Highlight on chemcial compound research to determine factors affecting product quality of smell in insipid beer. A variant of the Maillard reaction (amino acids reacting with sugars) known from bread products while baking are identified to act in opened beer at room temperature. Reaction products (reactive dicarbonyles) change over time and reaction can be terminated using Aminoguanidine, which might as well serve as a conservation compund in beers to save flavor. Using neutralizers (1,2-DAB) at certain steps intermediate products can be conserved and isolated by gas chromatographcy and evaluated by olfaction afterwards. Above all the occurence of funraneol (caramel-like smell) and phenylacetaldehyde (rose-like smell) are identified to contribute to the "aged" smell of (in German): "lackes Bier".