Experiment 10B Caffeine in Soft Drinks
Caffeine was measured using 5 0 mL of concentrated cola drinks. The caffeine was extracted
using methylene chloride in a separatory funnel. Crude and pure caffeine amounts were
determined by checking melting point ranges.
Introduction & Bibliography
The melting point of caffeine is 237º C. The boiling point of methyl chloride is 40º C. The
methylene chloride is used to separate the inorganic products from t he organic products, then to
remove residual water by filtering and finally having the m ethylene chloride evaporated to have
the final product: crude caffeine. Some alternative techniques for extracting caffeine from food
products include supercritical ext raction ………
1) Take 50mL of Pepsi sample and add 10 -15 mL of ammonium hydroxide and extract with
methylene chloride and extract twice.
2) Weigh an empty beaker and place under a funnel. Fitrate through a methylene chloride paper
barrier to remove any residual water from the caffeine extraction
3) In a fume hood place the beaker with the extract onto hot plate and heat to 40º C. After heating
and removing the methylene chloride the crude caffeine will be leftover. Then cool to room
temperature and weigh the beaker.
4) Scrape the crude caffeine from the be aker into a watchglass and take a capillary tube and dip
the open end into the crude caffeine and afterward invert the tube.
5) Take your capillary tube and place into a