B2- Food Tests Flashcards
What is the first step in preparing a food sample for testing?
Get a piece of food and break it up using a pestle and mortar.
After grinding food, what should you add to the beaker?
Some distilled water.
What is the purpose of filtering the solution?
To get rid of the solid bits of food.
What test is used to detect reducing sugars in food?
Benedict’s Test.
What color does the Benedict’s solution change if reducing sugars are present?
Green, yellow, or brick-red.
What is the temperature setting for the water bath in the Benedict’s test?
75 °C.
What solution is used to test for starch in food?
Iodine solution.
What color change indicates the presence of starch when using iodine solution?
From browny-orange to black or blue-black.
Which test is used to detect proteins in food?
Biuret Test.
What color indicates the presence of protein in the Biuret test?
Purple.
What is the color of the Biuret solution if no protein is present?
Blue.
What test is used to check for lipids in food?
Sudan III Test.
What happens to the mixture if lipids are present in the Sudan III test?
It will separate into two layers, with the top layer being bright red.
How much food sample is needed for the Biuret test?
2 cm³.
Fill in the blank: To test for lipids, you add _______ to the food sample.
Sudan III stain solution.
