ICUMSA Method GS9-8 (2026)
Material: Plantation White Sugar, White Sugar, Raw Sugar
Analytes: Colour in solution
Method Technique: Spectrophotometry
Abstract:
The colour in solution of raw sugar, affined raw sugar, white sugar and plantation white sugar up to 16,000 ICUMSA Units (IU) is determined at pH 7.0. It must be ensured that a filtered solution can be prepared by the procedure specified in the method. The absorbance of a filtered solution at pH 7.0 is measured at 420 nm in a spectrophotometer, with MOPS buffer used to adjust the pH of the solution. This method has ICUMSA® Official (Reference) status. Its use is recommended in any case of dispute. However, for white sugar, Method GS2-10 gives equivalent results to this method up to 50 IU. Precision data in terms of Repeatability and Reproducibility for sugars with ICUMSA® Colour in the range of 10 to 16 000 ICUMSA Units (IU) at pH 7.0 are given in the table below.
| ICUMSA® Colour in IU | 95% Repeatability r (IU) | 95% Reproducibility R (IU) |
| Below 50 | 3 | 8 |
| 50 to 250 | 9 | 18 |
| 250 to 1000 | 23 | 68 |
| 1000 to 5000 | 48 | 140 |
| 5000 to 16 000 | 210 | 320 |
Online Access to ICUMSA Method GS9-8 (2026)
Access to the online Version of ICUMSA Method GS9-8 (2026) can be obtained from the Sugar Industry Website, operated by Bartens. The online access for two years costs EUR40 (+ 7 % VAT for German and EU citizens without EU VAT No.).