🍃Biology Food tests Flashcards
(8 cards)
1
Q
How do you test for (reducing) sugars
A
- Benedicts solution
- heat in water bath
- negative deep blue, spectrum depending on concentration up to (brick) red
2
Q
How to you test for lipids
A
- ethanol
- cloudy if positive
3
Q
How do you test for starch
A
- iodine
- blue black is pos and yellow/brown is negative
4
Q
Ho do you test for proteins
A
- biuret
- add food sample to a test tube and mix biuret A and B in with it
- pos purple neg blue
5
Q
What is Benedict’s for and what are its colours
A
- (reducing) sugars
- it is a spectrum from (deep) blue neg to brick red pos
6
Q
What is iodine for and what are its colours
A
- starch
- blue/black pos orange/yellow neg
7
Q
What is ethanol for and what are its colours
A
- lipids
- cloudy when pos clear when neg
8
Q
What is biuret for and what are its colors
A
- poteins
- blue neg purple(/mauve) pos
