food test

Question 1

what is the basic method for preparing food samples

Answer 1

1) get piece of food and break it up
2) transfer to beaker and add distilled water
3) stir to dissolve some food
4)filter solution to get rid of solid bits

Question 2

what do you use benedict’s solution to test for

Answer 2

sugars

Question 3

what’s the method of testing for sugars using benedict’s

Answer 3

1) prepare food sample and transfer to test tube
2) prepare bunsen burner
3) add benedict’s to solution
4) place test tube in the heated water
5) leave for 5mins
6) if it contains reducing sugar it’ll turn form blue to green yellow or brick red

Question 4

what do you use iodine solution to test for

Answer 4

starch

Question 5

how do you test for starch using iodine

Answer 5

1) make a food sample and transfer to test tube
2) add few drops of iodine
3) gently shake to mix
4) if it contains starch the colour will change from browny orange to black or blue

Question 6

what do you use biurets solution to test for

Answer 6

proteins

Question 7

what is the method to test for proteins using biurets

Answer 7

1) prepare sample and transfer to test tube
2) add biurets and gently shake
3) if it contains protein it will change from blue to purple

Question 8

what do you use ethanol solution to test for

Answer 8

lipids

Question 9

what is the method to test for lipids using ethanol

Answer 9

1) prepare food sample but don’t filter and transfer to test tube
2) add 3 drops and gently shake
3) if the sample contains lipids the mixture will separate into two layers -bright red is top and clear on bottom