Fermentation has been used for thousands of years for raising bread, fermenting wine and brewing beer etc. The products of the fermentation of sugar by baker's yeast Saccharomyces cerevisiae are ethyl alcohol and carbon dioxide. Carbon dioxide causes bread to rise and gives effervescent drinks their bubbles. This action of yeast on sugar is used to carbonate beverages, which what you see in your soda and champagne thats all of the bubbles.
To preform this experiment you must set up a fermentation in a closed system and capture the generated carbon dioxide to carbonate root beer. You may of course adjust the quantities of sugar . The equipment you shall use is a clean 2 liter plastic soft drink bottle with cap, 1 cup measuring cup, a funnel, 1/4 tsp measuring spoon and1 Tbl measuring spoon1) Assemble the necessary equipment and supplies
2) With a dry funnel, add in sequence:
one level cup of table sugar (cane sugar)
3) Add: 1/4 teaspoon powdered baker's yeast ( fresh and active)
(Fleischmann's or other brand)
4) You can see the yeast granules on top of the sugar.
5) Shake to distribute the yeast grains into the sugar.
6) Swirl the sugar/yeast mixture in the bottom to make it concave (to catch the extract).
7) Add with funnel:
1 Tbl of root beer extract (I prefer Zatarain's, but Hires, etc. will work.)
on top of the dry sugar
8) The extract sticks to the sugar which will help dissolve the extract in the next steps.
9) Half fill the bottle with fresh cool tap water (the less chlorine, the better).
Rinse in the extract which sticks to the tablespoon and funnel. Swirl to dissolve the ingredients.
10) Q.s. [fill up] to the neck of the bottle with fresh cool tap water,