Lesson 21

Lesson 21: Food Preservation (Part I)

Learning Objective

Synthesising the concept of food preservation

Syllabus Correlations

· Theme: Investigating Materials

· Learning Area: Food Preservation

· Learning Objective: Synthesising the concept of food preservation

Learning Outcomes:

Pupils should be able to:

· state what food preservation is;

· describe ways to preserve food;

· give examples of food for each type of food preservation;

· give reasons why each way of food preservation is used.

Concept(s) Introduced:

· ways to preserved food;

· examples of food fro each type of preservation.

Skills Covered:

· Observing, classifying, making inferences, interpreting data, making conclusions, comparing and contrasting.

Vocabulary/ New Words:

· decay, food preservation, drying, boiling, cooling, freezing, salting, bottling, canning, vinegar, pH paper

Value(s) Incorporated:

· Having an interest in and curiosity about the environment.

· Being diligent and persevering.

· Realising that science is a means to understand nature.

· Thinking rationally

· Analysing the things around us

Materials Needed:

-

Point(s) to Note:

Explain and give examples of each type of food preservation.

Teaching Strategies
Set Induction	Show pictures of a few types of food that is perishable and has to be preserved well. Teacher explains to pupils that food is preserved to last longer. Teacher can ask pupils to give some examples on how to preserve food. Then, show some pictures about different types of food preservations, encourage pupils to discuss types of food preservation used. Component: Introduction
Step 1	Play the component. Ask pupils what food preservation is. Explain the definition of food preservation. Ask pupils what is the benefit of food preservation. Explain that it helps to make food last longer. Play the content component. Teacher explains that different types of food require different ways to preserve. Pupils watch the videos in this component. Ask pupils how to preserve pineapple. Explain that pineapple can be preserved by cooling, bottling, canning and drying. Play the content component. Ask pupils what the methods of food preservations are. Play the content component. Teacher introduces drying. Ask pupils what is the process of drying. Explain that water is removed either placing food under the sun or in the oven. Ask pupils of examples of food preserved by drying. Explain that mircroorganisms need water to live and removal of water makes them unable to grow. Play the content component. Teacher introduces boiling or heating. Ask pupils what is the process of boiling or heating. Explain that food is heated at a high temperature. Ask pupils of examples of food preserved by boiling or heating. Explain that mircroorganisms need room temperature to live and high temperature makes them unable to grow. Play the content component. Teacher introduces cooling. Ask pupils what is the process of cooling. Explain that food is cooled at low temperature. Ask pupils of examples of food preserved by cooling. Explain that mircroorganisms need room temperature to live and low temperature makes them unable to grow. Play the content component. Teacher introduces freezing. Ask pupils what is the process of freezing. Explain that food is frozen at or below 0 degree Celcius. Ask pupils of examples of food preserved by cooling. Explain that mircroorganisms need room temperature to live and low temperature makes them unable to grow. Ask pupils to compare whether freezing or cooling is more efficient. Play the content component. Teacher introduces bottling or canning. Ask pupils what is the process of bottling or canning. Explain that food is cooked and all air in bottles and cans is removed. Ask pupils of examples of food preserved by bottling or canning. Explain that sterilisation is involved and food is heated to high temperature. Explain that mircroorganisms need room temperature to live and high temperature makes them unable to grow. Ask pupils what is the benefit of airtight conditions. Play the content component. Teacher introduces salting. Ask pupils what is the process of salting. Explain that salt is the main ingredient. Ask pupils of examples of food preserved by salting. Explain that mircroorganisms cannot survive in highly salted condition. Ask pupils what is the benefit of using salt. Explain that salt draws out moisture from food. Play the content component. Teacher makes a summary of the different ways for preserving food. Play the content component. Ask pupils whether it is possible to preserve food in more than one way. Teacher explains why we need more than one way to preserve food. For example, food needs to be salted first before we can dry them under the sun. Teacher explains how to combine more than one way to preserve food. Teacher gives examples why some food is suitable for certain methods of food preservation, but not all the methods of preservation are suitable for all food. Ask pupils to gather information and give examples of food that is preserved in certain method. Component: Content
Step 2	Play the activity component. Match the types of food preservation correctly. Drag and drop to match the correct answer. Component: Activity
Step 3	There are five questions in this component covering the learning outcomes. Questions 1 to 3 are objective questions. Q4 is a drag and drop activity. Pupils drag and drop the correct answers for the questions. Q5 consists of true or false questions. Pupils need to identify whether the statements are true or false. Use evaluation sheets to assess the pupils’ understanding of this lesson. Component: Evaluation
Step 4	Conduct a study on salt, sugar and vinegar. Help pupils to distinguish the taste between salt, sugar and vinegar. Ask pupils to list food that uses these food preservatives. Explain to pupils how to use salt, sugar and vinegar to help preserve food. Ask pupils to discuss and think how they can preserve food. Component: Extension
Conclusion	Conclude the lesson by playing this component to further reinforce understanding of the lesson. Help pupils to describe ways to preserve food. Give examples of food for each type of food preservation. Emphasise that some methods of food preservation are used because of certain reasons. Component: Summary