Sophia+and+Lexi

Abstract: **CARBONATION OF HOMEMADE GRAPE SODA VS. COMMERCIAL GRAPE SODA. Sophia Myers-Kelley & Lexi Taylor.**  In this lab two homemade sodas, one made with light corn syrup and the other made with white granulated sugar, were carbonated through fermentation with yeast and compared to commercial grape soda. A hydrometer was used to measure the alcohol content of the sodas and the PV=nRT equation was used to determine the pressure of the CO 2 of the homemade sodas and the commercial soda. In order to measure the pressure in the bottles with the homemade sodas, find the volume of the gas, the mass of the gas, and the temperature of the gas. Unfortunately, the homemade soda’s carbonation could not be measured due to mechanical failure, but the alcohol content of the corn syrups was higher than sugar, implying that fermentation and respiration occurred more quickly in the corn syrup soda than the sugar soda.

Keywords: Fermentation, hydrometer (Saccharometer), PV=nRT

Project Topic: The Comparison of the Carbonation of Homemade and Commercial Beverages.

Chemistry Concept: Fermentation of Sugars and Yeast Into Carbon Dioxide

Hypothesis: The corn syrup soda will have higher carbon dioxide levels than the sugar soda, but the commercial beverage would have the highest carbon dioxide level.

Journal Article: The Effect of Different Sugars on the Rate of Fermentation in Yeast, [|Brew Better at Home], [|Adventures in Homebrewing],[|Pressure in a Can of Soda], [|Introduction to Pop]

Lab Procedure:


 * Part One -**
 * Make the homemade grape soda with white sugar
 * Measure 1/8 cup of white sugar, 1/2 cup of water, and begin to heat, then add 1/2 cup of grape juice
 * Heat up the contents for 5 minutes, stir occasionally
 * Add the 1 gram or less of the yeast to the mixture and pour into the plastic bottle (Leave at least 1 inch of space at the top)
 * Mass the bottle. Record.
 * Store somewhere in room temperature for 24 hours
 * After letting it sit for 24 hours and let the bottle get firm, then refrigerate it.
 * Part Two -**
 * Make the homemade grape beverage with corn syrup (fructose)
 * Measure 1/8 cup of corn syrup, 1/2 cup of water, and begin to heat, then add 1/2 cup of grape juice
 * Heat up the contents for 5 minutes, stir occasionally
 * Add 1 gram or less of the yeast to the mixture and pour into the plastic bottle (Leave at least 1 inch of space at the top)
 * Mass the bottle. Record.
 * Store somewhere in room temperature for 24 hours
 * After letting it sit for 24 hours and let the bottle get firm, then refrigerate it.
 * Part Three -**
 * Open and mass the bottles. Record.
 * Measure the ethanol content with the hydrometer.
 * Measure the temperature, the mass, and the volume of the gas.

Materials Needed and Apparatus :
 * Baker's yeast
 * 1 Funnel
 * 2 Plastic containers to hold the beverages
 * Beaker
 * Grape juice
 * Commercial grape soda
 * Corn syrup
 * White granulated sugar
 * Water
 * Hot Plate

Safety Information Chemicals/Reaction: Flammable contents (alcohol resulting from yeast fermentation) should be handled with care. If you use too much yeast, then the pressure within the bottle after letting it ferment will be extremely high, so open the bottles under "the hood" to prevent the cap fro shooting off at people.

Notes:

To carbonate the soda, you need to add yeast. The yeast will eat the sugar in the soda and create CO2 to carbonate it. You want to do this in plastic bottles and NOT glass. Second, you need to be testing the bottles a few times a day to make sure you stop the yeast before it creates much alcohol. To do this with a plastic bottle is pretty easy, just squeeze the bottle a few times a day,

and as soon as it feels hard you're done. At this point just toss it in the fridge to force the yeast to go dormant, and you're good to go! media type="file" key="Carbonation of Homemade Soda versus Commericial Soda.wav" width="300" height="50"