Download Lesson 1B - Grass vs Grain

Course Title: Food Technology & Safety
Lesson Title: Analyzing grass fed versus grain fed beef experiments
TEKS Addressed in Lesson: 130.13 C 1B, 1C, 2A, 2B, 6B
Lesson Objectives: The student will be able to:
1. Compare and contrast nutritional values of grass fed beef and grain fed beef using
the scientific method in writing with no errors;
2. Describe the different tastes of grass fed beef and grain fed beef using the scientific
method in writing with no errors;
3. Compare the cost differences of grass fed beef and grain fed beef using the
scientific method in writing with no errors.
Tools and Equipment
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Handout: Class results of scientific method
Handouts: Grass fed vs. grain fed ground beef info
Handout: The scientific method
Toothpicks
Napkins
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1 lb. cooked sirloin grass fed beef
1 lb. cooked sirloin grain fed beef
(If a food lab is available these two meats can be cooked in class for a lab exercise)
(If grass fed steak is unavailable in your area you can substitute steak for ground beef)
Key Terms / Vocabulary
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Scientific Method
Fat Content
Protein Content
Calories
Interest Approach/Anticipatory Set
1. Link: How many of you have heard advertisements on TV or the radio or seen ads
at the store advertising for organic meats and grass fed beef? What do they always
say about grass fed beef?
2. Motivation: Most of us have probably never had the chance to taste grass fed beef
because it’s too expensive or we don’t really feel like venturing out and trying
something new, but today we are going to have the opportunity to actually taste it
and look into the nutritional details of grass fed beef.
3. Today we are going to use the scientific method to analyze the cost, nutritional
value, and taste of both grass fed beef and grain fed beef.
Teaching Plan and Strategy / Presentation of New Material
1. Give the scientific method handout to the students.
2. Go over the six steps of the scientific method and ask for feedback from the students on what
they believe each step means and what action is required during each step.
3. Once you are finished going through the 6 steps direct the students attention to the Step 1 of
the scientific method.
4. Ask them to give ideas of what the three things they think we are going to test.
5. Question 1: Does grain fed beef or grass fed beef have a higher caloric value and total grams of
fat per serving?
6. Question 2: Does grain fed beef or grass fed beef taste better?
7. Question 3: Does grass fed beef or grain fed beef cost more per lb. at the store?
8. Move on to step 2. Background research. Ask the students to share what they know and what
their personal opinions are about each of the three questions asked in step 1. Instruct them to
write their results down on the handout.
9. Move on to step 3. Construct a hypothesis. Based on the questions in step 1 and the research in
step 2 have each student propose a hypothesis and write their proposition on the handout.
10. Move on to step 4. Test your hypothesis by doing an experiment.
11. To test hypothesis 1 give the students the handout and have them compare the nutritional
values of the two products. Ask the students to share their finding aloud and to describe
whether they were shocked or not by their findings.
12. To test hypothesis 2 give each student a meatball that has one toothpick in it and have them
taste it. Then give them a meatball with two toothpicks in it. Have them document which one
they believe tasted better. Then share that the meatballs with one toothpick are grass fed and
the ones with two are grain fed. Ask the students to share their thoughts on the tastes of the
two afterwards.
13. To test hypothesis 3 use the same handout that was used to test hypothesis 1. Have the
students compare the two products and write down the results. Ask the students to share their
thoughts on the findings.
14. Move on to step 5. Analyze your data and make a conclusion. Instruct the students to look at
their three hypotheses and the results of each. Then have them make a brief conclusion based
on what they see or observed during experimentation
Activity/Application/ Student Engagement /Laboratory
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Move on to step 6. Report your findings.
Hand each student a class finding worksheet.
Going off of the worksheet have students tally the results.
Q: How many people thought grain fed beef would have had more calories and a
higher fat content?
5. Have students tally results on worksheet.
6. Q: How many people thought grass fed beef would have had more calories and a
higher fat content?
7. Have students tally results on worksheet.
8. Q: How many people predicted that grain fed beef would have tasted better?
Tally results.
9. Q: How many people predicted that grass fed beef would have tasted better?
Tally results.
10. Q: How many people actually thought that grain fed beef tasted better?
Tally results.
11. Q: How many people actually thought that grass fed beef tasted better?
Tally results.
12. Q: How many people predicted that grain fed beef would have cost more?
Tally results.
13. Q: How many people predicted that grass fed beef would have cost more?
Tally results.
Evaluation / Summary
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Does grass fed beef cost more or less?
About how much more?
Does grass fed beef have a higher caloric value? Grams of fat?
A math worksheet that includes STEM integration accompanies this lesson
College & Career Readiness Standard
Science 1 B 1, 10 A 3
Name:___________________
Date:____________________
Teacher:________________
Food Technology & Safety
Grass vs. Grain Activity – YOU do the Math
Use your cost and nutrition handouts to answer questions 1 - 4.
1. If the average family was to eat 30lbs of rib-eye steaks a year, would it be cheaper to eat grassfed or grain-fed beef?
2. How much cheaper would it be?
3. Suppose you were to eat an 8oz sirloin each week for an entire year, how many calories would
you consume for that year from the sirloin?
4. How many grams of fat would you consume in a year if you were to eat one organic grass fed
beef steak each week for a year?
Developed for the Educational Excellence project
Department of Agricultural Leadership, Education, and Communications
Texas A&M University
©Texas Education Agency, 2011