The Internet belongs to everyone. Let’s keep it that way.

Protect Net Neutrality
Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


Heat Transfer and Methods of Cooking

No description

Purply Pink

on 1 November 2017

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of Heat Transfer and Methods of Cooking

By the end of this chapter, you will be able to:
- explain the reasons for cooking food;
- describe the different types of heat transfer
(conduction, convection and radiation) during cooking;
- state the advantages and disadvantages of each
method of cooking;
- prepare healthy, varied and interesting meals using a
combination of cooking methods.

Learning Outcomes

Cooking kills microorganisms in raw food
(e.g. as raw meat).
It destroys toxins in food

1) Makes food safe for consumption

What are the reasons
for cooking food?

E.g. Cooked rice grains become light and fluffy

Cooking softens food (e.g. rice and vegetables).

2) Makes food easier to chew,
swallow and digest

3) Improves the flavour
and appearance of food

E.g. Food ingredients can be combined to produce tasty
food products such as biscuits

Cooking makes food taste and look
more appetising

4) Adds variety to the diet

Boiling of seafood (steamboat)

Food can be cooked and presented in many
different ways
(e.g. fish can be steamed, boiled or grilled).

Grilled fish
Steamed fish
5) Makes food last longer

Cooking delays food spoilage by destroying
the enzymes and microorganisms in food
(e.g. heat-treated milk last longer than
raw milk).

Flavour / taste

How does cooking
changes food?

Raw State
Cooked state
2) Convection

1) Conduction

3) Radiation

How is heat transferred to food during cooking?


Food is cooked as heat is continuously
transferred to the base of the frying pan
(e.g. of cooking method is pan frying).

Heat causes the molecules in the metal
frying pan to vibrate, producing heat.

Heat produced by the molecules is transferred to the food which is in direct contact with the frying pan.


cooler portion sinks

hotter portion rises

As the liquid heats up, hotter portion rises, and cooler portion sinks, forming convection currents (e.g. of cooking methods are baking and boiling).

Heat is transferred through the
movement of a fluid (liquid or gas).


Radiation waves

When infrared rays fall on the food, heat is absorbed and the food gets cooked (e.g. of cooking methods are grilling and microwave cooking).

Heat energy travels from one point to
another through infrared rays

Dry-heat Cooking

Heat is transferred to food through
conduction, convection and radiation.

Examples of dry-heat cooking are:




Food is cooked by applying
dry heat directly to it.

Moist-heat Cooking

Examples of moist-heat cooking are:




Food is cooked either in boiling
water or steam, usually at 100̊C.

Heat is transferred to food through
convection and conduction.



Other methods

Examples of modern cooking are:

Food can be cooked easily and do not require
constant supervision.

Heat is transferred through
convection and radiation.



Heat is transferred
through convection.


How can food be cooked by combining the different
methods of cooking?

Food can be cooked using more than
one method of cooking.

Using different methods to cook a food or
dish can improve its:
Hot-fat Cooking


or sautéing

Examples of hot-fat cooking are:

Heat is transferred to food through conduction
and convection.


Food is cooked in heated oil
or fat (180-205̊C).


Switch on your laptop
Full transcript