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Using a buffer solution, malt extract is produced, and then under defined conditions the extract is incubated on a specific substrate of BPNPG7 oligosaccharide (a p-nitropheny-maltoheptaoside blocked at the non-reducing end) in the presence of thermostable α-glucosidase. The α-glucosidase is initially unable to degrade the "blocked" oligosaccharide. Only when the oligosaccharide is hydrolyzed by the activity of the α-amylase (an endoenzyme) from the malt are the resulting fragments vulnerable to the enzyme. Then, they are quantitatively degraded to glucose and free p-nitrophenol by the α-glucosidase, which is present in excess.

Adding a weakly alkaline solution halts the enzymatic activity and simultaneously induces a color reaction. The absorbance measured at 400 nm is proportional to the activity of α-amylase in the sample.

Using a buffer solution, malt extract is produced, and then under defined conditions the extract is incubated on an azo-barley glucan substrate. The substrate is coupled with an azo dye, which is degraded by the β-glucanase activity to form low-molecular weight fragments. After addition of the precipitating agent, these fragments stay in solution and can be spectrophotometrically determined in the supernatant after centrifugation. The absorbance in the supernatant depends directly upon the activity of the β-glucanase in the analyzed malt.

Detection of harmful osmophilic and osmotolerant yeasts, moulds and bacteria using the pour-plate method.

Detection of aerobic mesophilic and thermophilic bacteria using the pour-plate method.

After boiling for two hours on a reflux condenser, the wort is clarified using membrane filtration. The color is measured with a spectrophotometer.