Anitoxidants

Substances that inhibit oxidation

An example of an oxidation reaction with atmospheric oxygen as the oxidizing agent is when a cut apple goes brown. By adding lemon juice, which contains vitamin C, a natural antioxidant, it is possible to delay the browning process.

Many types of fruit and vegetable contain natural antioxidants such as vitamin C, vitamin E and some carotenoids.

Antioxidants are also produced artificially and used as additives. They are used e.g. to prevent fruit juices going brown, to retain flavour in food and to prevent fats from going rancid.

‘Free radicals’, which are formed for instance by the effect of the sun’s UV rays, have a powerful oxidizing effect. They are often cited as a cause of cancer. Antioxidants act as radical traps, i.e. they prevent free radicals from reacting with proteins or other molecules, thereby preventing their destruction.