Isolating and Comparing Caffeine Concentration in Differing Types of Tea

The objective of this experiment was to determine which type of tea – black, green or white – contained the highest concentration of caffeine, (C8H10N4O2). A common myth states that the darker the tea, the higher the concentration of caffeine is present. Effectively, this experiment tests this myth. Caffeine was isolated from the different types of tea with the use of a centrifuge, which separated the organic and inorganic layers. Dichloromethane, (CH2Cl2) was used to aid in the separation of the layers, and sodium sulfate, (Na2SO4) separated the water from the caffeine. The mass of the caffeine was found after evaporating the dichloromethane and sodium sulfate overnight in a fume hood. The recorded mass of the caffeine and the known volume of the tea were used to calculate the concentration of caffeine in the tea for each trial. An ANOVA test was executed to analyze the results. Our ANOVA test results caused us to reject our initial hypothesis, which stated that black tea had the highest concentration of caffeine and the white tea had the lowest concentration of caffeine. However, our results were so close to the accepted value that they cannot give a definite result. This experiment tested the myth that the darker the tea, the higher the concentration the caffeine. This study was important because many people turn to tea as a source of caffeine. By knowing the amount of caffeine they ingest, they can monitor their intake of caffeine and limit their use.

Research Done By:

Stephanie Bamford
Lake Shore

Lindsay Stoyka