bio food tests

test for protein

Biuret test

test for lipids

Emulsion test

test for starch

Iodine solution

test for glucose

benedict test

how to prepare a food sample

1. food into mortar, grinnd with pestle

2. add water and mix

3. filter paper into funnel

4. filter into small beaker

biuret test steps

test for proteins

1. prepare food sample

2. add 5ml biuret solution

3. mix

4. observe colour change

5. record result

biuret test results

negative: blue

positive: purple

emulsion test steps

test for lipids

1. add small spatula of food sample into test tube

2. add 5ml ethanol and shake

3. add 5ml water and mix

4. observe results

emulsion test results

negative: cloudy white

positive: clear

benedicts test steps

test for glucose/sugars

1. prepare food sample

2. add 5ml food sample into test tube

3. add 5ml benedicts solution

4. place in water bath at 80degress

5. observe colour change after 10 mins

benedicts test results

negatiive: blue

low: green/yellow

medium: orange

high: brick red

iodine solution steps

test for starch

1. prepare food sample

2. add food sample into spotting tile

3. add 2-3 drops of iodine solution onto sample

4. observe colour change

iodine solution results

negative: orange-brown

positive: blue-black

what are monomers

single simple units

what are polymers

chains of monomers

what lipids are made of

glycerol and 3 fatty acid tails