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Evaluation of the appearance of hop cones is performed through visual inspection and sensory assessment.

After the initial testing of the raw materials ((refer to the list of relevant analyses under Links), the next significant critical control point is the quality of the wort. In monitoring the status of the sensory characteristics of wort it is essential that it is true to style (classification as wort for further processing to conform to defined beer style) and that it is free of any atypical sensory characteristics.

The source of these atypical characteristics can be grouped into the following:

environmental contaminants (e.g., metal ions, fecal indicator microorganisms, solvents, ...)

microorganisms (contamination)

differences due to chemical changes (oxidation, enzymatic reactions, thermal stress, incomplete reactions due to disruptions during processing, …) 

Due to its sustained influence throughout the entire production process, evaluation of the sensory characteristics of lactic acid from natural fermentation plays a decisive role in the final product. Large fluctuations in the quality of lactic acid cause significant differences in the resultant products.

The following influences should be tested within the scope of sensory analysis:

variations due to cross contamination

microorganisms (contamination)

variations due to microbiological or chemical changes (mutation, large percentage of dead microorganisms, …) 

In monitoring the status of the sensory characteristics of an intermediate product prior to testing the final product, it is essential that it is true to style (classification as a defined beer style) and that it is free of any atypical sensory characteristics. 

The source of these atypical characteristics can be grouped into the following:

environmental contaminants (e.g., cleaning and disinfection residues, metal ions, ...)

microorganisms (contamination)

differences due to biological and chemical changes (fermentation problems, oxidation, enzymatic reactions, thermal stress, incomplete reactions due to disruptions during processing, …)

As with the DLG score sheet, the individual criteria are assessed on a five-point scale. The criteria judged in the evaluation represent a combination of factors pertaining to the assessment of quality (purity of aroma, purity of flavor, quality of bitterness, overall quality) and intensity (bitterness, hop aroma, fullness, liveliness). It is important to note that with reference to fullness, an optimum score is 3 or 4.

Kaltner (2000) developed a score sheet for assessing beers with a strong hop flavor, which on one hand is based on the DLG quality assessment of beer (refer to S.590.53.700 Einzelprobenprüfung zur Qualitätskontrolle von Bier - DLG-Prüfschema für Bier). The criteria aroma, flavor, fullness, liveliness and bitterness are evaluated using a five-point scale in half-point steps, where 5 denotes a pure attribute and 1 indicates major faults. On the other hand, the quality and distinction of the hop aroma and bitterness are assessed. The aroma and flavor of the hop impression are also distinguished. The evaluation is also based on a five-point scale with an intensity of 5 corresponding to the attribute “perfume-like” and 1 to “not perceptible”. Under “quality of the hop aroma” a score of 5 is considered “pleasant” and 1 “unpleasant”. Additionally, the score sheet provides space for describing the sensory impression of the appeal of a particular hop note. The intensity of the bitterness is also evaluated on a five-point scale, and in this case, 5 denotes a very strong impression, and 1 a very weak one.

The appeal of the bitterness has been plotted on a graph and is expressed using the following terms:

• rapidly diminishing (low intensity)

• fine, harmonious (moderate intensity and pleasantly lingering)

• hard (high intensity and fleeting)

• lingering (high intensity and persistently lingering)