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 biology respiration in plants fermentation cell respiration living organisms and energy production

During alcoholic fermentation by yeast two molecules of glucose produce.

  1. $2$ molecules of ethanol $+2$ molecules of $CO _{2}$
  2. $4$ molecules of ethanol $+ 4$ molecules of $CO _{2}$
  3. $6$ molecules of ethanol $+ 6$ molecules of $CO _{2}$
  4. $3$ molecules of ethanol $+ 3$ molecules of $CO _{2}$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Alcoholic fermentation is a process of anaerobic respiration in which 2 molecule of glucose is converted to -
4 molecules of ethanol,
4 molecules of carbon dioxide,and
4 ATP.
So, the correct option is '4 molecules of ethanol + 4 molecules of CO$ _2$'.

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production

Which of the following is correct about fermentation?

  1. Bread gets fermented due to formation of lactic acid.
  2. Pulled up appearance of dough is due to production of $CO _2$

  3. Fermentation in muscles produces alcohol

  4. Both A and B
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

During the process of fermentation in the dough, the bacteria and yeast, convert carbohydrates to carbon dioxide resulting in the formation of gas bubbles. The gas bubbles expand inside the dough making it appear larger, which is called leavening. 

So the correct option is 'Pulled up appearance of dough is due to production of $CO _2$'  

Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production
Which of the following describes the significance of fermentation?
(i) Production of alcohol in the brewing industry
(ii) Making of dough in the baking industry
(iii) Curing of tea and tobacco
(iv) Production of vinegar by acetic acid bacteria

  1. (i),(ii) and (iii)

  2. (i),(ii) and (iv)

  3. (i),(iii) and (iv)

  4. (i),(ii),(iii) and (iv)
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
Alcoholic fermentation is used in the brewing industry for the production of various types of beer, whiskey and other wines. 
Carbon dioxide of alcoholic fermentation is used in the baking industry for making the bread spongy. 
Tea and tobacco leaves are curved (or removed of their bitterness) and provided with a fine flavor through fermentation. Vinegar is obtained by the fermentation activity of acetic acid bacteria.
So the correct answer is '(i),(ii),(iii) and (iv)'.
Multiple choice biology life processes in living organisms- part 1 fermentation cell respiration living organisms and energy production

Fermentation by yeast produces

I. Carbon dioxide
II. Oxygen
III. Water
IV. Alcohol

  1. I only

  2. I and II

  3. I, II and III

  4. I, III and IV

  5. I and IV
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Fermentation is a metabolic process occurs in yeast and bacteria. It occurs in the absence of oxygen. The products produced by yeast includes carbon dioxide, water and ethanol. Glycolysis is the first step of fermentation pathways as well which produces pyruvate, however other steps Kreb's cycle etc. does not take place in the absence of oxygen. Hence option D is correct.

This process is extensively used in alcohol industry. 

Multiple choice biology molecular biology fermentation cell respiration living organisms and energy production

Fermentation is conducted by

  1. All bacteria.

  2. All fungi.

  3. Some fungi and some bacteria.

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

Fermentation is the process of anaerobic respiration, which is carried out by some fungi and bacteria. Fermentation also occurs in muscles of higher vertebrates. In these tissues, it is lactic acid fermentation. Fungi and bacteria carry out alcoholic fermentation (yeast).

Multiple choice biology plant growth other plant hormones cytokinins, ethylene and abscisic acid plant hormones

Which combination is used in fruit ripening?

  1. $80$% $C{H} _{4} +20$% ${O} _{2}$
  2. $80$% ${C} _{2}{H} _{4} +20$% $C{O} _{2}$
  3. $80$% $C{O} _{2} +20$% ${C} _{2}{H} _{4}$
  4. $80$% $C{H} _{4} +20$% $C{O} _{2}$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Ethylene is a gaseous plant hormone. It is also called as ripening hormone. It is used externally to accelerate the fruit ripening process. Also during ripening process, controlled amount of carbon dioxide and oxygen is needed. For artificially ripening fruit, 80% C$ _2$H$ _4$ and 20% CO$ _2$ is used.

Thus, the correct answer is option B.

Multiple choice evs eat when you need food poisoning and food preservation methods food spoilage, adulteration and preservation food spoilage and adulteration

Pasteurised milk is______________

  1. Sterile and will not turn sour

  2. Free from pathogenic bacteria

  3. Not free from bacteria

  4. Both A and B
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation
  • Pasteurization is a process of heating food, which is usually a liquid, to a specific temperature for a predefined length of time and then immediately cooling it after it is removed from the heat. 
  • Raw milk is milk from cows, sheep, or goats that has not been pasteurized to kill harmful bacteria. 
  • This raw, unpasteurized milk can carry dangerous bacteria such as Salmonella, E. coli, and Listeria, which are responsible for causing numerous foodborne illnesses.
  •  Pasteurization makes sure milk is safe to drink by killing any bacteria and also helps to prolong its shelf life.
  •  The process of pasteurization involves heating milk to 71.7°C for at least 15 seconds. Once the milk has been heated, it is then cooled very quickly to less than 3°C. 
Multiple choice evs eat when you need food poisoning and food preservation methods food spoilage, adulteration and preservation food spoilage and adulteration

Sterilization by autoclaving is carried out to

  1. Kill bacteria and other pathogens

  2. Kill viruses

  3. Kill bacteria and enzymes

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

Sterilization by autoclaving is carried out to kill bacteria and other pathogens present in the food, equipment, and materials. In this, a pressurized steam is applied with the heat of 121$^0$C for around 15–20 minutes to kill bacteria, spores, and other pathogens.

Thus, the correct answer is 'Kill bacteria and other pathogens.'

Multiple choice evs eat when you need food poisoning and food preservation methods food spoilage, adulteration and preservation food spoilage and adulteration

............. is the process which is used to make something free from bacteria.

  1. Fermentation

  2. Sterlization

  3. Condensation

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Sterilization is a thermal process generally designed to destroy the stores of the bacterium (C. botulinum). As this microorganism can easily be grown under anaerobic condition producing the deadly toxin that causes botulism. So, it requires heating temperature greater than $ 100^{\circ}C $
Multiple choice evs eat when you need food poisoning and food preservation methods food spoilage, adulteration and preservation food spoilage and adulteration

The gas released during fermentation of sugarby yeast cells is

  1. Carbon dioxide

  2. Carbon monoxide

  3. Hydrogen

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

Fermentation is the process of converting complex organic substance into simpler substance with the action of yeast or bacteria. Yeast ferments the sugar into alcohol, carbon dioxide and little energy.

Multiple choice chemistry rocks and minerals coal petroleum non-renewable sources of energy

Anaerobic fermentation is a process which helps in the formation of:

  1. coal gas

  2. natural gas

  3. water gas

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

Natural gas is formed by the action of anaerobic bacteria on the plants or vegetation thousand of years ago.Over the years under high temperature and pressure, methane gets converted to natural gas.