food tests

• sugar - benedicts test: add Benedicts solution to sample, if sugar present, colour will change from blue to brick red
• startch- iodine solution: 10-20 drops of iodine solution colour of solution will turn from browny-oragne to blue-black
• proteins- biuret test: add biuret solution to sample, if present, it will change from blue to purple
• lipids - sudan III test: add 1cm3 of lipids to 1cm3 of iodine solution solution will stain lipids and mixture will separate into two layers: the top layer red if lipids present