How and why does bread rise?

There are four basic ingredients needed when baking bread: flour, water, salt, and yeast. The yeast is the ingredient responsible for making the bread rise during the baking process. Without yeast, bread would be stiff and flat.

What is yeast? Yeast is a live, single-celled fungus. This fungus consumes the sugars in the flour, and then releases carbon dioxide bubbles. The released carbon dioxide is what makes bread rise. When bread is baked, the heat puts yeast in a highly excited state, producing carbon dioxide very quickly. That is why bread rises even more when it’s in the oven.

Who invented the
chocolate chip cookie?

In 1930, Ruth Graves Wakefield was making chocolate cookies at the Toll House Inn in Whitman, Massachusetts. When Ruth ran out of regular baking chocolate, she broke a bar of
semi-sweet chocolate into small pieces and added them to the dough, thinking they would melt into the batter. When the cookies were baked, however, the chocolate hadn’t melted. Instead, there were little chips of chocolate throughout the cookie. Ruth just invented the chocolate chip cookie. She eventually sold the recipe to Nestle.

What makes popcorn pop?

Popcorn, also known as popping corn, is a special kind of corn that expands from the kernel and puffs up when heated. Popcorn kernels contain oil and water with starch, and are surrounded by a hard and strong outer coating called a hull.

As the popcorn heats up, the water inside the kernel changes to steam and places great pressure on the hull, but the steam is unable to escape through the hull at this point. The hot oil and steam breaks down the starch inside the popcorn kernel, making it softer and more pliable.

The pressure continues to build, until the kernel finally explodes, breaking apart the hull and allowing the steam to escape. The inner starchy part bursts out at about forty times its original size and becomes the fluffy, airy popcorn we like to eat.


This month’s question was submitted by Marlene of Long Branch, NJ.

Dear Professor, what is the difference between white chocolate and dark chocolate?

Dark chocolate contains a lot of cocoa but very little milk (or no milk at all). While white chocolate isn’t really chocolate at all! It contains cocoa butter, but no cocoa.