Biology

Microorganisms in Food Production

1,086 Questions

Microorganisms play a vital role in food production through processes like fermentation and bioprocessing. Questions on this topic cover the use of yeast, bacteria, and industrial microbiology. These concepts are important for science sections in various competitive exams.

Alcoholic fermentationDairy beverage productionIndustrial ethanol preparationCitric acid productionBiodigester temperature

Microorganisms in Food Production Questions

Multiple choice botany biotechnology and its applications biotechnological regulations pcr asexual modes of reproduction

If the fermentation of molasses during the manufacturing of ethyl alcohol is delayed then the conclusion that can drawn is

  1. Molasses is diluted

  2. Molasses is not diluted

  3. More yeast is added

  4. Temperature is maintained around 410 K
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
  • The sugarcane molasses are generally used as the fermentation medium. 
  • The yeast cells are grown in this medium to perform anaerobic respiration which produces ethanol and carbon dioxide. 
  • The molasses which are used is diluted so that the activity of yeast cells is fast and the production of ethanol occurs at a rapid pace. 
  • If the process is slowed down, then the molasses must not have been diluted before the addition of the fermentation medium in the fermentor.
  • Thus, the correct answer is option B. 
Multiple choice chemistry surface chemistry enzyme catalysis catalysis proteins and enzymes

In a fermentation tank, molasses solution is mixed with yeast enzymes. After three days alcohol was observed. The speed of the reaction in this case is:

  1. slow

  2. medium

  3. fast

  4. very fast
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The maximum concentration of alcohol possible through a natural fermentation is about $12\%$ ethanol,

after this the alcohol concentration fatal for yeast and it can't survive, that's why after some time the speed of the reaction is slow.

Multiple choice bio-chemistry biological oxidation oxidative phosphorylation living organisms and energy production glycolysis
All of the following processes can release ${CO} _{2}$ except

  1. Alcoholic fermentation

  2. Oxidative decarboxylation and Krebs' cycle

  3. Oxidative phosphorylation
  4. Conversion of $\alpha$-ketoglutaric acid to succinic acid
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The process of oxidative phosphorylation involves the production of ATP by utilizing electrons falling from the hydrogen in glucose to the oxygen in a living cell. It does not lead to the production of carbon dioxide molecules.

Thus, the correct answer is 'Oxidative phosphorylation.'

Multiple choice

Which grain is commonly used in brewing beer and is known for its malting process?

  1. Wheat

  2. Rice

  3. Corn

  4. Barley
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Barley is a cereal grain commonly used in brewing beer. It undergoes a malting process, where it is soaked, germinated, and dried to produce malt, a key ingredient in beer production.

Multiple choice

What is the term used for the process of fermenting food using microorganisms such as bacteria or yeast?

  1. Pickling

  2. Smoking

  3. Curing

  4. Fermentation
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fermentation is a culinary technique that involves using microorganisms such as bacteria or yeast to convert carbohydrates into alcohol or acids, creating unique flavors and textures in food.

Multiple choice

What is the scientific name of the most commonly used yeast in baking?

  1. Saccharomyces cerevisiae

  2. Candida albicans

  3. Aspergillus niger

  4. Rhizopus stolonifer
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Saccharomyces cerevisiae is a species of yeast commonly known as baker's yeast or active dry yeast. It is widely used in baking and fermentation industries due to its ability to convert sugars into carbon dioxide and alcohol.

Multiple choice

Which process is primarily responsible for the rising of dough in bread making?

  1. Photosynthesis

  2. Fermentation

  3. Respiration

  4. Transpiration
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fermentation is the process by which yeast converts sugars into carbon dioxide and alcohol. In bread making, the carbon dioxide produced during fermentation causes the dough to rise, resulting in a light and airy texture.

Multiple choice

What is the primary sugar that yeast consumes during fermentation?

  1. Sucrose

  2. Glucose

  3. Fructose

  4. Lactose
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Glucose is the primary sugar that yeast consumes during fermentation. It is a simple sugar that is easily broken down by yeast enzymes, resulting in the production of carbon dioxide and alcohol.

Multiple choice

Which gas is produced by yeast during fermentation?

  1. Oxygen

  2. Carbon dioxide

  3. Nitrogen

  4. Hydrogen
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Carbon dioxide is the gas produced by yeast during fermentation. It is released as a byproduct of the conversion of sugars into alcohol and is responsible for the rising of dough in bread making and the carbonation of alcoholic beverages.

Multiple choice

What is the primary alcohol produced by yeast during fermentation?

  1. Ethanol

  2. Methanol

  3. Propanol

  4. Butanol
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ethanol is the primary alcohol produced by yeast during fermentation. It is a type of alcohol that is commonly found in alcoholic beverages such as beer, wine, and spirits.

Multiple choice

What is the role of yeast in the production of alcoholic beverages?

  1. It converts sugars into carbon dioxide and water.

  2. It converts sugars into carbon dioxide and alcohol.

  3. It converts sugars into oxygen and water.

  4. It converts sugars into oxygen and alcohol.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yeast plays a crucial role in the production of alcoholic beverages by converting sugars into carbon dioxide and alcohol through the process of fermentation. This process is responsible for the characteristic flavors and aromas of alcoholic beverages.

Multiple choice

What is the process of converting sugars into alcohol and carbon dioxide by yeast called?

  1. Photosynthesis

  2. Respiration

  3. Fermentation

  4. Transpiration
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fermentation is the process by which yeast converts sugars into alcohol and carbon dioxide. This process is widely used in the production of alcoholic beverages, bread, and other fermented foods.

Multiple choice

What is the role of yeast in the production of bread?

  1. It provides nutrients for the bread.

  2. It gives bread its characteristic flavor.

  3. It causes the dough to rise.

  4. It adds color to the bread.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Yeast plays a crucial role in the production of bread by causing the dough to rise. During fermentation, yeast consumes sugars in the dough and produces carbon dioxide gas as a byproduct. This gas creates bubbles in the dough, causing it to expand and rise.

Multiple choice

What is the recommended amount of yeast to use for 1 pound of flour in bread making?

  1. 1 teaspoon

  2. 2 teaspoons

  3. 3 teaspoons

  4. 4 teaspoons
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The recommended amount of yeast to use for 1 pound of flour in bread making is typically 2 teaspoons. This amount can vary depending on the type of yeast used and the desired rising time.

Multiple choice

What are some common signs that yeast is no longer active?

  1. The yeast has a strong, pungent odor.

  2. The yeast has a grayish or brownish color.

  3. The yeast does not foam when mixed with warm water.

  4. The yeast has a slimy or watery texture.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

One of the common signs that yeast is no longer active is that it does not foam when mixed with warm water. Active yeast should produce a foamy layer on the surface of the water when mixed.