A Determination of the Aspartame Content in Select Diet Beverages

Stephen F Austin State University, Baker Pattillo Student Center, Twilight and Grand Ballrooms

Millions of dollars are spent every year on diet beverages and there has been much controversy on the contents in these beverages, mainly the artificial sweetener aspartame. It is known that aspartame is included in many diet beverages, but the actual amount of aspartame used is not listed in the nutritional facts or provided by the beverage manufacturers. For this reason, the aspartame content of various soft drinks, Coke Zero, Pepsi Max, Diet Pepsi, and Pepsi Next, was analyzed and compared to a calibration plot utilizing Diet Coke as a standard. Diet Coke was used due to the unavailablity of an aspartame standard. This experiment was carried out using High Perfromance Liquid Chromatography to allow for the separation of aspartame from the other components in these beverages. Since a standard Diet Coke was used, aspartame was measured in Diet Coke Units (DCU). This was the devised unit used to allow for the aspartame content of the sample drinks to be compared to Diet Coke standards. This experiment showed that there was an aspartame concentration of .07853 DCU, 1.5779 DCU, 0.8140 DCU, and 0.9269 DCU for Coke Zero, Pepsi Max, Diet Pepsi, and Pepsi Next respectively.