Classes of Food Nutrients
| Test | Reagent | Observation | Conclusion |
| Benedict’s test | Food sample + Benedict’s solution (Place in boiling water bath) | The solution turns from blue to green / yellow / brick-red precipitate formed (depend on sugar concentration). | Food sample contains reducing sugar |
| Benedict’s test | Food sample + Benedict’s solution + Dilute hydrochloric acid (Place in boiling water bath) + neutralise by sodium hydrogen carbonate powder | The solution turns from blue to green / yellow / brick-red precipitate formed (depend on sugar concentration). | Food sample contains non-reducing sugar |
| Iodine / Starch test | Food sample + Iodine solution | The solution turns from brownish-yellow to blue-black. | Food sample contains starch |
| Emulsion test | Food sample + ethanol | The fat droplets formed on the surface and the solution become cloudy. | Food sample contains oil (lipid) |
| Sudan III test | Food sample + Sudan III stain | A red-stained oil layer separates out and float on the water surface | Food sample contains oil (lipid) |
| Fat test | Food sample + filter paper | A translucent mark formed | Food sample contains oil (lipid) |
| Millon’s test | Food sample + Millon’s reagent + 1% sodium nitrite (Place in boiling water bath) | The solution turns brick-red precipitate. | Food sample contains protein |
| Biuret test | Food sample + 20% sodium hydroxide solution and 1% copper(II) sulphate solution | The solution turns from blue to purple colour. | Food sample contains protein |
