Kvasny Prum. 1981; 27(8): 169-175 | DOI: 10.18832/kp1981030

The influence of surrogation on the formation of aromatic substances in beer.Peer-reviewed article

B. PARDONOVÁ, M. KAHLER

The surrogation by barley grist and liquid sugar caused a partial raising of the concentration of some fatty acids and a distinct elevation of the carbonyl substances. These quantitative changes have an undesirable influence on the quality of the final beer. The quick deterioration of the taste of botteled beer may be caused by oxidazing changes catalysed by an increased amount of iron in beer. The intensity of the oxidation depends, except the amount of air in beer, on the height of surrogation by liquid sugar. The high content of diacetyl, which was estimated in the beers surrogated by the barley grist only, makes immediately worse the quality of beers, namely during a relatively short time after the bottling. The vicinal diketons rise by the spontaneous decomposition of 2-acetolactate and 2-acetohydroxybutyrate, which are synthetized during the metabolism of valin and isoleucin. The concentration of these precursors drops mostly during the secondary fermentation at such a value, which, with regard to the rise of diacetyl after the bottling at beer, does not threaten its taste at all. In the case of higher surrogation by barley grist occurs probably accumulation of 2-acetolactate which, at the low temperature during secondary fermentation, is not completely decomposed and passes into the beer. Its presence is sensorically unpossible to identity, but the stability of taste is threatened just by its supplementary decomposition after the battling. According to the results, the height of the substitution by only barley grist is limited and should not overstep 10 - 12 % (dependence on the quality of the malt applied), in order that the organoleptic properties of the beer would not become distinctly worse. In our opinion is resp. balances the admissible height of surrogation by liquid sugar in the same extent as in the case of barley grist. An important index of this surrogate is the content of iron. In the case of surrogation by barley grist and liquid sugar in the proportion 1:1, the total dosis round 14 % is yet acceptable.
(In Czech, English summary only)

Keywords: surrogation, aromatic substances, beer

Published: August 1, 1981