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Biochemical FoodTest
Aslevel Biochemistry AQA Specification
| Nutrient | Reagent Used | How Test is carried out | Positive Result |
|---|---|---|---|
| Reducing Sugars | Benedict's Solution | Add Benedict's solution to sample in a test-tube. Heat in a water-bath. | Orange-Red |
| Non-Reducing Sugar | Hydrochloric acid, and Benedict's solution | Boil sample with dilute acid. Add sodium hydrogencarbonate to neutralise. Carry out reducing sugar test. | Orange-Red |
| Starch | iodine solution | Add few drops of iodine solution to the sample | Blue-Black staining |
| Lipid | Ethanol | Shake the sample with ethanol in a test-tube. Allow to settle. Pour clear liquid into water in another test-tube | Cloudy-White emulsion |
| Protein | Bieuret solution | Add biuret solution to sample in a test-tube. Warm very gently | Lila/mauve colour |