DIN Standards Committee Laboratory Devices and Installations
DIN ISO 20481
Coffee and coffee products - Determination of the caffeine content using high performance liquid chromatography (HPLC) - Reference method (ISO 20481:2008)
Kaffee und Kaffee-Erzeugnisse - Bestimmung des Coffeingehaltes mit Hochleistungs-Flüssigchromatographie (HPLC) - Referenzverfahren (ISO 20481:2008)
Overview
The International Standard ISO 20481:2008 has been adopted without modifications into a national standard. ISO 20481:2008 has been prepared by Technical Committee ISO/TC 34 "Food products" (secretariat: France), Subcommittee 15 "Coffee" (secretariat: Brazil) under German chairmanship and management of the interlaboratory test. The results of the interlaboratory test lead to the International Standard ISO 20481 with extended scope, which shall be adopted as DIN ISO 20481 into the national body of standards in order to replace DIN 10777-2:2000. This International Standard specifies a high performance liquid chromatography (HPLC) method for the determination of the caffeine content of: green coffee; roasted coffee; soluble coffee, regular and decaffeinated; and mixed instant coffee products (for example, soluble coffee/chicory mixes or soluble coffee drinks [mixed coffee beverage powders], cappuccino-type). Caffeine is extracted from samples with water of at least 90 °C in the presence of magnesium oxide. After filtration of the extract, the caffeine content is determined by HPLC on a RP-18 column using isocratic elution with UV detection at approximately 272 nm. If appropriate, the caffeine content may also be given on dry basis which requires a moisture determination by a suitable standard method. The collaboration of DIN for the field of responsibility of ISO/TC 34/SC 15 is performed through Working Committee "Coffee" of the Food and Agricultural Products Standards Committee (NAL).