Hach-Lange DR 5000 brewerie analysis, supplementary software LZV570 - Manual (Page 17)

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Working procedures
Note: Analysis of additional samples: Repeat working procedure from
point 3. In other words, each sample has to have its own specific blank
value solution.
2.3.1.1 Executing the test with the sipper module
Information about the installation, module configurations and
sample introduction of the sipper module can be found in the user
manual of the DR 5000 Spectrophotometer (15.3.3. Installation
Sipper Module, page 133).
2.4 Anthocyanogens (Harris and Ricketts method)
Anthocyanogens (leucoanthocyanidins) are phenolic compounds,
which are transformed into red anthocyanidins by hot hydrochloric
acid. The amount and degree of condensation or polymerisation of
these compounds influence the formation of colloidal turbidities in
beer. Stabilisation measures with PVPP correlate with a reduction
in the anthocyanogen content.
Principle
The anthocyanogens are adsorbed on polyamide. The adsorbate is
dissolved in butanol and hydrochloric acid and heated. A red
solution is formed, whose intensity is measured with a photometer.
Fields of application
Beer, worts
Measuring range
0–100 mg/l
Accessories
• Shaker
• Centrifuge
• Mixing cylinder with ground-glass stopper (50 ml)
• Frit (1 G4)
• Suction flask
• Test tubes with ground-glass stoppers (30 ml, graduations to
25 ml)
• Vacuum pump
• Spectrophotometer (550 nm)
• 10 mm rectangular cuvette (OS grade)