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Kernels with a visually recognizable fungal infection is distinguished primarily by a black but at times pinkish red (barley) or white (wheat) discoloration over part or all of its surface. Pinkish red or white kernels indicate an infection by a species of Fusarium.

Fusarium graminearum contamination in barley or wheat can be visually determined with the naked eye after three to five days of incubation on mannitol agar.

Fusarium culmorum contamination in barley or wheat can be visually determined with the naked eye after three to five days of incubation on mannitol agar to which malachite green has been added.

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.

The time required to develop a product – from conception to launch on the market – is steadily shrinking. Since recipes are also becoming ever more complex and a wide range of different types of packaging are now employed, forced stability tests have become absolutely essential, in order to establish a realistic indication of a product’s shelf-life.

Inferences about the shelf-life of a product can only be made if the entire beverage concept is taken into consideration, such as the recipe, filling technology, packaging and distribution.

The most important stress factors in the aging process are heat, light and oxygen.

PET bottles have become a popular form of packaging for non-alcoholic beverages, and their permeability to gas, most especially oxygen, is therefore a critical parameter in the aging process.

The testing process described below operates, of course, on the assumption that the chemical reactions in the aging process are subject to the same mechanisms, whether they occur at temperatures typical for beverage storage or at somewhat elevated temperatures, and that they follow a linear relationship dependent on temperature. The same applies to forced photochemical reactions and to reactions brought about by an increase in the partial pressure of oxygen on the beverage. To verify results from forced testing, they can be compared and correlated to results from real-time tests on the same product.