Food Tests

Test	Tests for	Positive Result	Method
Iodine	Starch	Turns Blue-Black	Add a drop of iodine to food solution
Biuret (CuSO4 + NaOH)	Protein	Turns Purple-Lavender	Add a few drops of copper sulphate (CuSO4) and sodium hydroxide (NaOH) to food solution
Benedict’s Solution	Sugar	With heat turns Brick-Red precipitate	Add a few drops of Benedict’s to food solution and heat gently of a bunsen
Ethanol Emulsion	Fats	White Emulsion	Add 2ml of ethanol to food solution and shake/mix, then add 2ml of water to solution and shake/mix
DCPIP	Vitamin C	Turns Colourless	Add a few drops of DCPIP to food solution and shake/mix then wait (NB: will turn pinky due to the presence of acid - false positive)