Acids known to be decomposition products of carbohydrates were quantified in raw, dried and roasted chicory roots and in dried and roasted barley malt by means of gas liquid chromatography/mass spectrometry and isotachophoresis. Acids derived from other educts will be dealt with in following papers. Of the acids found, eight are of the aldonic type, ten are deoxyaldonic, three are oxo acids, two are derivatives of furanoic acid, two are volatile acids and the others are methyl succinic and oxalic acid. Qualitatively, chicory and malt are composed of the same acids, but generally speaking the concentration of acids in chicory is higher. While in the dried educts only trace amounts can be detected, the concentration of acids increases upon roasting. In roasted chicory roots considerably high contents of acetic, formic, glycolic, pyruvic, lactic, metasaccharinic, oxalic, glyceric and 3-hydroxypropionic acids were quantified. 5-Hydroxymethyl-2-furanoic, 2,4-dihydroxybutyric, 3,4-dihydroxybutyric, arabonic, gluconic, ribonic, erythronic, threonic, 4-oxovaleric, methyl succinic, 2-furanoic, mannonic, 3-deoxypentonic, saccharinic, isosaccbarinic, methyl glyceric and 2-oxovaleric acids are minor compounds. In malt samples only acetic, pyruvic, formic, oxalic and lactic acids were detected in relatively high concentrations. Gluconic, 3,4-dihydroxybutyric, 3-hydroxypropionic, metasaccharinic, mannonic, glyceric, glycolic, 2,4-dihydroxybutyric, ribonic, threonic, 5-hydroxymethyl-2-furanoic, erythronic, 4-oxovaleric, 2-furanoic, saccharinic, methyl succinic, arabonic, 3-deoxypentonic, methyl glyceric, 2-oxovaleric and isosaccharinic acids are minor compounds