Root Beer Lab
Root beer was made by our forefathers by soaking Sassafras (a type of tree) root in water, and adding sugar and yeast (yeast for carbonation). In the early 1900's however, scientists discovered that safrole, a chemical found in Sassafras root, was a carcinogen (which means it is a cancer causing agent). Now, a mixture of other herbs and spices makes up "root beer extract" which is what we now use to make homemade root beer.
Respiration is the breakdown of sugar (glucose) to form ATP (a form of energy for an organism). There are two types, aerobic and anaerobic (also called fermentation). Yeast cells (a type of fungus) obtain energy from glucose (sugar) by a specific anaerobic process called fermentation. There are two types of fermentation, lactic acid fermentation (which occurs in muscle cells when they are oxygen deprived), and alcoholic fermentation, which is involved in the making of food products. Alcoholic fermentation begins after glucose diffuses into the yeast cell. The glucose is broken down into two, three carbon molecules called pyruvic acid. The pyruvic acid is then converted to CO2, ethanol, and energy for the yeast cell. Fermentation is used to make a variety of food products, including the making of beer, wine, bread, cheese, sauerkraut, and baked goods. It is the carbon dioxide produced by the yeasts that give root beer its "fizz." This fizz is produced in store bought root beer by a carbonation machine that forces carbon dioxide into the root beer mixture, without the aid of our little yeast friends.
Equation for respiration:
C6H12O6 + O2 ---> CO2 + H2O + ATP
Clean empty 2 liter plastic bottles + caps; Large Bowl; Funnel; Mixing spoon; Water (preferably spring water); Brewer's yeast (the dry kind), Rootbeer extract; Sugar; Measuring spoons; and cups.