Kitchen Science: The Many Uses of Corn
When in the kitchen with your child, preparing a meal or snack, opportunities to initiate conversations about scientific topics are too numerous to count. Are you cooking corn – corn on the cob, popcorn, frozen or canned corn? If you are using a cooking oil – is it made from corn? Thinking about corn is fascinating on so many levels, I barely know where to begin.
Scientists make observations and look for patterns.
If you are having corn for dinner, in any of its many forms, invite your child to take a close look. Corn on the cob perhaps makes the most sense as a starting point for learning about corn, as it represents how corn grows. Take a look at the corncob or ear before it is shucked. Once those outer leaves are removed, what can you see? What are those threads or silk? What purpose might they serve? (The silk threads capture pollen for germination. Each thread of silk develops from a single kernel, and each kernel must be pollinated to fill the ear. If there are gaps or missing kernels, they failed to pollinate. Each thread of silk sticks out of the top of the corn husk and waves in the wind capturing pollen. That pollen then travels down the silk to the kernel.)
If you don’t have corn on the cob available, frozen corn kernels and popcorn kernels are also interesting to examine. Regardless, keep the conversations going. Each time you have corn for dinner, as a side vegetable, in a salsa, or perhaps even as cornmeal baked into cornbread, you can keep the process of guided discovery going.
As always, a magnifying glass will reveal the secrets of those kernels and the cob. Invite your child to look closely, describing what she sees. Find the language to capture the color, texture, and smell of corn. What does it sound like when shucking an ear of corn? Encourage use of all the senses when observing. Write (you or your child) those descriptive words representing observations in a journal or capture those perceptions when drawing. If tasting corn, find language to describe the experience. Corn varieties are labeled as sweet or buttery. What other terms describe how they taste?
If you have an opportunity to visit a cornfield and your child can see a stalk up close, this experience will be incredibly helpful in understanding where corn comes from. Invite your child to get up close and inspect the leaves and stalk. Take time to examine how the leaves are connected to the stalk and how the ear grows out of the stalk. While you are in the cornfield take a look at the soil. What does it look like? Are there critters on the stalks or on the ears of corn (i.e., worms or other insects)?
Can you tell if there are other animals (besides us) are interested in consuming the corn? What other animals might also like to have corn as their meal?
Compare and Contrast
There are many varieties of corn grown globally and their differences are worth noting. To make comparisons, your child can start with your next trip to the grocery store. Can your child determine if there are different types of corn sold? If you are lucky, in the fresh vegetable section of your supermarket you may have white corn, yellow corn or bicolor corn (yellow and white kernels mixed together). In the canned vegetable section, invite your child to examine the cans of corn. What differences can your child detect (color and size are obvious, but listen up for more interesting comparisons such as references to sweet corn, baby corn, or dried corn)?
Around Thanksgiving, there are ornamental corn varieties for sale. These are usually dried, but the color combinations are worth a closer examination. Can you find blue popcorn kernels? Examine any or all of these kernels that you can find. If you don’t want to purchase them, perhaps you can take a quick look in a store. The topic of corn can be highlighted and expanded on all year long!
Corn kernels are seeds. Compare kernels with other seeds you can find in your kitchen (cucumber, tomatoes, or fruit are all likely candidates). What are seeds and what differences among those seeds can your child notice?
For a broader perspective on different types of corn, perhaps visit a seed store and examine the packets of corn seed available. What differences does your child notice? Note the colors corn can come in (yellow, white, red, blue, brown, purple and even black).
Alternatively, take a look on-line. Here is a site with images of the different varieties or ornamental corns: https://www.harrisseeds.com/storefront/s-106-corn-seeds-ornamental-corn.aspx
It is not the same as touching or smelling, but looking at these images, what does your child notice? What differences are apparent?
So far we have mostly been talking about corn as you would recognize it as a side vegetable with lunch or dinner. Invite your child to look in your kitchen for corn in other forms (corn oil, corn starch, corn meal, corn syrup, polenta, hominy). Count how many other things that corn is used to make.
Can he think of other uses of corn (as feed for animals, as used in ethanol, in biodegradable products, insulation materials, packing materials, paint and explosives!)? If he can’t identify other products, perhaps you can drop hints. Between 60% and 40% of the corn grown in this country is used to feed livestock, ensuring quality meat, dairy products, and eggs. There are so many uses for this amazing plant!
If you are visiting a cornfield, compare the heights of the plants. Or if you have a cornfield nearby, note the changing heights of the plants over the spring and summer as they mature and grow.
Compare popcorn kernels and the popped versions. Can you still see the kernel in the popped version? Popcorn apparently comes in two shapes labeled snowflake or mushroom. Snowflake popcorn is what most of us think of as what we eat when at the movies. These popped kernels are larger and look more appetizing. The mushroom shaped popped kernels are used in popcorn balls or other sweets because its shape holds together better when mixed with a sauce. Keep an eye out for these different shapes. Popcorn is actually a distinct type of corn.
Count the number of popcorn kernels before and after popping. Record and compare these numbers. (Do not ask a child to count the kernels in a whole bag as the number will be overwhelming. Start with a handful of kernels. This will probably mean cooking the popcorn in oil on the stove as opposed to microwaving a bag. If cooking on the stove, an adult will need to supervise). How many of the pieces actually popped, or of those kernels counted, how many kernels did not pop?
Record the amount of time it takes for popcorn to pop. That is, if a bag goes in the microwave, how many seconds until the first audible pop? How many more seconds until there are no more audible pops? Popcorn pops because the natural moisture inside the kernel heats up turns to steam, and the resulting pressure explodes the kernel.
Count the number of rows on a corncob (sweet corn always has an even number).
Measure the size of a cob of corn. How long is it? What is its diameter (or length around)?
Measure the size of the kernels. Compare to a measurement of popcorn kernels. Which are larger, the fresh or the popcorn kernels?
If you buy a significant number of an unshucked ear of corn, see if you can find any worms. How many are there?
Take a poll. What are your family members’ and friends’ favorite foods made from corn? You may need to include a choice that allows people to say they do not like corn. Create a graph based on your findings.
Fun fact: Corn, or maize, provides about 21% of all the food across the world.
Sprout your own corn kernels. Place about ten kernels in a plastic bag on top of a wet paper towel. Seal the bag. Keep it out of direct sunlight. Wait for a couple of days. What happened? How many days did it take to sprout?
If your child has succeeded in sprouting corn seeds and carefully examined them, plant the seeds. You can plant them in a pot with soil, or to watch them grow, plant them in a plastic cup filled with wet paper towels. Place the sprouted seed between the damp paper towels and the side of the cup so that it can still be observed. Place the cup in a spot with sunlight, but not too much. Add drops of water as necessary to keep the paper towel damp. Check daily. Record any observations or draw images of how the plant is growing. Remember that when growing plants you can reinforce ideas about what plants need to grow, or air, water and nutrients. If growing the corn in paper towels, are there nutrients (no)? If not, where would nutrients come from (the soil)?
Elaborate and Glossary
Visit your library and find some books that focus on corn or the ancient people’s who grew it and depended on it for their survival.
Discuss the history of corn, although its origins are still somewhat of a mystery. Most historians/botanists think that corn started from a wild grass that was cultivated by people living in central Mexico. These early Olmec and Mayans cultivated and developed the crop. Over time, the ears grew larger kernels. Today’s modern corn, however, bears little similarity to the corn of 7000 years ago (some have suggested even 9000 years).
The thinking is that the corn developed by these people indigenous to Mexico worked its way into North America and south into South American where native peoples depended on maize, as corn is also known, as a major food crop. Corn husks were also used for a variety of purposes including shoes, clothing, baskets, and components of building a shelter.
The Western World’s introduction to corn came in 1492 after Columbus’ men discovered this new grain in Cuba. As Spaniards made their way up and down the coasts of South and North America they learned how important corn was to the diets of the indigenous peoples of the Americas. They then began to transport it back to Europe and from there it was introduced to other countries around the world.
Today corn is the most widely grown crop in the United States and we produce around 35% of the entire world’s annual corn crop. Much of it is processed into corn syrup or sweetener know as High-Fructose Corn Syrup (HFCS). Corn syrup contains the natural sugars fructose and glucose which are chemically the same as the common sucrose sugar produced from sugar cane or sugar beets. This HCFS is a common additive to an astonishingly wide variety processed foods. Because HCFS is liquid at room temperature it can help provide “moistness” in baked goods etc. It is also the ingredient that makes a lot of children’s oral cough and cold medicines palatable.