food tests

Question 1

benedicts test

Answer 1

test for reducing sugars

Question 2

positive test for benedicts

Answer 2

colour range from green to red

Question 3

iodine test

Answer 3

test for starch

Question 4

positive test for iodine

Answer 4

blue - black

Question 5

biruet test

Answer 5

test for proteins

Question 6

positive test for biruet

Answer 6

purple

Question 7

ethanol test

Answer 7

test for lipids

Question 8

positive test

Answer 8

white emulsion

Question 9

Describe a biochemical test to show that raffinose solution contains a
non-reducing sugar.

Answer 9

Heat with acid and neutralise;
2. Heat with Benedict’s (solution);
3. Red precipitate/colour

Question 10

Describe how you would test a piece of food for the presence of lipid.

Answer 10

Dissolve in alcohol, then add water and mix
2. White emulsion shows presence of lipid.

Question 11

A student carried out the Benedict’s test. Suggest a method, other than using a
colorimeter, that this student could use to measure the quantity of reducing sugar in a
solution.

Answer 11

Filter and dry (the precipitate);
2. Find mass/weight;