Vinegar and Citric Acid – Section 1

1. 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

Correct Answer: B. a fed-batch reactor can be used to maintain low ethanol concentrations

2. 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 sulfate

Correct Answer: B. precipitate calcium citrate

3. Which of the following microorganism is used for the production of citric acid?

A. Lactobacillus bulgaricus
B. Saccharomyces cerevisiae
C. Aspergillus niger
D. Streptococcus lactis

Correct Answer: C. Aspergillus niger

4. Sugar content of the fermentation medium for citric acid is maintained at

A. 10-15%
B. 15-20%
C. 20-25 %
D. 25-30 %

Correct Answer: C. 20-25 %

5. Spirit vinegar is produced from

A. fruit juices
B. malted grain
C. ethanol
D. ale

Correct Answer: C. ethanol

Leave A Comment?

nine + seventeen =