As is the case with drinking water, water employed for the production of beer and soft drinks must be neutral in odor and taste.
beer, beer-based beverages, non-alcoholic beverages, mineral water
A qualitative test is performed after shaking the water in a sealed, odor-neutral bottle. Water possessing an odor is measured quantitatively on the basis of a sensory threshold. Water possessing an odor is diluted with odorless water until the odor is barely perceptible (by at least three people). The ratio of the total volume (water with odor + odorless water) to the volume of the mixture containing the water sample is designated as the odor threshold. The taste test should always be performed after evaluating the odor, since the perception of odor can be influenced by flavor.
This method describes how to determine the capacity for water imbibition (moisture uptake) in barley.
Barley intended for the production of malt is evaluated on the basis of its capacity for water imbibition.
Barley is steeped according to a defined scheme, and the absorption of the steeping liquor by the kernels at defined times is determined by calculating the moisture content. The moisture content after 72 h steeping time is used to assess the absorption of steeping liquor or the capacity for water imbibition in barley.
Whole hops intended for use in beer brewing or elsewhere in the food industry
Evaluation of the appearance of hop cones is performed through visual inspection and sensory assessment.
The method describes the conditions under which sensory analysis is to be conducted.
beer, beer-based beverages, non-alcoholic beverages, mineral water
One of the basic prerequisites for properly conducting sensory analysis is training the members of the tasting panel.
Determination of formic acid by enzymatic means.
This analysis is suitable for wort, beer, malt-based drinks, nutritional beer, beer-based mixed drinks, non-alcoholic soft drinks, NAB, fruit juice, soft drinks, juices, drinks.
Formic acid can be found in beer in small quantities, and it is also formed by contaminating bacteria, for example, by lactic acid bacteria (rods).
In the presence of the enzyme formate dehydrogenase (FDH), the formic acid created in this reaction is quantitatively oxidized to bicarbonate by nicotinamide adenine dinucleotide (NAD):
\(\text{Formic acide (HCOO}^- \text{) + NAD}^+ \space\text{+ H}{_2}\text{O }\space ^{\underrightarrow{\text{FDH}}} \space \text{CO}{_2}\text{ + NADH + H}^+\)
The amount of NADH+H+ formed during the reaction is equivalent to the amount of formic acid and can be determined photometrically based on its absorbance at 340 nm.
Whole hops intended for use in beer brewing or elsewhere in the food industry
Evaluation of the appearance of hop cones is performed through visual and manual inspection.