Ever notice how cookies lose their crispness when they've been exposed to air for a while? Cookie manufacturers have. That's why they seal their products in packages that keep them from being exposed to water vapor in the air. The ingredient in cookies that is chiefly responsible for absorbing moisture is sugar. Such a substance is described as hygroscopic, which means "wet looking."

Is one kind of sugar more hygroscopic than another? This experiment compares cookies made with granulated sucrose and those made with honey. Taste honey and sugar. Which is sweeter?

Materials & Equipment   

• 2 cups flour
• 1 teaspoon baking powder
• 1/2 teaspoon salt
• 1 stick (1/2 cup) unsalted butter
• 1/2 cup sugar
• 1 egg
• 2 tablespoons water
• 1/2 teaspoon lemon juice
• 1/4 cup honey
• measuring cups and spoons
• a flour sifter
• a fork
• 4 bowls
• electric mixer or eggbeater
• waxed paper
• greased cookie sheets
• a metal spatula
• wire cooling racks

Procedure

1. Preheat the oven to 400°F. Sift 2 cups of flour onto waxed paper. Measure out 1 cup of this sifter flour and resift it together with 1/2 teaspoon baking powder and 1/4 teaspoon salt into a bowl.
   

   Resift a second cup of flour with 1/2 teaspoon baking powder and 1/4 teaspoon salt into a second bowl. Set dry ingredients aside.

2. Put 1/2 stick of softened butter into a third bowl. Beat until creamy with an electric mixer or eggbeater. Add 1/2 cup of sugar to the butter and continue beating until thoroughly mixed.

   Beat the egg with a fork in a measuring cup. Put half the egg into the butter-sugar mixture. Also add 1 of the bowls of dry ingredients, water, and lemon juice. Blend until smooth.

3. Now prepare the batter with honey. Put the remaining 1/2 stick of softened butter in a fourth bowl and beat until creamy. Beat in the honey. Add the other half of the egg and the second bowl of dry ingredients to the butter-honey mixture. You do not need to put in lemon juice, as honey already contains an acid. Mix until well blended.

   Drop small spoonfuls of batter onto greased cookie sheets, leaving about 2 inches between cookies. Bake until brown around the edges, about 7 minutes. Be sure to keep track of which cookies contain sugar and which contain honey.

4. Let the cookies cool for few minutes on the sheets before moving them to a wire rack with a metal spatula. When they are completely cool, store the cookies in airtight containers.

Observations

When they are cool, eat a sugar cookie and a honey cookie. Are they about the same crispness? Are they the same color? Which is browner? Leave one of each kind of cookie exposed to the air. Take a bite of each every few hours. Which cookie loses its crispness more quickly? If you wanted to make a cake that would stay moist for a long time, what might you use to keep it moist?