Can You Get Enough Protein from Milk Alternatives?
Grades: Grades 9-10
Author: Dori L. Hess
Source: This material is based upon work supported by the National Science Foundation under Grant No. EEC-1161732. Got Protein Kit by Bio-Rad: http://www.bio-rad.com/webroot/web/pdf/lse/literature/10006836A.pdf. The Bio Rad Experiment is an ideal extension of this lab or for Honors/Advanced Biology Courses. The lesson listed here is an inexpensive way for students to make a simple quantitative analysis of protein in foods, without using a spectrophotometer and protein assay equipment. The lesson is ideal to do with introductory biology students.
This guided inquiry lesson allows students to apply their knowledge of organic compounds (primarily proteins) to their everyday life. Biochemistry lessons on proteins and enzyme insufficiency often make students wonder how someone who is lactose intolerant can obtain essential proteins from milk alternatives. This lesson lets students explore whether or not milk alternatives have the same protein concentration as traditional milk.
What should students know as a result of this lesson?
- Proteins are an essential biopolymers for organisms
- Proteins can be found in many foods, other than meats
What should the students be able to do as a result of this lesson?
- Students should be able to read nutrient labels and understand the importance of them
- Students should be able to recognize the importance of proteins in their diet
- Students will recognize that milk alternatives can be a healthy choice
- Various types of milk: coconut, almond, soy, traditional milk, etc.
- Spot plates
- Protein test strips: parameter 2 urinalysis strips are the least expensive ones
While there are various routes that can be taken to engage students for this lesson, it is suggested that a classroom discussion is used to begin creative thinking on the part of the students. A few suggestions for topics could be:
- Some say that milk is not a healthy choice anymore, but it contains vital proteins. Do you think that milk alternatives can/will provide an equivalent amount of protein?
- If people drink milk to get their protein, what do lactose intolerant people drink?
- Lacto/ovo vegans do not drink milk and they don’t eat meat, do they get an adequate supply of protein from milk alternatives?
Depending on which route you take, it is suggested that you precede the discussion with an article or short video clip. Below are a few video suggestions:
Review Lab Safety Procedures
Students can apply classroom content to everyday life
Students are bombarded with information and often times don’t understand the significance of a lesson in school. This easy, hands on activity provides students with the opportunity to evaluate a situation, form a hypothesis, check their hypothesis and then compare their results to nutrition labels.
- Body builders like to take in adequate quantities of casein (which is found in milk) yet some people try to avoid casein. After conducting the experiment and testing milk products for protein concentrations, students could research which alternatives have/don’t have casein in them
- Students can conduct this test on eggs and egg alternatives, as well as other foods.
- Assign scenarios to groups, have students conduct the lesson and then present their findings to the class. Scenarios could include:
- Group 1: People who are lactose intolerant can/can’t get protein from milk substitutes
- Group 2: People who are lacto/ovo vegans do not get adequate protein from milk alternatives
- Group 3: People who are lacto/ovo vegan do/ do not get protein from egg substitutes
- Group 4: Students can compare protein content in various protein drinks
- Group 5: Students can compare protein concentration of several types of eggs (white eggs, brown eggs, double yolk eggs)
- Understanding of protein structure and function in the human body
- Why are proteins needed to maintain homeostasis?
Best Teaching Practices
- Scientific Literacy
- Hands on/minds on learning
- Real life situations and problem solving
- Issue based Learning
Alignment with Standards
- RST.11-12.9. Synthesize information from a range of sources (e.g., texts, experiments, simulations) into a coherent understanding of a process, phenomenon, or concept, resolving conflicting information when possible. (HS-ETS1-1),(HS-ETS1-3)
- HS-LS1-2. Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms.
- SCIENCE INQUIRY AND APPLICATION - During the years of grades 9 through 12, all students must use the following scientific processes with appropriate laboratory safety techniques to construct their knowledge and understanding in all science content areas:
- Identify questions and concepts that guide scientific investigations
- Design and conduct scientific investigations
- Use technology and mathematics to improve investigations and communications
- Formulate and revise explanations and models using logic and evidence (critical thinking)
- Recognize and analyze explanations and models; and communicate and support a scientific argument
Structure and function of proteins
How dietary proteins play a role in maintaining homeostasis
Proper lab safety procedures should be reviewed prior to the lesson
Do not drink any of the milk substitutes
Biopolymers, Nutrition, Food Science
Teachers may choose various routes to assess their students. Traditional assessments could include: Lab Report or Student presentation on the lab and their results.
http://mccam.weebly.com/lactase-lab-rubric.html This is an online rubric that can easily be used for this lab.
Grouping Suggestions: Students can conduct this activity individually or in groups of two. If students conduct the lesson in groups, ensure that each partner has a specific role.
Pacing/Suggested Time: Suggested time: 90 minute block: 1 to 2 class periods; 45 minute classes: Day 1 - Reading/video and discussion, Day 2 - activity and compile results, Day 3 - present findings (if classroom presentations are used)
Do not let students look at nutrient labels prior to forming their hypothesis or obtaining lab results, this may create bias.
If eggs are used, please note that 1 gram of egg = 1 ml (Bio Rad ).
Choose the engagement scenario that will fit the needs of your students.
Printable PDF Worksheets