MadSci Network: Biochemistry |
Reducing substances, in cane sugar for example, are sometimes also refered to as invert sugar. Invert sugar, in cane syrup, are just the monosaccaride components of sucrose (glucose & fructose). Reducing substances, on the other hand, are any components that have active aldehyde ends or anomers that have the ability to reduce copper (Cu). Sucrose cannot be considered a reducing sugar because the 1-2 linkage of glucose and fructose leave no aldehyde site available. The test most commonly used to determine Reducing substances in the Sweetener food industry is the Lane-Eynon General Volumetric Method. You can find a copy of this method in the Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC), 15th Edition under Method Number 923.09 (I also have this method on a Word document that I can post if necessary). Basically it uses the reduction of copper (Cu) to determine the percent of Reducing Sugars in a sample. You can also determine sucrose under Method Number 930.36. The procedure used to determine the actual percentages of the two invert sugar monosaccarides, glucose and fructose, is High Performance Liquid Chromotography (HPLC). It can determine the actual percent of monosaccarides, disaccarides (sucrose), trisaccarides (maltotriose), and higher.
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