What are preservatives?
Preservatives are synthetic or natural chemicals added to foods to extend their shelf-life. Preservatives prevent or slow down the growth of microorganisms, like mould or bacteria, which can spoil food or make you ill.
The most widely used preservatives are:
- sulphites, including sulphur dioxide
- sorbates, including sorbic acid
- benzoates (including benzoic acid).
Foods that contain preservatives
The main food sources for these preservatives are:
- sulphites – in sausages, soft drinks and cordials, hamburger patties, and dried apricots. For adults, wine and beer are also major sources
- sorbates – in orange juice, margarine, and baked goods like cakes, muffins, pikelets and crumpets
- benzoate – almost solely from soft drinks.
Use of preservatives regulated
As with all food additives, the use of preservatives is regulated by the Food Standards Australia New Zealand (FSANZ). Preservatives can only be added to specified foods, and can't exceed the maximum permitted level (MPL) given in the Australia New Zealand Food Standards Code.
Most New Zealanders eating safe levels
While the MPL limits how much preservatives manufacturers can add to a food, the acceptable daily intake (ADI) tells you how much of a specific food additive you can safely eat each day, over the course of your life.
MPI and FSANZ studies of sulphites, sorbates and benzoates in Australia and New Zealand, combined with snapshots of everyday diet, have shown preservative levels within safe limits. While a small number of people were eating very large amounts of foods containing preservatives, most New Zealanders' intakes were well below the ADI.
Some children and young people eating above ADI
A small number of children up to 5 years of age, and boys up to 12 years of age had eating patterns that meant their intake of benzoates and sulphites were above the ADIs. But because ADIs are set with a high safety margin, it's unlikely this level of consumption poses a health risk.
You can reduce any potential risk to your children by limiting their intake of foods and beverages with high preservative levels.
Overall, given the large safety margin built into ADIs, preservatives are unlikely to be a health risk, unless you're allergic to sulphites.
Allergy or asthma reactions to sulphites
Sulphites may cause asthma-like symptoms in those who have asthma or chronic allergic conditions. In rare cases, people may react to sorbates and benzoates.
If you have an allergy to sulphites, sorbates or benzoates, check product labels to reduce your risk.
Find out more about food allergies
Food labels must list preservatives
All food additives, including preservatives, must be listed on food labels. They must be listed by function and their name or international code number. For example, preservative (sorbic acid) or preservative (200).