Swiss researchers have studied the effects of sound waves on the flavors of cheese, according to a Reuters article. Surprisingly, cheese that listened to A Tribe Called Quest produced the most highly-rated flavors in a blind taste test. How does this test pass or fail the standards of scientific experimentation?
“Nine wheels of Emmental cheese that weighed 10 kilos (22 pounds) each were placed in separate wooden crates last September to test the impact of music on flavor and aroma,” the Reuters article said. Then each wheel of cheese was exposed to a 24-hour loop of a single musical artist via mini-transmitters instead of loudspeakers. Artists included Mozart, Led Zeppelin, A Tribe Called Quest, electronic musicians Vril and Yello, and three ranges of sound frequencies. The ninth wheel was left in silence as a control element to the research. Finally, a culinary jury performed two blind taste tests on each wheel of Emmental and decided that A Tribe Called Quest’s “We Got It from Here” influenced the best aroma and flavor profile in the cheese. The next study will focus exclusively on various hip-hop songs stimulating the cheese. This unusual study offers a great opportunity to explore the scientific method and what the components and practices are for a true scientific experiment.
Testing Sound and Taste – Control and Manipulation
When conducting any scientific experiment, control is the first factor that must be present. “Control means we can prevent outside factors from interfering in the outcome of our study,” said Dr. Amanda M. Rosen, Associate Professor of Politics and International Relations at Webster University. “We do this by using very systematic, set procedures that are followed rigorously, to ensure that the study conditions are the same throughout, and by using a control group in addition to a treatment group.”
A control group is a test subject that receives no interference or treatment. In the Emmental cheese wheel experiment, the control group is the cheese that was exposed to no music at all throughout the experiment. The overall element of control, on the other hand, comes from the researchers using wheels of cheese that are as close to identical as possible—in size, weight, shape, and manufacture—as well as utilizing similar storage conditions and test equipment for each kind of cheese.
The second factor is manipulation. “This means that the researcher has the ability to manipulate the independent variable by administering a treatment,” Dr. Rosen said. For the Swiss researchers, the chief method of manipulation was using mini-transmitters to send sound waves to eight of the nine wheels of cheese in order to affect change in them.
The final two factors of a scientific experiment—a random selection of participants and random assignment to groups—are exactly what they sound like: ensuring a broad and eclectic range of test subjects and not letting the subjects choose whether they will be in a control group or variable group. However, these components mostly apply to human experimentation.
The Problem of Validity in Testing Sound Waves on Taste
Unfortunately, the experiment determining the effects of various sound waves on cheese hits a major speed bump when it comes to validity, or proving that the experiment was a true reflection of its claim due to cause-and-effect. “To be valid, a measure must also be reliable, or give consistent results,” Dr. Rosen said. One could argue that the experiment was conducted eight times, since eight of the cheeses were exposed to various music and produced comparatively different resulting aromas and flavors than one another and the control cheese. However, each cheese was only stimulated by sound waves one time. Repeated trials are necessary to prove the claim.
There are also two kinds of validity: internal validity and external validity. Internal validity involves the process of ensuring that any observed results have been directly caused by the independent variables of a study—the musical stimulation, in this example—and not something external or unrelated to the study, like minute variations in the culinary environments or scientific storage from wheel to wheel.
“External validity refers to the extent to which we can generalize the results we get from the sample we study in our experiment to a wider population,” Dr. Rosen said. The nine wheels of Emmental cheese in the sound wave experiment have likely been eaten, tested, and disposed of. External validity asks if we can apply what we learned about them to wheels of Emmental around the world or if the experiment is only representative of a certain subset, like wheels made at one specific location or from one specific cow.
Further testing is needed to determine if stimulating wheels of cheese with A Tribe Called Quest or other hip-hop will result in fruitier, more aromatic cuisine. For now, this single experiment provides a great example of how to use scientific experiments to unravel the mysteries of the universe, cheesy or otherwise.
Dr. Amanda M. Rosen contributed to this article. Dr. Rosen is an Associate Professor of Politics and International Relations and a fellow in the Institute for Human Rights and Humanitarian Studies at Webster University. She holds a B.A. in Political and Economic Studies of Europe from Duke University as well as an M.A. and a Ph.D. in Political Science from The Ohio State University.