A practical method has been studied for the determination of caffeine in foods. A non-aqueous electrochemical technique was introduced for this purpose. Use of chloroform, acetic anhydride and benzene in 1 : 2 : 4 vol. proportions gave the most precise potentiometric curve with perchloric acid/glacial acetic acid titrant. Use of chloroform, acetic anhydride in 23 : 5 or 3 : 1 vol. proportions gave well defined conductometric curve. The lower limit of caffeine determiantion was about 0. 2 mg. Conductometric titration curves suggested that the conductance of the solution in the presence of a certain excess of titrant would have high correlation with caffeine content.
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