Food tests

Reducing sugars e.g. glucose food test

• Benedicts - blue

• Add and heat strongly

• Yellow - little sugar, Brick red - lots sugar

Nnn-reducing sugars e.g. sucrose food test

• Benedicts - blue

• Add hydrochloric acid to hydrolyse sucrose

• Add sodium hydroxide to neutralise

• Add and heat strongly

• Brick red

Starch food test

• Iodine - orange

• Blue/black

Protein food test

• Biuret - blue

• Lilac

Lipid food test

• Alcohol - clear

• Add and shake gently

• Milky white