ANALYTICAL ASPECTS REGARDING THE FLAVOR COMPOUNDS IN BEER

Abstract

Contemporary population shows a great tendency to consume food capable of generating an intense feeling. Each food contains substances that generate sensations of taste and aroma. Beer is a food with specific flavor, which is mostly appreciated if, is fresh. It is considered that the beer flavor is dependent on the nature and the concentration of carbonyl compounds that are formed during the fermentation of the malt; the most important is the diacetyl (butandione). Carbonyl compounds in beer can be analyzed after a selective preconcentration. The methods of partial isolation as head space method and membrane process are designed to provide only qualitative information. For quantitative determination of carbonyl compounds present in beer, full extraction methods are used. The gas chromatographic separation method is used in order to study the mixtures obtained after the isolation of carbonyl compounds in beer. When the electron capture detector is used, only vicinal diketones can be identified and dosed in beer. The mixtures of 2,4-dinitrophenylhidrazone precipitates can be analyzed by spectrophotometric study or by liquid chromatographic separation. The analytical focus is the identification and dosing of the butandione and pentandione that have a key role in generating the sensation of flavor of beer. Brewers need rapidly and accurate information on the concentration of diacetyl in beer. In order to help the process, a neural sensor was proposed. It is used to determine the intensity of flavor sensation and it should provide the possibility of differentiating the products that come from different beer suppliers.