Question

When testing to determine the presence of lipids in food, which solution or reagent should be used?

Answer 1

The answer should be C, Sudan red solution.

Sudan red solution dissolves in lipids, which can show a color of orange/red if lipid is present.

On the other hand, Biuret solution/reagent is used to test for proteins, and it'll show a color or purple if protein is present.

Iodine solution is used to test for the presence of starch, and it'll show a blue black color if starch is present.

And lastly, Benedict's solution is used to test for reducing sugars, and it'll show a brick red color (or green as small amounts) if reducing sugars are present after heating under boiling water bath.