the chemicals within carbohydrates and lipids and testing for chemicals in food samples Flashcards
what solution is used for testing for proteins and what is the colour change that occurs if proteins are present?
Biuret solution and it goes from blue to purple.
Extra info: add a sample of the food and mix it in and wait.
What solution is used for testing if sugars are present and what are the colour changes it undergos?
Benedict’s solution and depending on the concentration of sugar (from weakest to strongest) blue (none), green, yellow, orange, red.
Extra info: heat up the Benedict’s solution and then mix in the substance to test.
What substance is used to test for lipids and what is the tell for whether it is present?
Ethanol is used and if there is any lipids present they will float to the top in a cloudy solution.
Extra info: Add ethanol then the water and then the food.
What substance is used to test for starch and what are the signs of it being present?
Iodine - orange to blue/black
Extra info - place drops on the substance on a spotting tile.
