ISO 10504 pdf download Starch derivatives — Determination of the composition of glucose syrups, fructose syrups and hydrogenated glucose syrups — Method using high- performance liquid chromatography
This International Standard describes a high-performance liquid chromatographic (HPLC) methodfor measuring the composition of dextrose solutions, glucose syrups, fructose-containing syrupshydrogenated glucose syrups, sorbitol, mannitol and maltitol. The constituents are mainly glucosemaltose, maltotriose,fructose, sorbitol, mannitol, maltitol and malto-oligosaccharides.
The use of a column packed with cation-exchange resin is essential.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and areindispensable for its application. For dated references, only the edition cited applies. For undatedreferences, the latest edition of the referenced document (including any amendments) applies
ISO 3696:1987, Water for analytical laboratory use – Specification and test methodsISO 5381:1983,Starch hydrolysis products – Determination ofwatercontent- Modified Karl Fischermethod
Saccharide components are separated using high-performance liquid chromatography. Separation isachieved using a cation-exchange column with water as the eluent. The eluted components are detectedby means of a differential refractometer, and quantified using an electronic integrator.
All reagents used shall be of recognized analytical reagent grade.
4.1Special distilled water.
The water used may be double-distilled of quality grade 1 in accordance with ISO 3696. The mostsuitable is demineralized water, which prevents contamination of the ion-exchange resin.
The water should be filtered by passage through a 0,22 um filter. Also,it should be degassed by treatmentunder vacuum, or by use of an in-line degassing unit. The water should be maintained under an inertatmosphere, and preferably at 70 ·C to inhibit microbial growth.
NOTESome commercial water-purification devices produce water which is both filtered and degassed.
4.2Primary standard solutions
Prepare solutions (see Annex A) containing 10 % (or less) dry matter, according to the sensitivity of therefractometer, with compositions as close as possible to that of the samples to be analysed.
NOTESuitable reference materials for the constituents listed in Clause 1 can be obtained from establishedchemical companies.
4.3 Ion-exchange resins, for off-line demineralization of samples. Salts present in the sample will co-elute from the column, and will be detected by the refractometer, causing errors in the determination. These salts shall first be removed by ion-exchange resins. The most convenient way is to have an in-line guard column cartridge system (5.5), but this may also be carried out off-line using the following resins 1) :