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Aside from evaluating the criteria flavor, fullness, liveliness and bitterness, based on the DLG Quality Assessment for Beer (refer to S.590.53.700 Einzelprobenprüfung zur Qualitätskontrolle von Bier - DLG-Prüfschema für Bier), the additional gustatory impressions of the four prevailing Southern German wheat beer styles are examined more closely. Thus, the sensory intensity and quality of the estery, phenolic, yeasty and malty notes in these beers can be assessed. Estery beers exhibit an evident fruitiness, of which the banana-like aroma of isoamyl acetate is the most prevalent. Wheat beers of the phenolic variety impart a clove-like impression, primarily due to 4-vinyl guaiacol, which at higher concentrations can be perceived as medicinal. Yeasty beers can exhibit a wide range of flavor-active fermentation by-products; however, old yeast and sulfur notes tend to dominate. Except of course for malty notes, wheat beers of a more malty or neutral character do not usually possess a distinctive aroma. The criteria are evaluated on a five-point scale, with 5 considered to be “pure” and 1 as “exhibiting major faults”. Scores are also possible in half-point steps.

Bottom-fermenting brewery yeast cultures cannot grow at a temperature of 37 °C. The majority of wild yeast species and top-fermenting brewery yeast cultures can grow at this temperature.

If bottom-fermenting yeast culture is inoculated into a universal yeast medium (e.g. wort, YPG, YGC or YM) and this is incubated at 37 °C, wild yeasts and top-fermenting brewery yeast cultures can be detected if contamination is present.