Taste Tests and Other Science Projects with Volunteers
Certain kinds of science questions require input from volunteers. Whether the project involves a taste test or another kind of test, volunteers can be a key component for projects exploring human behavior and perception, human biology, or food sciences.
Sometimes, a science project is all about you and the experiment. You have a question. You have a set of variables. You have a hypothesis. You have a procedure, and by following the steps, you will see what happens, make observations, and analyze your data to see if your hypothesis is supported by your experiment. Your results won't be subject to human behavior. Instead, you will watch what happens between your variables, observe and gather data, and draw conclusions. Some projects go that way.
But some projects require the human factor. For some projects, you need test subjects (or volunteers). You need to know what people think, or do, or like, or see, or how they behave in certain scenarios because your science question and hypothesis has to do with taste, or human behavior, or human memory or perception, or something else that you will analyze based on how people respond to the test you are running.
A taste test is a classic example of one kind of scientific testing situation in which a set of volunteers who can offer feedback on different recipes or techniques may be helpful. Maybe you are exploring gluten-free alternatives or lower-carb or even sugar-free solutions. Or maybe you are experimenting with the difference in preparation methods like chilling cookie dough before baking it compared to baking it immediately after mixing. Evaluating different formulations for homemade lip gloss might involve similar testing.
Keep in mind that many science fairs require quantitative rather than qualitative results. So a science project on cheesecake methods may involve gathering data about the final cheesecake's texture or surface when made different ways rather than simply asking which one tastes better. Similarly, a comparison of the use of different amounts of baking powder in quick breads can be quantitatively compared by measuring the height of corn muffins made from different recipes instead of simply running a taste test. (A taste test might be useful, however, to see if changing ingredient amounts or ratios "also" changes the taste.) But for some projects and science questions, answering your question may require data gathered from human subjects. (Note: Be sure and get permission to use human subjects before beginning any science project.)
Some projects may require testing of groups of people in an effort to draw conclusions about how people in certain groups (e.g., of different ages, gender, or location) respond to something. Exploring questions about human behavior and cognitive development, for example, may require that you run a hands-on test to compare how children of different ages approach something conceptual. The Piaget's Theory of Conservation: When One Cup of Water is Less Than One Cup of Water project is a great example of this kind of science investigation. Similarly, while the Stroop Effect will give you plenty to consider in terms of the human brain, what happens if you look at the Stroop Effect in terms of a person's age?
If working with human subject testing sounds intriguing, the following science project ideas may be of interest or may kickstart your thinking about something else you might want to test with your science fair project this year:
- Sweet as Sugar: Comparing the Sweetness of Sugar & Sugar Substitutes: sugar substitutes all taste different, and the amount needed to reach a desired "sweetness" varies. Put sugar substitutes to a taste test to see how sweeteners compare to sugar. [See Sweet Like Sugar? Weekly Science Activity Spotlight for a family-friendly version of this experiment using homemade lemonade.]
- It's Written All Over Your Face: The Science of Facial Expressions: investigate to see if people can accurately read how someone is feeling by looking at their facial expression.
- Do You Have the Willpower to Taste Something Sour?: do our taste buds change with age? Experiment with a sour taste test to find out!
- Enjoy It Now... Or Enjoy It Later? Understanding Delayed Gratification: perform a classic marshmallow experiment to see how children of different ages respond to the promise of delayed gratification.
- Are Childproof Containers Really Childproof?: containers for medicines and products that may be harmful if swallowed or even touched by children are designed to make it more difficult for someone to accidentally open them (or difficult for children to open at all). With a group of volunteers, you can explore whether or not these strategies work.
- How Do You Make the 'Best' Cookie?: experiment with different techniques for baking cookies and evaluate the success of each based on a taste test.
- Piaget's Theory of Conservation: When One Cup of Water is Less Than One Cup of Water: try a classic child development project to better understand how and when children develop an understanding of certain abstract concepts.
- 'They're Not Sticking!' A Study of Gender Responses to Frustration: do stereotypes about how girls and boys do things bother you? In this experiment, put stereotypes regarding frustration to a hands-on test.
- What Conflicting Mental Tasks Reveal About Thinking: The Stroop Effect: see the Stroop Effect in action, but think about the testing you are doing. Do certain groups of people respond differently or get less tripped up by the Stroop Effect?
- Measuring Your Taste Threshold: how do different groups respond to things that are salty, sour, or sweet. Are there certain characteristics of a volunteer that seem related to how sensitive someone is to certain tastes?
- Pretty Packaging: Can Attractive Packaging Lead to Healthier Eating?: some parents dye veggies fun colors to encourage kids to eat them. Can the way you package or present a food also determine whether or not someone eats it? (You might get creative and take this kind of exploration in a whole new direction with a look at bento boxes!) [See What Shape is a Hard-boiled Egg? for related ideas and a fun project using hard boiled eggs in unusual shapes.]
- What's in a Face? Are Composite Faces More Attractive than Real Faces?: what makes one face attractive and another less so? Are there features that are universally viewed as attractive? How do these ideals measure up to the faces of real people?
- That's a Pretty Tough Baby! A Study of Gender Stereotypes in Children: how early do children start to pick up on and perpetuate gender stereotypes? Though other variables come into play (like where you live), this project offers an interesting look at the development of social perception in children.
- That's a Real Smile! ...or is it?: how well can people "read" other people by looking at a smile? Can people really offer a fake smile and have it pass by unnoticed, or can most people spot the differences between real and fake smiles?
- Potions and Lotions: Lessons in Cosmetic Chemistry: explore the chemistry of making lip balm and test batches made with different ingredients to see which people prefer.
- Picture This: How Visualizing Data Can Lead to the Right (or Wrong) Conclusion: use volunteers to evaluate how different methods of portraying data can lead to people misunderstanding the data and/or drawing incorrect conclusions.
- Hands-on Shopping: More Likely to Buy if You Can Give It a Try?: explore whether being able to hold a product before you buy it makes a difference in how the product is perceived and whether or not someone makes a purchase.
- The Brains Behind 'Where's Waldo?': set up a fun visual puzzle and test volunteers to explore the relationship between the number of distracters in the puzzle and how hard it is to locate the target in the puzzle.
- Shimmy, Shimmy Soda Pop: Develop Your Own Soda Pop Recipe: creating your own custom soda recipe by experimenting with the amount of calcium bicarbonate and the resulting degree of carbonation is a fun hands-on food science project. You can easily add in a taste test component to get feedback from volunteers on the fizz factor (and other qualities) of each formula you test.
- Do You Love the Taste of Food? Find Out if You Are a Supertaster!: you will need volunteers willing to show off their tongues for this science project, but with a group of willing participants, you can take a colorful and closeup look at taste buds on the tongue and make correlations between the number of papillae and how a person experiences food.
Record the Details
With a group of volunteers, there are many angles you can explore related to a science question, but make sure you are diligent about recording your data and recording information about each volunteer in your lab notebook. Noting categories like age and gender for each volunteer, for example, may be very important in analyzing your data, but there are numerous categories that may be relevant. Carefully tracking this kind of information about your volunteers may also open up new ways to analyze your data that you had not initially considered at the beginning of your project.
Check the Rules and Talk with a Teacher
Before beginning a project that involves human subjects, be sure and check with your teacher (or check science fair guidelines for your local fair) about experiments involving human subjects. Fairs affiliated with Intel International Science and Engineering Fair (ISEF), for example, may require an Informed Consent Form (permission sheet) from each participant. Refer to these Science Buddies documents for more information: Projects Involving Human Subjects and Scientific Review Committee.
For a look at a different kind of "survey"-based science project, see Survey Science: Asking Questions and Analyzing Answers to Test a Hypothesis.