Non-reducing sugars must first be hydrolysed before using the Benedict's test.The sample (if not liquid) is ground up in water and filtered. 2cm3 of the filtrate is added to 2cm3 of dilute hydrochloric acid and placed in a gently boiling water bath for 5 minutes. Sodium hydrogen carbonate solution is slowly added to neutralise the solution. The solution is tested with pH paper to ensure it is alkaline.The Benedict's test for reducing sugars is then carried out.
Test for Non-reducing Sugars
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Specification: AQA Biology (7401), AS-level, 3.1.2 Carbohydrates. Topic: Biological Molecules.
Key terms in this lesson
- hydrolysis
- The breaking of a covalent bond within a molecule using a water molecule.
- reducing sugar
- A sugar that can donate electrons and so reduces Benedict's reagent, forming an orange-red precipitate on heating.
More in Biological Molecules
- Carbohydrates
- Monosaccharides
- Test for Reducing Sugars
- Disaccharides
- Polysaccharides
- Starch
- Test for Starch
- Glycogen
All 29 lessons in Biological Molecules · All AQA AS-level Biology topics