The determination of caffeine

✍ Scribed by F. J. T. Harris

• Publisher: John Wiley and Sons
• Year: 1953
• Tongue: English
• Weight: 328 KB
• Volume: 4
• Category: Article
• ISSN: 0022-5142
• DOI: 10.1002/jsfa.2740040409

✦ Synopsis

Abstract

Very many modifications of the basic method for the determination of caffeine in coffee products have been proposed from time to time. In a search for a rapid and reliable method all the steps and many alternative procedures have been considered. As a result, a method is now described which, although presenting few novel features, meets all the requirements and gives results of better‐than‐average accuracy. The accuracy of the method has been proved by checking actual manufactures.

Caffeine can be extracted from a solution‐buffered with trisodium phosphate, and determined by a Kjeldahl digestion. Zinc ferrocyanide is a satisfactory clarifying agent, provided that it is removed by filtration within, say, 15 minutes.

The accuracy of the proposed method is approximately 1% from the recovery experiments. A number of experimental batches of coffee and chicory essence were examined, and satisfactory agreement was found between calculated and determined caffeine contents.