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Titratable acidity represents the sum of the free acids present in a beverage, with the exception of the dissolved carbon dioxide (carbonic acid). In fruit juices and the beverages prepared from them, they usually consist of malic acid, citric acid and tartaric acid.

The titration of the degassed beverage sample (freed from carbonic acid) is carried out potentiometrically using 0.25 mol/l sodium hydroxide solution either to a pH of 7.0 calculated as tartaric acid or to a pH of 8.1 calculated as citric acid.

5-Hydroxymethylfurfural (HMF) is separated using HPLC and reversed phases. This substance is measured with a UV detector.
HPLC analysis specifically detects 5-hydroxymethylfurfural.

A photometric method, B-590.59.111 Hydroxymethylfurfural - photometrisch, using barbituric acid and o-toluidine detects all aldehydes present in the sample. This method serves as an alternative for laboratories without HPLC.

Volatile acids are distilled using steam, and the distillate is analyzed through titration. Sulfurous acid present in the distillate is determined iodometrically and subtracted from the total.

Capillary viscometers measure the kinematic viscosity of Newtonian fluids, unlike falling ball and the rotational viscometers, which directly measure the dynamic viscosity. However, with values for the kinematic viscosity and the density of the test liquid, the dynamic viscosity can be calculated.

The time required for a volumetrically defined amount of fluid (the volume between two marks on the tube of the viscometer) to flow through a capillary of a defined length is measured.

1 square meter per second of a homogenous fluid with a dynamic viscosity of 1 Pa × s and a density 1 kg/m³

The unit for expressing kinematic viscosity (the relationship of viscosity to density = viscoplasticity) is 1 m²/s = 10⁶ mm²/s

The kinematic viscosity is expressed as 1 square meter per second of a homogenous fluid with a dynamic viscosity of 1 Pa × s and a density 1 kg/m³.

5-Hydroxymethylfurfural (HMF) is detected in a color reaction with barbituric acid and o-toluidine. However, this detects all of the aldehydes present in the sample. The determination by HPLC specifically detects the HMF. As with other aldehydes, HMF reacts with barbituric acid and p-toluidine to create a reddish compound. HMF reacts with any sulfurous acid that is present, as do other aldehydes; in this case, it is, therefore, undetectable without prior treatment. If more than 10 mg/l of free sulfurous acid are present, this will bind to acetaldehyde. Subsequently, the determination can be performed. The presence of excess acetaldehyde does not interfere with the analysis.

α-Tocopherol and α-tocopherol acetate are separated using HPLC in reversed phases and determined with a fluorescence detector or a UV detector.