Too Much Sodium?
Have you ever noticed that some people shake a lot of salt on their food while others prefer none at all? Penn State University conducted a study to try to understand why some people like more salt than others and found that genetics plays a significant role in determining how much salt people like. Those who prefer more salt have more sensitive taste buds and are known as “supertasters”.
Will people in the same family have similar saltiness preferences? Does age make a difference? Using a simple experiment with toast, unsalted butter and salt, you can find out!
How salty do people prefer their food?
- Three sticks of unsalted butter
- Table salt
- Butter knife
- Measuring spoons
- Three small mixing bowls
- Three stirring spoons
- Notebook and pen
- Set your three sticks of unsalted butter on the counter until they are room temperature. This may take a couple of hours.
- Place one stick of butter in each of the three small mixing bowls.
- Add no salt to the first bowl, ½ teaspoon of salt to the second and a full teaspoon of salt to the third. Stir the two bowls with added salt, mixing thoroughly.
- Gather five people willing to participate in your experiment.
- Toast a slice of bread for each subject. Slice the bread lengthwise into three strips. Add butter from each dish to one strip of the toast. Be sure to keep your toast strips in order, so you know which is which, but do not tell the participant how salty the butter is.
- Which butter type do you think the participant will enjoy the most? Why? Use this time to write down your hypothesis, your best guess about what you think is going to happen.
- Give each of your participants their toast pieces. Ask your participants to report which piece of toast they liked best. Record your results, and compare them to your hypothesis.
- If you want, you can test more participants to observe if people from the same family have similar butter preferences.
35% of women and 15% of men are supertasters, so only one or two people from your study should have preferred the saltiest butter.
25% of people overall are supertasters and are very sensitive to bitterness and sweetness. That’s why they tend to prefer more salt—the salty flavor can help mask those flavors that they’re sensitive to. Another 25% of people are not overly sensitive to any particular flavor at all. The other 50% of people have taste profiles that fall somewhere in the middle.
How much of your daily recommended intake of sodium is in a teaspoon of salt? Do you think supertasters are at a greater risk of eating too much sodium? It might be fun to find out how much of each type of butter it would hypothetically take to reach 100% of your daily recommended sodium intake!
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