Ask Dr. Universe: Why does soda fizz?

Dr-Universe-230PULLMAN, Wash. – If you’ve ever had flat soda, you know a sip isn’t the same without some fizzy bubbles. We can hear them pop and feel them burst on our tongue.

I wondered if there was some secret ingredient that made soda bubbly. My friend Kenny McMahon, who researches food science here at Washington State University, and I decided to investigate.

We grabbed a balloon, a bottle of soda and salt. We filled the balloon with about a teaspoon of salt. Then, we twisted the cap off the bottle and stretched the balloon over the top. When the balloon was secure, we tipped in the salt.

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