Biochemical tests Flashcards
1
Q
How do you test for reducing sugars?
A
Benedict’s reagent, heat.
Blue -> green -> yellow -> orange -> red
2
Q
How do you test for non-reducing sugars?
A
Need to break into monosaccharides first by adding dilute HCL and heating then neutralising with sodium hydrogencarbonate.
Benedicts as usual.
3
Q
How do you test for proteins?
A
Needs to be alkaline so add few drops of NaOH.
Then add copper(II) sulfate.
Positive test, colour change blue to purple.
4
Q
How do you test for lipids?
A
Shake with ethanol then pour into water.
More lipids = more milky.
5
Q
How do you test for starch?
A
Iodine dissolved in potassium iodide solution.
browney-orange to blue-black.
