Science General · Chemistry

Food Processing and Storage

2,542 Questions

Food processing and storage principles focus on preservation techniques, packaging methods, and preventing microbial contamination. These topics are essential for general science sections in various competitive examinations. Questions explore pasteurization, canning, chemical preservation, and safe food handling practices.

Food preservation methodsPasteurization techniquesFood packaging materialsMicrobial contamination preventionCryopreservation concepts

Food Processing and Storage Questions

Multiple choice physics option b: engineering physics conversion of heat into work: heat engine and it's efficiency engines and cycles refrigerators and heat pumps

Refrigerators and freezers works by:

  1. Converting hot air to cold air

  2. Keeping hot air out with cold air pressure

  3. Removing heat from inside themselves

  4. Blowing cold inside them

  5. Producing cold air
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A gas refrigerant or sometimes air is key to refrigeration in freezers.
The gas refrigerant goes into the compressor and the process of compression makes the gas hot. That hot gas moves through the system getting colder and colder. By the time it reaches the valve – and is pushed through the very small opening – it has turned into a cold mist. 

As the mist goes through the coils under the freezer compartment, it starts to evaporate and turn back into a gas. This evaporation process takes the heat from the freezer compartment with it and as the refrigerant starts to warm up, it is sent back to the compressor to start the process all over again. Eventually the process is completed and there is no heat left in the freezer meaning that all objects in the freezer are frozen.

Multiple choice physics option b: engineering physics conversion of heat into work: heat engine and it's efficiency engines and cycles refrigerators and heat pumps

What is the function of the evaporator in a refrigerator?

  1. The evaporator supplies the heat to the substance, which is to be cooled.

  2. The evaporator absorbs the heat from the atmosphere.

  3. The evaporator absorbs the heat from the substance, which is to be cooled.

  4. Both a and b
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Evaporator is an important component together with other major components in a refrigeration system such as compressor, condenser and expansion device. The reason for refrigeration is to remove heat from air, water or other substance.

It is here that the liquid refrigerant is expanded and evaporated. It acts as a heat exchanger that transfers heat from the substance being cooled to a boiling temperature.
Multiple choice physics option b: engineering physics conversion of heat into work: heat engine and it's efficiency engines and cycles refrigerators and heat pumps

The freezer in a refrigerator is located at the top section so that;

  1. The entire chamber of the refrigerator is cooled quickly due to convection

  2. The motor is not heated

  3. The heat gained from the environment is high

  4. The heat gained from the environment is low
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The freezer in a refrigerator is located at the top section so that the entire chamber of the refrigerator is cooled quickly due to convection.  
The correct option is A.

Multiple choice

HTST is a ________

  1. Genetic Marker in Holstein Cattle

  2. Milking parlor design

  3. Breed of dairy cow

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

HTST stands for High-Temperature Short-Time, which is a common method of pasteurization used in the dairy industry to ensure milk safety by heating it to a specific temperature for a short duration.

Multiple choice

Time/temperature control, safety foods include:

  1. Milk and dairy products

  2. Cut melons

  3. Raw seed sprouts and soy products

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

TCS (Time/Temperature Control for Safety) foods include dairy, cut melons, sprouts, and soy products because they support rapid bacterial growth.

Multiple choice

When receiving food, which of the following is not a reason for rejecting food:

  1. Frozen food is thawed or partly thawed

  2. There is visible mold or slime

  3. Receiving TCS Food at 5 Celcius or 41 Fo

  4. Packaging is damaged or dirty
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

When receiving TCS foods at 5°C (41°F) or below is CORRECT and acceptable. Foods should be rejected if: thawed/partially thawed frozen foods, visible mold/slime, damaged/dirty packaging, or temperatures above safety thresholds. Receiving at proper temperature is good.

Multiple choice

Which of the following is not a safe method to thaw food:

  1. At ambient temperature ( ordinary room temperature)

  2. In a refrigerator unit at 5 celcius ( 41 Fo ) or cooler

  3. Submerged under running potable (drinking quality) water at 21 celcius, (70

  4. As part of the cooking process
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Thawing food at room temperature is unsafe because it allows the outer layers of the food to enter the temperature danger zone while the inside remains frozen, promoting bacterial growth.

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

Which of the following group of preservatives prevent fat/oil containing food from developing a foul smell?

  1. Flavourants

  2. Colorants

  3. Sweeteners

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

Antioxidants prevent or slow down the oxidation of fat/oil which otherwise go rancid to emit a foul odor. This they are used as preservatives in oil or fat containing food.

So, the correct option is 'Antioxidants'.

Multiple choice chemistry chemical reactions effects of oxidation reactions in daily life corrosion of metals electroplating and its application

Which of the following is/are true regarding rancidity?

  1. On keeping for long time, the oxidation of oils and fats, changes the taste and odour of food.

  2. To prevent rancidity, food is stored in air tight containers.

  3. Rancidity can also be prevented by addition of antioxidants.

  4. To prevent rancidity, packed food items are flushed with an inert gas like nitrogen.
Reveal answer Fill a bubble to check yourself
A,B,C,D Correct answer
Explanation

The following are true regarding rancidity. On keeping for long time, the oxidation of oils and fats, changes the taste and odor of food and makes them unfit for consumption. To prevent rancidity, food is stored in air tight containers. Rancidity can also be prevented by addition of antioxidants. To prevent rancidity, packed food items are flushed with an inert gas like nitrogen.

Multiple choice chemistry metals effects of oxidation reactions in daily life corrosion of metals electroplating and its application

The term used to indicate the development of unpleasant smell and taste in fat and oil-containing foods due to aerial oxidation is:

  1. acidity

  2. radioactivity

  3. rabidity

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

The term used to indicate the development of unpleasant smell and taste in fat and oil containing foods due to aerial oxidation is rancidity.
The process of oxidizing fatty and oily substances is called as rancidity.

Multiple choice chemistry metals effects of oxidation reactions in daily life corrosion of metals electroplating and its application

Rancidity can be prevented by -

  1. adding anti-oxidants

  2. packing oily food in nitrogen gas

  3. packing oily food in argon gas

  4. use of spices
Reveal answer Fill a bubble to check yourself
A,B,D Correct answer
Explanation

Rancidity is decomposition of oils, fats and lipids. It normally happens when food items are stored for a long time and gets exposed to oxygen.. Rancidity can be prevented by adding anti-oxidants, vacuum packing, replacing air by nitrogen, refrigeration of the food-stuff or packaging of food items in airtight containers.

Multiple choice chemistry changes around us effects of oxidation reactions in daily life corrosion of metals electroplating and its application

If edible oil is allowed to stand for a long time in an iron or tin container, the oil becomes rancid.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

If edible oil is allowed to stand for a long time in an iron or tin container the fatty acids in the oil react with rust flakes or powder to form salts. These salts contaminate the oil and hence the oil becomes rancid. Thus the above statement is true.