Testing for Glucose and Other Nutrients
Benedict's test is your go-to method for spotting glucose in food samples. You'll heat 5cm³ of your food sample with 10 drops of Benedict's solution in a 75°C water bath for 5 minutes. The magic happens when the blue solution transforms - turning green or yellow for small amounts of glucose, or brick red for high concentrations.
For starch detection, the iodine test is brilliantly straightforward. Mix 5cm³ of your sample with a few drops of iodine solution and watch for the colour change. If starch is present, the browny-orange iodine will dramatically shift to blue-black.
The Biuret test reveals proteins by mixing equal amounts (2cm³ each) of your food sample and Biuret solution. Proteins will turn the mixture from blue to pink or purple - no proteins means it stays blue.
Safety tip: Always point test tubes away from yourself when heating, and use proper test tube holders to avoid burns.
