The β-glucan content of barley intended for use in beer production should be known.
Malt intended for use in beer brewing or elsewhere in the food industry
This method describes how to determine the β-glucan in laboratory wort by means of a fluorimetric method using microtiter plates (MTP).
Applicable for all (laboratory) worts
This method describes the general requirements for boiler feed water:
Boiler feed water for use in the production of beer and other foods
The requirements for boiler feed water are detailed in the analysis methods listed below.
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.