Tests For Substances

Question 1

What is the test for starch?

Answer 1

Put chemical idoine on the substance, if it has starch it will turn from brown to blue black

Question 2

What is the test for protein?

Answer 2

Use biuret reagent, if there is protein then the solution should turn purple but if it’s blue there is no protein present

Question 3

What is the test for fats/lipids?

Answer 3

Rub a food sample onto a piece of filter paper, when you hold it up to the light, if there’s a translucent stain then there is fat.

Question 4

What is the test for sugar?

Answer 4

Place two spatulas of powdered food into a boiling tube. Add (about 1cm depth a) water to the tube and stir to mix. Add an equal value of Benedict’s solution and mix. Place the tube in a water bath (at about 95°) for a few minutes. It will turn orangey-red if there is sugar but will stay blue there’s not.