Benedicts test for reducing sugars

• grind up sample
• add Benedicts solution
• heat
• colour change from blue to red/brown indicate reducing sugars
• note simple non reducing sugars (mainly disaccharides) can all be hydrolysed to their reducing sugar components by heating with dilute acid (e.g. HCl). If you neutralise after heating you can then perform the Benedicts test
• a positive result indicates the presence of a simple non-reducing sugar

Iodine (I₂) test for starch

• add drops of Iodine to sample
• colour change from brown to blue black indicates presence of starch

Shultz's test for cellulose

• add Shultz's solution
• purple colour indicates presence of cellulose

Biuret test for protein

• grind up sample
• add Biuret solution
• lilac colour indicates protein present

Emulsion test for lipids

• grind up sample
• add ethanol
• decant into water
• cloudy emulsion indicates presence of lipid

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