Identifizierung von Aromastoffen aus der Kruste von Roggenbrot

The crust of freshly baked rye bread was extracted with methylene chloride. The volatile components in the extract, which showed a strong "crusty-caramel-like" odour, were isolated by vacuum sublimation and fractionated by column and high pressure liquid chromatography. By using simultaneous gc-analysis/sensory evaluation of each fraction components showing a distinct odour could be analysed by mass spectrometry and identified by comparison with authentic compounds. Among the 39 flavour compounds identified 2-acetyl pyrazine, 2-methyl-3-ethylpyrazine, 6,7-dihydro-5-methyl-(5H)-cyclopentapyrazine, 2-acetyl-1,4,5,6-tetrahydropyridine and 2-acetylpyridine were responsible for the crusty aroma notes and 2-methyl-3-hydroxy-pyran-4-one (maltol) and 2-acetyl-3-hydroxyfuran (isomaltol) for the caramel odours.