Break up the food with a pestle and mortar and and some to distilled water.
Stir it to dissolve some of the food.
Filter out the solid parts of the food.
Add 5cm3 of the food sample to a test tube.
Put it in a water bath set to 75C and add several drops of Benedict's solution.
Leave it in the water bath for 5 minutes with the test tube pointing away from you.
If it contains a reducing sugar it will turn from the normal blue colour to either green, yellow or brick-red depending on the amount of sugar in the food.
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Iodine test for Starch
Break the food up and add some distilled water.
Stir the mixture to dissolve some of the food.
Filter out the solid parts of the food.
Add 5cm3 of the sample to a test tube.
Add a few drops of iodine solution and shake gently to mix the contents.
If it contains starch it will turn from browny-orange to black or blue-black.
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Biuret Test for Proteins
Break up the food and add distilled water.
Stir the mixture to dissolve some food.
Filter out the solid parts of the food.
Add 2cm3 of the sample to a test tube.
Add 2cm3 of biuret solution to the sample and gently shake to mix it.
If it contains protein it will turn from blue to pink or purple.
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Sudan III test for Lipids
Break the food up and add distilled water.
Stir it to dissolve some of the food.
You don't need to filter it.
Add about 5cm3 to a test tube.
Add 3 drops of Sudan III stain solution to the test tube and gently shake it.
If it contains lipids it will separate into two layers with the top being bright red.
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