Antioxidants are added to preparations to increase the stability of oxidation-sensitive substances. There are water soluble and fat soluble anti-oxidants. In Annex, the anti-oxidants are listed with the corresponding concentration.
There oxidation reactions can be catalyzed by metal ions, chelators or metal binders can be added to enhance the action of antioxidants, for example after EDTA (0.05% à 0.10% m/V), citric acid, tartinic acid.
Table 1. Water soluble anti-oxidants
|
Antioxidant |
concentration (% m/V) |
pH |
|
Ascorbic acid (vitamin C) |
0.01%-0.50% |
pH < 7 |
|
After metabisulfite |
0.01%-0.20% |
Low pH |
|
After sulfite |
0.05%-0.15% |
High pH |
|
After bisulfite |
0.10% |
Neutral pH |
|
After thiosulfate |
0.05%-0.15% |
(for Jodiden) |
|
After formaldehyde-sulfoxylate |
0.10% |
|
Table 2. Fat-soluble anti-oxidants
|
Antioxidant |
concentration (% m/V) |
|
α-tocopherol (vitamin E) |
0.05%-0.10% |
|
BHA |
0.01%-0.02% |
|
BHT |
0.01% – 0.02% |
|
Propyl gallate |
0.10% |