate
- all of the above
Answer : 4
Question 8 : Which of the following organism is not used in any of the traditional industrial fermentation?
- E. coli
- Yeast
- Bacillus
- Pseudomonas
Answer : 1
Question 9 : How is air supply to the fermentor sterilized?
- By heat filtration
- Filtration through fibrous material
- Filtration through granular material
- 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
- for next fermentation
- as single cell protein for animal feed
- as manure
- all of the above
Answer : 2
Question 11 : The fermentor can be sterilized by
- keeping it in the oven
- steam under pressure
- boiling
- all of these
Answer : 2
Question 12 : Candida utilis is used for the fermentation of waste sulphate liquor since it ferments
- hexoses only
- pentoses only
- both hexoses and pentoses
- none of these
Answer : 3
Question 13 : Yeast is used in the production of
- ethyl alcohol
- acetic acid
- cheese
- curd
Answer : 1
Question 14 : S cerevisiae start producing ethanol within
- 10 h
- 12 h
- 15 h
- 24 h
Answer : 2
Question 15 : If starch containing substrates are used for ethanol production, yeast strain can’t be used directly because
- it doesn’t contain amylases to hydrolyze starch
- starch is not a suitable substrate for the production of ethanol
- it is converted to pentose sugar
- 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?
- Impeller
- Baffles
- Sparger
- All of these
Answer : 2
Question 17 : What are different substrates used for ethanol production?
- Starch containing substrate
- Juices from sugarcane or molasses or sugar beet
- Waste product from wood or processed wood
- All of the above
Answer : 4
Question 18 : Which of the following is used for aeration in a fermentor?
- Impeller
- Baffles
- Sparger
- All of these
Answer : 3
Question 19 : Ethanol is produced by
- continuous fermentation
- batch fermentation
- both (1) and (2)
- none of these
Answer : 3