FOOD TESTS

Starch test: An experiment to demonstrate starch in a particular product. Adding iodine to a food substance and if the food turns to blue/black then food has starch.

Result product observation starch
Cracker
Black starch Crisp
Black
starch
Potato
Black starch Apple yellowish no starch
Banana
No colour no starch
Bread
black starch Biscuit black starch
Milk powder
No colour no starch

Title: Reducing sugar test (glucose): An experiment to demonstrate sugar in a particular product. Adding benedict solution to a food substance and if the food turns coloured then food has starch
Result
product observation sugar
Banana
orange a little sugar
Biscuit
Lime green a little sugar apple reddish a lot of sugar
Potato
Bluish a little sugar
Crisp
blue a little sugar
Milk powder blue a little sugar
Cracker
No change no sugar
Bread
Red/orange a lot of sugar

NON REDUCING SUGAR
Title: None reducing sugar: An experiment to demonstrate no sugar in a particular product. Adding hydrochloric acid and sodium hydroxide to a food substance and if the food turns to peachy then the food has no sugar.
Result
Product observation Sucrose solution
Positive (peachy)

Title: Protein test
Result
product observation Cracker
No colour
Crisp
No colour
Potato
No colour
Apple
No colour
Banana
No colour
Biscuit
No colour
Milk powder
Purple : contains protein

Title: FAT TEST
RESULT
Product observation Cracker
Turn cloudy
Crisp
Turn cloudy
Banana
Turn cloudy
Potato
Turn cloudy
Apple
No change
Biscuit
Turn cloudy
Milk powder
Turn cloudy
Bread
Turn cloudy

HOW TO ENSURE ACCURACY
The fresher the product the quicker the reaction occurs
Making the samples smaller help the reaction to be fast
The test tube was to be clean to prevent any unwanted particles in the test tube
The heater should have been on before we started the experiment
The solution must be enough which it’s been tested for
Make sure to add the right solutions when testing for different things example benedict solution when testing for reducing sugar
Make sure you don’t remove the test tube from the heater in the middle of the process.

CHROMATOGRAPHY
Yellow = 70.5 cm
Green = 1.8 cm
Solvent mark (chromatography solvent)= 2.5 cm
(Butanol + ethanol acid)
RF = distance moved by coloured spot Distance moved by solvent front
Green = 1.8 = 0.72 Range (xanthophyll/chromatography) 2.5
Yellow = 0.5 = 0.2 Range (unknown closet carotene) 2.5
When comparing the results obtained to the tabulated rf results, the rf results obtained was closet to