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A Feast at Plimoth

Feast or Famine

Truth or Consequences


Mushroom Mania

The Bite Stuff
in the classroom


A dog's teeth are specially adapted to survival in the wild. But since most canine pets eat commercial dog food rather than game, dog teeth suffer from some of the same dental problems as people -- including plaque buildup. So one dog food manufacturer is working on another way to battle pet plaque: a dog food that acts as an edible toothbrush. Frontiers follows researchers designing dog food that will combat canine plaque and dental disease, as well as improve doggie breath.

Curriculum Links
Activity: Design a Snack
Consider This!



bacterial formation,
digestion, nutrition

chemical changes

dental hygiene,
nutrition, pet care


animal life,
digestion, nutrition

mass and weight

energy transformations

animal behavior,
market analysis,
persuasive techniques


As you've learned on Frontiers, no matter how nutritious and beneficial a food may be for people or pets, the product must be visually appealing. Market researchers test various food appearances to test the appeal of new products. Obviously, texture and taste are also important factors in the creation of a successful product. Sometimes, all it takes to achieve a major marketing success is a small change in appearance.

You are going to become a food designer by developing a custom snack mixture. Your creation will be tested by your classmates and a winning snack mixture selected. Before beginning this activity, review the techniques for preparing and handling food. If you are working in groups, meet with your group members to brainstorm your design before making any purchases.

  • various snack products: pretzels, chips, cereals, nuts, dried fruit, candies, raisins, etc.
  • balance for determining mass
  • bowls, scoops or spoons

  1. Place each ingredient in its own container.

  2. Create a custom snack mixture by combining a variety of ingredients in a large bowl. Use clean scoops or spoons to blend the ingredients. Make the final blend visually appealing.

  3. Record each ingredient and its mass in grams on a data chart as you add it to the mix. See if you can create a mix that totals 100g. (Calorie information is on the nutrition label.)

  4. Create an ad campaign for your snack. Remember to advertise such features as low-fat or low-salt content (but be ready to support your claim). Prepare a short video or print advertisement for your class or taste-testers.

  5. Display your completed snack blend on a judging table. Vote on the blend you like the most. When the voting is over, identify the food designer(s) of each mixture.


  • Can you think of any foods that might work as "edible toothbrushes" for people?

  • How does bacteria in the mouth cause plaque buildup and bad breath?

  • Compare labels on pet foods to learn the nutritional needs of different animals.

  • Many vegetarians believe their pets should be vegetarians as well. Discuss the pros and cons of this approach.

  • Conduct a consumer survey to find out why people buy certain pet foods.

NOTE TO THE TEACHER: You may wish to work with a home economics instructor on the snack project. This project can be completed by individuals or in cooperative groups. Students who are allergic to peanuts or other foods may wish to refrain from handling the food, and can work on the math or advertising aspects of the project.

  • Pets are big business. Americans spend $15 billion on pet food and supplies each year. How much of this expense is necessary? For example, do dogs and cats need sparkling water? Do hamsters need dessert? What factors influence people's buying decisions?


Scientific American Frontiers
Fall 1990 to Spring 2000
Sponsored by GTE Corporation,
now a part of Verizon Communications Inc.