Food tests Flashcards
(10 cards)
What test do we use for Glucose?
Benedict’s test
What type of molecule is glucose?
Carbohydrate
How is the Benedict’s test used to test for glucose?
Prepare a food sample in a test tube then add Benedict’s solution. Add the tube to a warm water bath for 5 minutes. If sample contains glucose, solution will turn from blue to green/yellow in low concentrations or red in high concentrations
What solution do we use to test for starch?
Iodine
What type of molecule is starch?
A complex carbohydrate
How is iodine used to test for starch?
Add a food sample to a test tube then add iodine and gently shake. If sample contains starch it will turn from browny-orange to black/blue
How do we test for proteins?
Using the Biuret test
How is the Biuret test used to test for protein?
Prepare a food sample in a test tube then add Biuret solution to the sample and gently shake to mix the contents. If it contains protein it will turn from blue to pink/purple
What solution do we use to test for lipids?
The Sudan III stain solution
How is the Sudan III stain solution used to test for lipids?
Prepare a food sample in a test tube and add a few drops of the Sudan III stain solution and gently shake to mix. If the sample contains lipids then the mixture will separate to 2 layers - the top layer will be bright red