Don: (Mouth full, chewing something) Today on a Moment of Science--

Yael: Don, didn't anyone teach you not to talk with your mouth full?

D: Oh, sorry. (Swallows) I'm just doing some research for today's program.

Y: What do chocolate covered raisins have to do with science?

D: Well, Yael, haven't you ever wondered how candy companies get chocolate to      evenly coat things like raisins and milk balls?

Y: No, I guess I haven't. But I'm about to find out, huh?

D: Well, the centers of the candy are placed into what is called a coating pan, a machine      that resembles a cement mixer. The coating pan rotates like a dryer and sprays      melted chocolate over the candy centers that are tumbling around inside. It keeps      rotating until the chocolate cools down and solidifies. The idea behind the tumbling is      that every part of every piece of candy is exposed to the same amount of chocolate      spray. Then, during the cooling process, the tumbling prevents the candies from      sticking together, and smoothes any rough edges so that the candies come out round.      This process is repeated up to three times.

Y: But what about colored candies like M&Ms?

D: For sugar-coated candies, there are an additional two steps. After the chocolate has      solidified, the same process is used to spray colorful sugar liquid over the candies.      Finally, the candies get their gloss from a special type of vegetable oil that is solid at      room temperature. So you see, when I eat these raisins, (Starts chewing again) I'm      really just making sure the coating is even. Call it my own version of quality control.

Y: So, uh, Don, don't you need a second opinion on those raisins?  

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