Biology

Microorganisms in Food Production

1,120 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

Which of the following organisms are acellular?

  1. Virus

  2. Bacteria

  3. Fungi

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

Acellular organisms are those that are not composed of cells. They are different from other cellular organisms as they cannot divide, and they lack the ability to synthesize proteins. For example: virus.

Multiple choice

The process of conversion of sugar into alcohol is called

  1. nitrogen fixation

  2. moulding

  3. fermentation

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

Fermentation is the process of converting carbohydrates to alcohol or organic acids using microorganisms—yeasts or bacteria—under anaerobic conditions.

Multiple choice

The products of anaerobic respiration in yeast is _______.

  1. oxygen

  2. lactic acid

  3. ethyl alcohol

  4. water and energy
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In the absence of oxygen, yeast performs fermentation. This process converts glucose into ethyl alcohol (ethanol), carbon dioxide, and a small amount of energy.

Multiple choice

Yeast is used for

  1. uptake of nutrition

  2. food manufacturing

  3. disease resistance

  4. disease prevention

  5. -
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yeast is used for baking and making alcoholic beverages. It has been used in this way since ancient times.

Multiple choice

Which of the following enzymes are derived from the fungus Aspergillus niger?

  1. Penicillin amidase, Pectinase, β-glucanase

  2. Lactase, Rennin, Penicillin amidase

  3. Glucoamylase, β-glucanase, Penicillin amidase

  4. Lactase, Rennin, Pectinase

  5. Glucoamylase, Pectinase, β-glucanase
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Glucoamylase: Aspergillus niger , Rhizopus spp. Pectinase: Aspergillus niger  β-glucanase: Aspergillus niger, Bacillus subtilis All the three can be obtained from Aspergillus niger.

Multiple choice

Match the following sauerkraut defects for their causative agents

P. Soft kraut 1. Due to growth of bacteria, mold and/or yeast
Q. Slimy kraut 2. Due to surface growth of Torula yeast
R. Rotted kraut 3. Bacterial growth does not initiate till last stage
S. Pink kraut 4. Rapid growth of Lactobacillus cucumens and L, plantarum specially at elevated temperature

  1. P – 4, Q – 2, R – 3, S – 1

  2. P – 3, Q – 4, R – 1, S – 2

  3. P – 1, Q – 3, R – 2, S – 4

  4. P – 2, Q – 1, R – 4, S – 3
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Soft kraut (P-4) is caused by rapid fermentation at high temperatures. Slimy kraut (Q-2) is due to Torula yeast. Rotted kraut (R-3) is due to delayed bacterial initiation. Pink kraut (S-1) is due to yeast/mold growth.

Multiple choice biology the respiratory system anaerobic respiration in organisms anaerobic and aerobic respiration cellular respiration

When you add yeast to dough, it rises because

  1. Yeast cells reproduce by budding

  2. Budding yeast cells form colonies

  3. Of the bulk of the new yeast cells

  4. The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

  • The yeast changes the sugar in the dough into carbon dioxide gas and ethanol (alcohol).
  •  The gas, trapped in the dough, makes it rise; the alcohol produced during fermentation evaporates during baking. Hence, When you add yeast to the dough, it rises because the rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration.
So, the correct answer is 'The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration'.

Multiple choice biology the respiratory system anaerobic respiration in organisms anaerobic and aerobic respiration cellular respiration

When you add yeast to dough, it rises because

  1. Yeast cells reproduce by budding.

  2. Budding yeast cells form colonies.

  3. The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration.

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Yeast are the organism that executes the process of fermentation in which they break down the sugar into its simpler forms for obtaining energy. In this process carbon dioxide and alcohol are also forms and CO$ _2$ helps the dough to rise. The process is favorable in humid and warm conditions in colder environment it slows down.

So, the correct answer is 'The rapidly reproducing yeast cells release carbon dioxide due to anaerobic respiration'.