This set of Microbiology Multiple Choice Questions & Answers (MCQs) focuses on “Industrial Uses of Yeasts”.
1. Which among the following are not used as raw materials for alcohol production?
Explanation: Corn, molasses, sugar beets, potatoes, and grapes are some of the common raw materials employed throughout the world for alcohol fermentation.
2. The organism used for alcohol fermentation should have a high tolerance for alcohol.
Explanation: It is imperative that the culture be one that grows vigorously and has a high tolerance for alcohol as well as a capacity for producing a large yield of alcohol.
3. What is the pH required for production of baker’s yeast?
a) 1 to 2
b) 4 to 5
c) 7 to 8
d) 10 to 12
Explanation: In the manufacture of baker’s yeast, the medium is adjusted to an acid pH of 4 to 5, which helps retard bacterial growth.
4. The leavening or rising of dough is due to which of the following gases?
b) carbon dioxide
d) sulphur dioxide
Explanation: The carbon dioxide produced during the fermentation by baker’s yeast is responsible for the leavening or rising of the dough.
5. Which of the following instrument is used for recovery of yeast cells?
c) filter press
d) mash storage
Explanation: The cells are finally recovered on a filter press, small amounts of vegetable oil are added as a plasticizer, and then this mass of cells is molded into blocks.
6. Which of the following product is used as a food condiment?
a) Baker’s yeast
d) Soy sauce
Explanation: Soy Sauce is produced by the yeast Saccharomyces rouxii and is used as a food condiment.
7. Which of the following yeast can be used to produce microbial protein?
a) Saccharomyces cerevisiae
b) Candida milleri
c) Eremothecium ashbyi
d) Candida utilis
Explanation: Candida utilis is yeast used for producing microbial protein which is used as an animal food supplement (single-cell protein) from paper-pulp waste.
8. The medium for production of Baker’s yeast contains only molasses and inoculum.
Explanation: In the manufacture of baker’s yeast the “stock” strain is inoculated into a medium which frequently contains molasses and corn-steep liquor.
Sanfoundry Global Education & Learning Series – Microbiology.
To practice all areas of Microbiology, here is complete set of 1000+ Multiple Choice Questions and Answers.