COMPOUNDS CONTRIBUTING TO THE CHARACTERISTIC AROMA OF MALTED BARLEY

The volatiles from malt, sampled at stages during roasting, were exami ned by GC odor-port evaluation and by GC-MS. The technique of odor dil ution was applied to volatile extracts from samples exhibiting strong malt-like characteristics. Seven odors from the GC column persisted th rough several dilutions. 3- and 2-methylbutanal were responsible for t he odors with the highest dilution factors which had malty characteris tics. The other five odors were malty or cereal-like; ethylmethylpyraz ines and maltol may contribute to these odors, but other compounds res ponsible were present at very low concentrations and have not yet been identified. The levels of 2- and 3-methylbutanal increased dramatical ly in malt during roasting.