Antioxidants in Food

People want to eat more healthily and this includes eating unsaturated and polyunsaturated fats rather than saturated animal fats. Unfortunately, unsaturated fats are more susceptible to oxidation.

Antioxidants are added to foods that contain unsaturated fats to make them last longer and prevent them from turning rancid . Processing techniques have also been developed to reduce the risk of oxidation. For example, many snack food manufacturers fry crisps under a blanket of steam to reduce the amount of oxygen that can get into the frying oil. This extends the life of both the oil itself and the crisps.

Photo of low-fat spread

Consumers now want foods containing more unsaturated and polyunsaturated fats

The range of antioxidants

The number of antioxidants available to the food technologist is small. Synthetic and natural antioxidants give similar performance and they are often used in combination. This gives a more effective action.

The table shows some typical antioxidants:

Antioxidant E-number Typical foods
Ascorbic acid (vitamin C) E300 Beers, cut fruits, jams, dried potato. Helps to prevent cut and pulped foods from going brown by preventing oxidation reactions that cause the discolouration. Can be added to foods, such as potato, to replace vitamin C lost in processing.
Tocopherols E306 Oils, meat pies. Obtained from soya beans and maize. Reduces oxidation of fatty acids and some vitamins.
Butylated hydroxyanisole (BHA) E320 Oils, margarine, cheese, crisps. Helps to prevent the reactions that break down fats and cause the food to go rancid .
Citric acid E330 Jam, tinned fruit, biscuits, alcoholic drinks, cheese, dried soup. Naturally-occuring in citrus fruits like lemons. Helps to increase the anti-oxidant effects of other substances. Helps to reduce the reactions that can discolour fruits. May also be used to regulate pH in jams and jellies.

Antioxidants and health benefits

There may be health benefits from the use of antioxidants. Oxidation reactions in the body could be linked to the build-up of fatty deposits that cause blockages in arteries that can cause heart attacks. Antioxidants may be important in preventing this and there could also be a link with the prevention of certain cancers, arthritis and other conditions. The picture is not yet clear and a great deal of research needs to be undertaken.