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What are the tests for reducing and non-reducing sugars?

Can someone tell me what the tests are for reducing and non reducing sugars??
Reducing sugars: Benedict's test. Should go from blue to red/orange/yellow

Non-reducing sugars: Benedict's test. No colour change. Hydrolyse with hydrochloric acid. Benedict's test again. If colour change this time then non-reducing sugars were present in the original solution.
Original post by surina16
Reducing sugars: Benedict's test. Should go from blue to red/orange/yellow

Non-reducing sugars: Benedict's test. No colour change. Hydrolyse with hydrochloric acid. Benedict's test again. If colour change this time then non-reducing sugars were present in the original solution.


Don't you have to then neutralise the solution with hydrogen carbonate (or some sort of alkaline substance?)


Posted from TSR Mobile
Reducing: Take liquid sample, mix in Benedict's solution, heat the mixture and observe colour change. Positive test is blue to green, yellow, orange and brick-red

Non-reducing: Do the reducing test, mixture should stay blue. Then hydrolyse with diluted hydrochloric acid (under heat) for about 5 mins. Neutralise the solution with sodium hydrogencarbonate or any other base until the pH reaches 7 (check with universal indicator). Re-test with Benedict's solution and a colour change towards brick-red means that the sugars tested were non-reducing.
Original post by Cluster1
Don't you have to then neutralise the solution with hydrogen carbonate (or some sort of alkaline substance?)


Posted from TSR Mobile


yeah aha i missed it out by accident, thanks for that :biggrin:

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