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    Hi, can someone please help me out on what the food tests are for proteins, lipids, reducing sugars and non reducing sugars please? Like if a question were to ask:

    Describe how you would test the presence of a protein/lipid/reducing sugar/non reducing sugar.

    How would you answer it? It hasnt really been covered well in class and the WJEC biology guide isnt much help either.

    Thanks
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    Test for Starch - Iodine Test
    Add Iodine Solution Postive Result:Blue/Black Negative Result:Brown

    Test for Protein- Bieuret
    Add Biuret Positive result: Purple/Lilac Negative Result: Light Blue

    Test for Lipids- Ethanol emulsion Test
    Reagent: Ethanol and Water Positive Result: Cloudy white emulsion Negative Result:Clear

    Test for Reducing Sugars :Benedicts Test

    Add Benedicts reagent and HEAT - positive result from blue to a brick red precipitate produced

    Test For Non Reducing Sugars

    1) Carrying out the benedicts test will produce a negative result if only non reducing sugars are present
    2)HEAT with acid- hydrolyses glycosidic bond between glucose and fructose
    3) Neuralise with Sodium Hydrogen carbonate
    4)Add Benedicts solution and HEAT- positive result produced due to presence of the non reducing sugar glucose

    Hope that Helps!
    All the best
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    thank you so much!
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    I dont want to sound rude or a brain box and I may be wrong, but should point number four for say a positive result is now gained due to the reducing (not non-reducing) sugar glucose
 
 
 
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