When you drink soda, bubbles of carbon dioxide (CO2) cause the tingling sensation on your tongue. In addition to the physical sensation, the CO2 combines with your saliva to produce carbonic acid, which is an important flavor component of carbonated beverages. If you’ve ever taken a swig of flat soda or beer, you’ll know that the carbonation is really important.
For a healthy treat, you can add the sparkling qualities of CO2 to fresh fruit in your own kitchen. You can achieve this with solid CO2 (dry ice), but it has to be measured very carefully due to the pressurized nature of this project. Using effervescent tablets like Alka-Seltzer is a great alternative since they have a long shelf life and produce a known quantity of CO2.
Caution #1: This is a high-pressure project. Use plastic instead of glass, and keep the lid pointed away from yourself and others.
Caution #2: Aspirin is an ingredient in regular Alka-Seltzer. Make sure to buy the aspirin-free version.