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Little Miss Muffet
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Little Miss Muffet

Credit: Arlington Gregg
Source: http://commons.wikimedia.org/wiki/File:Little_Miss_Muffet_1940_poster.jpg
License: CC BY-NC 3.0

You?ve probably heard about ?Little Miss Muffet? and how she sat on a tuffet (whatever that is), eating her curds and whey. Did you ever wonder what curds and whey are? Read on to find out.

The Back Story

  • Curds and whey are two substances involved in cheese making. Both are products that form from milk. Making cheese goes back thousands of years. Although basic cheese making is a relatively simple process, it was probably first discovered by accident. People used to make cheese to preserve milk.
  • We no longer need to make cheese to keep milk from spoiling. We have other technology for that.
  • But people keep making and eating cheese because they love it. The average American, for example, eats as much as 35 pounds of cheese a year. People in some other countries may eat twice that much!
  • Credit: Tama Leaver
    Source: https://www.flickr.com/photos/tamaleaver/6222501420
    License: CC BY-NC 3.0

    With special ingredients added, this tub of milk will become cheese [Figure2]

     

  • So how do you get solid cheese from liquid milk? If you guessed that chemistry was involved, you?re right.
  • Watch this video to learn about curds and whey and the role they play in cheese making: http://www.nbclearn.com/chemistrynow/cuecard/51991 


Can You Apply It?

With the link below, learn more about the science of cheese and cheese making. Then answer the following questions.

  1. What is cheese?
  2. What type of change occurs to turn liquid milk into solid cheese, a physical change or a chemical change? How do you know?
  3. The first step in making cheese is denaturing the proteins in milk. What does this involve, and why is it done?
  4. What are curds and whey?
  5. List three ways proteins can be denatured. Which method is used in cheese making? 
  6. What is rennet? What does it do inside an organism? 
  7. Describe the roles of bacteria and rennet in cheese making.
  8. Cheddar, Swiss, mozzarella, blue...there are hundreds of different types of cheese. Even the same type of cheese may taste different if it is made from different milk. What are some of the many factors that influence the taste and texture of cheese?
  9. How was cheese making probably discovered?

Image Attributions

  1. [1]^ Credit: Arlington Gregg; Source: http://commons.wikimedia.org/wiki/File:Little_Miss_Muffet_1940_poster.jpg; License: CC BY-NC 3.0
  2. [2]^ Credit: Tama Leaver; Source: https://www.flickr.com/photos/tamaleaver/6222501420; License: CC BY-NC 3.0

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