Rhodora Collins, DeKalb County Farm Bureau – Agricultural Literacy 2011 – rcollins@dekalbfarmbureau.org

Corn Uses Guessing Game

Objectives Students will:

1. Describe food and non-food uses of corn.

2. Identify different kinds of corn, and understand that field corn is the most commonly grown and used.

Overview

This guessing game encourages students to think about the origins and composition of many products that enhance our lives. Corn is an amazingly versatile and useful crop that touches our lives constantly. Rather than focus only on products that contain corn, however, the focus of this activity is uses for corn. This subtle difference helps make the point that corn isn’t just a ubiquitous food ingredient, but a renewable resource used for many non-food products. It also allows for discussion of a major use of this crop: livestock feed. (After all, corn doesn’t just show up in the products we use and eat. It also helps feed animals that in turn feed us.)

Having students guess how corn is used is an ideal jumping-off point to share interesting corn facts (who knew socks could be made from corn?) and dispel misconceptions, depending on the age and interest level of the group.

Materials

Corn kernel-shaped signs OR sheets of paper numbered 1-12 with the words “yes” and “no” next to each number (1 per student).

Sticky notes numbered 1-12 in large enough print for students to read from their seats.

12 food and non-food items that represent uses for corn. Possible products:

1. Corn Flakes cereal – contains corn meal, corn flour, and corn syrup

2. Soft drink (regular, not diet) – sweetened with high fructose corn syrup

3. Gel-style deodorant – made with ethyl alcohol (ethyl alcohol is another name for ethanol) *ingredients list may say “alcohol denat” short for denatured alcohol; typically the kind used is ethyl alcohol

4. Ketchup – sweetened with corn syrup 5. Toy car or truck – uses ethanol-blend fuel 6. Dairy cow (photo or toy figure) – consumes

feed which contains corn 7. Doritos, corn chips, or nacho chips – made

with whole ground corn 8. Biodegradable plastic cup or other

container – made from corn-based PLA 9. Socks or other clothing item – made from

Ingeo™ PLA corn fiber 10. Pig (photo or toy figure) – consumes feed

which contains corn

11. Hand sanitizer – 62% ethyl alcohol, which is ethanol

12. Pad of paper or book – corn starch is used in most paper as a binder and to improve printability

Additional product options: other breakfast cereals, deodorant containing corn starch, baby powder containing corn starch, etc.

“How We Use Corn” display showing sample of four common corn-based ingredients: corn flour, corn starch, corn syrup, and ethanol

Ears of field corn, popcorn, Indian corn, and photo of sweet corn (use an actual ear if available)

Optional: globe (or world map) – use to discuss the use of corn for export to other countries.

Procedure

Before class: Place the items in a row on a table in the front of the classroom. Place one numbered sticky note on the front edge of the table below each item.

When class begins, make sure you do NOT mention that all of the items are uses for corn!

1. Ask students: “Do you ever think about what things are made of? As you are eating your breakfast cereal in the morning, do you ever wonder what’s in it? Or, if you’re drawing a picture, do you ever wonder what’s in the paper you’re drawing on?”

2. Explain that you are going to challenge students to think about how corn may or may not be used for many everyday items. Pass out kernel-shaped signs or Yes/No worksheets.

3. Explain that you are going to hold up each item, one at a time. Students should raise their kernel sign if they think the item you are showing uses corn, and keep it down if they think it does not. (Alternatively, students may circle yes or no on their worksheets.)

4. Show each item in order by number and give students time to decide whether or not the item is a use for corn. Set each item down near its number.

5. After you have shown all of the items, invite the group to share how many they thought used corn.

Rhodora Collins, DeKalb County Farm Bureau – Agricultural Literacy 2011 – rcollins@dekalbfarmbureau.org

“How many of you think less than half of the items use corn? More than half? Most of them? Did anyone think corn was somehow used for all 12 items? If you did, you were right!”

6. Explain how each item is a use for corn (see explanations in materials list). Point out ingredient labels where appropriate, and give students a chance to read the ingredients out loud, especially for items like ketchup and hand sanitizer.

7. “Okay, so all of these items somehow use corn. What KIND of corn are we talking about?

a. Is it this kind of corn? (Hold up photo of sweet corn.) No. What kind of corn is this? This is sweet corn, which we eat as a vegetable. You can find it canned, frozen, or on the cob.

b. Is it this kind of corn? (Hold up ear of popcorn.) No. What kind of corn is this? This is popcorn. (Popcorn can be many colors, but the most common ones we eat have yellow or white kernels. All popcorn pops white; it’s just the outside of the kernel that is different.)

c. Is it this kind of corn? (Hold up ear of Indian corn.) No. What kind of corn is this? This is Indian corn. Some Native Americans may still grow and use this as a traditional food, but mostly it is just used as a fall decoration.

d. Is it THIS kind of corn that is used for all these items? (Hold up ear of field corn.) YES! What kind of corn is this? This is field corn. Ninety-nine percent of the corn grown in our country is field corn, because it can be grown in many climates and soils and used for so many different things.

8. Pass around the “How We Use Corn” display board so that students can view common corn ingredients.

Summarize: Corn is obviously not the only thing farmers grow or raise. But we have learned that there are many ways just this one crop is important in our lives. What other farm products do we benefit from every day?

Points of discussion (depending on age of group)

When corn is used to make ethanol, only the starch in each kernel becomes fuel. The remaining 30% of the kernel (protein, fat, minerals, and vitamins) is made into a high-quality livestock feed, in turn producing nutritious meat and milk for humans.

We produce enough corn that we can export 1 in every 5 rows of corn each year. Exports of corn and other ag products helps the U.S. balance of trade.

High-fructose corn syrup was formulated to be virtually identical to table sugar in composition and

taste, but in liquid form. The human body cannot tell the difference between the two. Unfortunately, high-fructose corn syrup has a misleading name. On the website www.bestfoodfacts.org, Arthur Frank of George Washington University explains:

“Table sugar, sucrose, is a chemical compound containing equal parts of two smaller sugar molecules, glucose and fructose. Until 1968 the sugar derived by deconstructing the complex corn starch molecule yielded glucose alone. Mechanisms were developed then to convert some of that glucose to fructose. Eventually, the chemists were able to increase the production of fructose so that the mixture contained equal amounts of glucose and fructose, comparable to table sugar. Pleased with their achievement of increasing the fructose content of corn syrup, the new product was given the unfortunate and misleading name ‘high fructose corn syrup’. Quite reasonably, HFCS is thought to contain high amounts of fructose, with all of the assumed consequences which derive from high amounts of fructose. Higher, yes, than corn syrup alone, but not higher in fructose than ordinary table sugar. HFCS is the equivalent of table sugar, nutritionally, chemically and functionally. It does not have significantly high fructose content if you compare it to sucrose which is what it replaces in so many of the foods we eat.”

Plastic food packaging and fiber for clothing or carpet can be made from corn starch. The starch is converted to sugar, from sugar to lactic acid, and from lactic acid to polylactide (PLA). PLA can be formed into compostable plastic or extruded into a renewable-source, synthetic (man-made) fiber.

Even though it is technically a grain, we treat sweet corn as a vegetable. We actually eat it when it is immature (at the “milk stage”). When we use food-grade field corn in foods such as cereal, tortillas, or breads, we are using it as a grain similar to the way we would use oats or wheat.

Extensions

Dissect softened corn kernels to identify the parts, and discuss how they are used in products. (See Corn Kernel Dissection lesson in Corn Literacy Kit.)

Explore how corn harvest has evolved over time. Conduct corn shelling contest. (See Corn Shelling contest activity in Corn Literacy Kit.)

Use seed corn to make germination necklaces. (See Germination Necklaces lesson in Corn Literacy Kit.)

Related resources

Corn Ag Mag – www.agintheclassroom.org

Corn Fact Book – www.cornfarmerscoalition.org

Corn plastic information - www.natureworksllc.com

Objective answers to questions about food – www.bestfoodfacts.org

Print kernel shapes on card stock, cut out and mount on paint stirrers to create kernel signs.