National Agricultural Literacy Curriculum Matrix
FoodMASTER Middle: Eggs
6 - 8
Two 1-hour activities
Students will learn the anatomy of eggs and the concept of forming colloidal dispersions called foams as they learn the anatomy of an egg, create a foam by whisking egg whites, investigate the effect of whisking time on foam, and compare and contrast the effect of different substances on the stability of foam.
- Foaming Bonds student handout, 1 per student
- Foam Formulations student lab sheet, 1 per student
- Extraordinary Eggs student handout, 1 per student
Part A, per group of 4-5 students:
- 1 egg
- 1 egg separator
- 2 small glass or steel bowls
- 1 whisk
- 1 paper plate
- 1 kitchen timer or stopwatch
Part B, per group of 4-5 students:
- Assigned treatment. One of the following treatments pre measured and placed in a small cup
- 1 cup of egg whites
- 1 tsp. sugar
- ¼ tsp. salt
- ¼ Tbsp. acid (cream of tartar or lemon juice)
- ¼ tsp. vegetable oil (or any type)
- Note: Because there are 4 different treatments, multiple groups may be using the same treatment. Amounts above reflect what is needed for 1 group – adjust according. The plastic cups may be used to provide groups with their treatment.
- 1 funnel
- 1/8 cup (2 tablespoons) of egg white
- 1 small glass or steel bowl
- 1 rubber spatula
- 1 whisk or electric mixer
- 1 ruler
- 1 kitchen timer or stopwatch
- 1 10- or 25-mL graduated cylinder
- measuring spoons (teaspoon, ½ teaspoon, ¼ teaspoon, ½ tablespoon)
Essential Files (maps, charts, pictures, or documents)
- Extraordinary Eggs teacher key
- Extraordinary Eggs student handout
- Foaming Bonds teacher key
- Foaming Bonds student handout
- Foam Formulations teacher key
- Foam Formulations lab sheet
colloidial dispersions: a substance in which particles are evenly dispersed within a medium (e.g. milk, because milk proteins and fat are dispersed in water)
foams: a frothy mass of tiny bubbles formed from a liquid, such as egg whites
solutions: a homogenous mixture in which one substance is dissolved in another
Did you know? (Ag Facts)
- To tell if an egg is raw or hard-boiled, spin it! If the egg spins easily, it is hard-boiled but if it wobbles, it is raw.1
- The color of an eggshell is purely dependent on the breed of the hen.2
- Worldwide, around 1.2 trillion eggs are produced for eating every year. The average person consumes 173 eggs per year.2
Background Agricultural Connections
Interest Approach – Engagement
- Show students a picture of lemon meringue pie. Ask, "What is the primary ingredient of the meringue in this pie?" Use guiding questions if necessary to lead students to recognize that meringue is made from egg whites.
- Ask, "Is it a chemical change or a physical change that transforms an egg white into the foam of a meringue?"
- Instruct students to define (or quickly research) the terms "foam" and "colloidal dispersion." Once the terms have been defined, ask how the terms can be related to eggs.
- Review information found in the Background Agricultural Connections section of the lesson, lesson Procedures, and the attached Essential Files.
- Prepare materials for each group.
- For Part B, assign each student group a treatment (sugar, acid, fat, or salt).
- Prepare materials for treatment assignments. You are encouraged to allow students to measure out their own treatments; but if time is a concern, pre-measuring treatments is recommended.
- Egg White: 6 clear cups containing 1/8 cup of egg white
- Treatment A: 2 clear cups containing 1 teaspoon sugar
- Treatment B: 2 clear cups containing ¼ tablespoon (1/2 tsp. + 1/4 tsp.) acid (cream of tartar or lemon juice)
- Treatment C: 2 clear cups containing ¼ teaspoon fat (oil – any type)
- Treatment D: 2 clear cups containing ¼ teaspoon salt
- Separate the egg yolk and white ahead of time if you do not want students to participate in this portion of the lab. For Part B, you may also choose to use a carton of egg whites versus separating raw eggs.
- Frequent hand washing is an important emphasis in egg lab activities. Students should be discouraged from tasting raw egg (including foams). When practicing appropriate food safety procedures, eggs can be safely handled in the classroom.
- Timesaver: If feasible, students should use an electric mixer versus a whisk, particularly if time is a concern.
- Important Note: If you choose to separate the egg yolk and white to obtain the egg white needed for Part B, make sure the egg yolk does not contaminate the egg whites. Additionally, make sure no oils contaminate the bowl or beater. These factors can negatively impact the formation of egg whites during the investigation.
Lab: Foam Formulations
- Before beginning the lab investigation:
- Require students to wash their hands.
- For food safety reasons, DO NOT allow students to taste any egg products. When practicing appropriate food safety procedures, eggs can be safely handled in the classroom.
- Emphasize the importance of practicing good food safety behaviors by not consuming substances used as part of the lab investigation.
- Give each student one copy of Foaming Bonds and ask them to read the handout and complete the focus questions for this lab investigation.
- Distribute lab materials. It is recommended that materials are organized into stations for easier distribution. Students should be arranged in small groups of 4-5. Each group should receive the lab supplies outlined in the Materials section as well as 1 copy of the Foam Formulations lab sheet.
- Launch Part A of the lab by asking students to make a prediction about actions that can be taken to increase the stability (firmness) of egg white foams.
- Show students the Egg Cracking Demonstration Video. The video will demonstrate how to properly crack an egg and separate the white from the yolk.
- Next, show students the Foam Formulations Part A Video which will illustrate the four stages of peak formation in egg whites. The photographs found beginning on page 9 of the Student Demonstration Slideshow for illustration.
- Throughout Part A of this lab investigation, students will observe the parts of an egg and the different stages of foam formation in egg whites. This part of the lab will provide a foundation for Part B, when students observe how various substances impact foam formation.
- Allow students to work in small groups on the Foam Formulations lab sheet to complete Part A. After completing initial observations and conclusions, students should be prepared to begin Part B.
- Launch Part B of the lab by distributing the lab supplies outlined in the Materials section of the lesson. It is recommended that materials are organized into stations for easier distribution. Students should still be arranged in small groups of 4-5.
- Provide students with their assigned treatments. Students will predict what will happen to their egg white’s stability when their assigned treatment is added. Photographs demonstrating each treatment (before and after) are included in the Student Demonstration Slideshow.
- Sugar: When sugar is added to an egg white at the foamy stage it will create a smooth, stable foam. However, the addition of the sugar will delay denaturation of the egg proteins, increasing the beating time required to reach peak foam stage. Sugar is best added to egg whites in the beginning stages of foam formation.
- Acid: An egg white’s natural pH is basic (7.6 to 7.9). When an acid is added, it will decrease the pH of the egg white. Proteins are less stable and more prone to denaturation at lower pH levels. The denaturation of the egg proteins will improve foam formation; however, adding too much acid (pH less than 4.6) will result in delayed foam formation and decreased stability.
- Fat: Fat will cause a decrease in the stability of egg white foam. Even a small amount will interfere with formation of a foam. For this reason, the egg yolk cannot mix with egg white when making foams. The fat in the egg yolk will prevent the formation of foam
- Salt: Salt is often added to egg foams because it adds flavor. The addition of salt will decrease the stability of egg white foams if eggs are only beaten for a short time. If eggs are beaten for an extended amount of time, salt will not have an effect of the stability of the foam.
- Demonstrate how to measure the foam height or show students the Lab III: Foam Formulations Part B Video.
- Allow students to work in small groups to finish the Foam Formulations lab sheet.
- Follow-up with a class discussion about the impact of various substances on proteins.
Investigating Your Health Activity: Extraordinary Eggs
- Instruct students to research eggs and their health and/or nutritional benefits prior to beginning the activity.
- Using the information provided in the Background Agricultural Connections section of the lesson or information learned from researching eggs, students should examine the nutrition profile for brown and white eggs and egg whites and egg yolks.
- Students can find the nutrition profile of eggs by accessing the USDA’s FoodData Central, or by using the labels provided.
- If you choose to use the provided egg nutrition information, see the attached teacher key for answers to the Investigating Your Health lab questions. Answers to questions should be similar despite the food label source used.
- If completed in-class, allow students to work in small groups on the handout to further explore the topic and respond to questions.
- Follow-up with a class discussion about student findings related to the health benefits of eggs.
Concept Elaboration and Evaluation
After conducting these activities, review and summarize the following key concepts:
- Eggs provide a source of high quality and relatively inexpensive protein to our diet.
- Eggs are produced on farms, mostly by female chickens (hens) in the United States.
- Eggs can be consumed in many ways including such as scrambling, boiling, or frying. They may also be used as an important ingredient to many baked and processed foods.
We welcome your feedback! Please take a minute to tell us how to make this lesson better or to give us a few gold stars!
Use egg white to make meringue cookies.
Use other types of foods to investigate emulsions (i.e. milk).
Investigate the impact of temperature (cold versus warm) on the formation of foams.
Investigate emulsifiers (see Chapter 10: Fats Lab Investigation II Examining Emulsions).
Suggested Companion Resources
- All About Eggs (Multimedia)
- Eat Happy Project video series (Multimedia)
- Eggs 101: A Video Project (Multimedia)
- Virtual Egg Farm Field Trips (Multimedia)
- The Science of Cooking (Website)
Agricultural Literacy Outcomes
Food, Health, and Lifestyle
- Evaluate food labels to determine food sources that meet nutritional needs (T3.6-8.b)
- Identify agricultural products (foods) that provide valuable nutrients for a balanced diet (T3.6-8.g)
- Identify sources of agricultural products that provide food, fuel, clothing, shelter, medical, and other non-food products for their community, state, and/or nation (T3.6-8.i)
Education Content Standards
MS-LS1 From Molecules to Organisms: Structures and Processes
MS-LS1-7Develop a model to describe how food is rearranged through chemical reactions forming new molecules that support growth and/or release energy as this matter moves through an organism.
MS-PS1: Matter and Its Interactions
MS-PS1-2Analyze and interpret data on the properties of substances before and after the substances interact to determine if a chemical reaction has occurred.
Common Core Connections
Reading: Anchor Standards
CCSS.ELA-LITERACY.CCRA.R.1Read closely to determine what the text says explicitly and to make logical inferences from it; cite specific textual evidence when writing or speaking to support conclusions drawn from the text.
CCSS.ELA-LITERACY.CCRA.R.10Read and comprehend complex literary and informational texts independently and proficiently.
CCSS.ELA-LITERACY.CCRA.R.3Analyze how and why individuals, events, or ideas develop and interact over the course of a text.
CCSS.ELA-LITERACY.CCRA.R.4Interpret words and phrases as they are used in a text, including determining technical, connotative, and figurative meanings, and analyze how specific word choices shape meaning or tone.
CCSS.ELA-LITERACY.CCRA.R.7Integrate and evaluate content presented in diverse media and formats, including visually and quantitatively, as well as in words.
Speaking and Listening: Anchor Standards
CCSS.ELA-LITERACY.CCRA.SL.1Prepare for and participate effectively in a range of conversations and collaborations with diverse partners, building on others’ ideas and expressing their own clearly and persuasively.
Language: Anchor Standards
CCSS.ELA-LITERACY.CCRA.L.1Demonstrate command of the conventions of standard English grammar and usage when writing or speaking.
Writing: Anchor Standards
CCSS.ELA-LITERACY.CCRA.W.2Write informative/explanatory texts to examine and convey complex ideas and information clearly and accurately through the effective selection, organization, and analysis of content.
CCSS.ELA-LITERACY.CCRA.W.7Conduct short as well as more sustained research projects based on focused questions, demonstrating understanding of the subject under investigation.
CCSS.ELA-LITERACY.CCRA.W.9Draw evidence from literary or informational texts to support analysis, reflection, and research.