Food additives

• What are food additives?
• Coding of food additives
• Classification of food additives
• Looking for additives in foods
• Differences between natural and artificial colouring
• Are food additives safe to consume?
  • Aspartame
  • Benzoate
  • Monosodium glutamate
  • Nitrates
  • Sulphite
  • Tartrazine
• Sensitivity of individuals to food additives
• Useful tips for diagnosis and management

What are food additives?

Food additives are chemical substances added to foods to improve flavour, texture, colour, appearance and consistency, or as preservatives during manufacturing or processing. Herbs, spices, hops, salt, yeast, water, air and protein hydrolysates are excluded from this definition.
Confusion has arisen regarding whether or not vitamins and minerals are considered to be food additives. In Australia, Food Standards of Australia and New Zealand (FSANZ) classifies vitamins and minerals as a distinct set of food additives, and they are regulated separately in their own standard.For example, the fortification of vitamin C in fruit juice or calcium in milk products is aimed at improving the nutritional quality of food products.
Food additives can be extracted from natural sources. Vitamin C, or ascorbic acid, (300) is extracted from fruit, and lecithin (322) from egg yolks. Food additives can also be synthesised in a laboratory. Synthetic compounds from the laboratory either do not occur in nature, or are chemically identical to natural materials (known as nature-identical).
In many countries, the use of food additives is regulated, and food additives must be declared on food labels by using their chemical names or numbers. In Australia, food additives are assessed by FSANZ before they are allowed to be used.Before FSANZ approves the use of any new additive in a particular food, they ensure that:

• The additive is safe to consume (at the requested level in that particular food);
• There are good technological reasons for the use of the additive; and
• Consumers will be clearly informed about its presence.

If no adverse health effects are demonstrated on the requested use, FSANZ will approve the food additive and recommend a maximum level of food additive permitted in particular foods. Generally, food additives approved by FSANZ are safe to consume without any adverse reactions, however, some people are sensitive to particular food additives in common use.

Coding of food additives

The food additive coding system was developed by the European Community (EC). The European food additive code numbers are prefixed by ‘E’ (e.g. E223). These E-numbers indicate the food additives that are approved for use in Europe.
Countries outside Europe use the numbers but do not add the E prefix. For example, acetic acid is written as E260 on food products sold in Europe, but it is known as additive 260 in Australia. Additive 103, alkanet, is approved for use in Australia and New Zealand, but is not approved for use in Europe and so does not have an E number.

Classification of food additives

Different types of food additives and their functions are listed in Table 1.

Table 1: Classes of food additives

Class of additive	Function	Examples
Anti-caking agents	Keep powdered products (e.g. salt) flowing freely when poured	Bentonite (558), Calcium aluminium silicate (556), Calcium silicate (552)
Anti-foaming agents	Reduce or prevent foaming in foods	Polyethylene glycol 8000 (1521), Triethyl citrate (1505)
Antioxidants	Retard or prevent the oxidative deterioration of foods	Butylated hydroxyanisole (320), Ascorbyl palmitate (304), Calcium ascorbate (302)
Artificial sweeteners	Impart a sweet taste for fewer kilojoules/calories than sugar	Sorbitol (420), Alitame (956), Aspartame (951), Saccharin / calcium saccharin (954)
Bleaching agents	Whiten foods	Chlorine (925), Chlorine dioxide (926), Benzoyl peroxide (928)
Bulking agents	Increasing the bulk of a food without affecting its nutritional value	Ammonium chloride (510), Isomalt (953), Polydextrose (1200)
Colourings	Add or restore colour to foods	Curcumin (110), Brilliant blue FCF (133), Tartrazine (102)
Colour retention agents	Retain or intensify the colour of a food	Ferrous gluconate (579)
Emulsifiers	Prevent oil and water mixtures separating into layers	Lecithin (322), Sorbitan monostearate (491), Ammonium salts of phosphatidic acids (442)
Enzymes	Break down foods (e.g. ferment milk into cheese)	α-amylase (1100), Lipases (1104), Proteases (papain, bromelain, ficin) (1101)
Firming agents	Strengthen the structure of the food and prevent its collapse during processing	Calcium chloride (509), Calcium gluconate (578), Calcium sulphate (516)
Flavour enhancers	Improve the flavour and/or aroma of a food	Calcium glutamate (623), Disodium 5′-ribonucleotides (635), Ethyl maltol (637)
Food acids	Maintain a constant level of sourness in a food	Acetic acid (260), Citric acid (330), Fumaric acid (297)
Flour treatment agents	Improve flour performance in bread making	Sodium metabisulphite (223), Ammonium chloride (510), Potassium bromate (924)
Glazing agents	Impart a shiny appearance or provide a protective coating to a food	Beeswax, white and yellow (901), Carnauba wax (903), Shellac (904)
Gelling agents	Thicken and stabilize various foods (e.g. jellies, deserts and candies)	Agar (406), Calcium alginate (404), Carrageenan (407)
Humectants	Prevent foods from drying out (e.g. dried fruits)	Glycerin or glycerol (422), Lactitol (966), Oxidised polyethylene (914)
Mineral salts	Improve the texture of a food (e.g. processed meats)	Cupric sulphate (519)
Preservatives	Protect against deterioration caused by microorganisms	Sodium nitrate (251), Benzoic acid (210), Sodium benzoate (211)
Propellants	Gases which help propel a food from a container	Carbon dioxide (290), Nitrogen (941), Nitrous oxide (942)
Sequestrants	Bind and remove unwanted minerals that cause oxidation	Potassium gluconate (577)
Stabilisers	Maintain the uniform dispersion of substances in a food	Xanthum gum (415), Guar gum (412), Bleached starch (1403)
Thickeners	Improve texture and maintain uniform consistency	Tannins (181), Sodium alginate (401), Pectins (440)
Vitamins	Restore vitamins lost in processing and storage	B vitamins, including niacin Vitamin C Vitamin E

Looking for additives in foods

Food additives can be found in the ingredients list on the food label. Food labelling enables consumers to identify the presence of additives in packaged food and to make an informed choice about the foods they buy.
According to FSANZ, food additives are required to be identified by their class name, followed by an individual name or code number. To simplify the food labels, a code number is used to replace the individual name of the food additives. Food additives may be listed in food labels as, for example, thickener (guar gum) or thickener (412).
A list of food additives that are currently used in Australia can be found on the FSANZ website.

 Differences between natural and artificial colouring

Artificial or synthetic colours are synthesised in the laboratory. They can be chemically identical to colours that occurs naturally. Natural colours are derived from natural or biogenic sources (e.g. animal, vegetable or mineral). Both natural and artificial colours are used in food products like ice creams, confectionery, biscuits, sweet meats, fruit drinks, seasonings, pharmaceutical tablets and syrups.
The use of colour additives which might cause cancer or hyperactivity in children has raised concern among consumers. It is possible, but rare, to have an allergic-type reaction to a colour additive. For example, tartrazine (102) is an artificial colouring that has been associated with allergic reactions in some rare instances. Reactions have ranged from rashes and swelling to asthma, and possibly even to behavioural changes. Individuals should read food labels and avoid certain colour additives if they experience allergic reactions.

Are food additives safe to consume?

Although safety assessments of food additives are carried out by FSANZ before the food additives are approved for use, food additives can still induce adverse reactions in some sensitive individuals. According to FSANZ, it does recognise the adverse reactions to food additives in a small proportion of the population. These reactions are not the same as allergies, but may include rashes and swelling of the skin, irritable bowel symptoms, behavioural changes in children, and headaches.
Two major groups of food sensitivity are known as food allergy and food intolerance. Food allergies are abnormal immunologic responses to a particular food or food component. In contrast, food intolerances are non-immunologic responses. Generally, total avoidance of the culprit food is necessary for true food allergies. Food intolerances can be managed by limiting the amount of the food or food ingredient that is eaten. Total avoidance is usually not necessary for food intolerances.
Some commonly used food additives that tend to induce adverse reactions are:

Aspartame

Aspartame (951) is an artificial sweetener that is used to replace sugars in foods and beverages. The long term effects of aspartame on health have been studied intensively, but results were inconclusive. It is noted that aspartame induces carcinogenic effects in a dose-related manner. Contradictory results were shown in studies which reported that aspartame consumption in foods and beverages does not raise the risk of brain or other cancers.
Although inconclusive results were shown in several studies, FSANZ and other international regulatory agencies concluded that aspartame is safe to consume. Aspartame is approved for general use in tabletop sweeteners, carbonated soft drinks, yoghurt and confectionery.
The acceptable daily intake (ADI) of aspartame is currently 50 mg/kg body weight in the United States, and 40 mg/kg body weight in Australia and the European Union for both children and adults.

Benzoate

Sodium benzoate (211) is used as a food colouring and preservative in foods. Children who consumed a mixture of food colourings and preservatives from soft drinks and confectionery at high levels were found to be more hyperactive than those who did not have the colourings and preservatives. Colourings and preservatives can be minimised in diets by including lots of fresh fruits and vegetables and eliminating processed foods.

Monosodium glutamate (MSG)

Monosodium glutamate (621) is often added to food as a flavour enhancer but it can also occur naturally in food. While in the past MSG has been implicated as the causative agent of Chinese restaurant syndrome (CRS) and asthmatic attacks there is insufficient evidence to support this at the levels consumed in food.

Nitrates

Nitrates or nitrites are added as a preservative, antimicrobial agent or colour fixative to processed foods such as meats and cheese.Nitrate also occurs naturally in water, vegetables and plants. The human body converts nitrate in food into nitrite. Nitrite has been implicated in a variety of long term health effects, including gastric cancer.

Sulphite

Sulphite sensitivity is a food intolerant reaction.Sulphites exist in several forms (e.g. sodium and potassium metabisulphite, sodium and potassium bisulphite, sodium sulphite, and sulfur dioxide).Sulphite has many functions, including as a antimicrobial agent. It inhibits enzymatic and nonenzymatic browning, whitens foods, and serves as a dough conditioner.Manifestations of sulphite sensitivity include anaphylaxis and asthma.

Tartrazine

Tartrazine (102) is an approved artificial food colour. Tartrazine has been implicated in the aggravation of both asthma and chronic urticaria in some people. However, the association of tartrazine in the provocation of asthma and chronic urticaria is controversial. Some studies have shown a cause-and-effect relationship, whereas other studies have not. Both asthma and chronic urticaria are chronic illnesses with symptoms that tend to flare up at unpredictable times.

 Sensitivity of individuals to food additives

Food additives used in food products are approved by FSANZ. However, some individuals are sensitive to specific food additives. The degree of sensitivity varies from person to person.

Children

There has been a debate regarding the detrimental effect of artificial colours and preservatives on the behaviour of children. It has been suggested that artificial food colours and other preservatives may produce overactive, impulsive and inattentive behaviours in children. However, the sensitivity of each individual to artificial colours is different. Some children have positive changes of behaviour when artificial colours are eliminated from their diet, while others do not.
Children who have hyperactive or hyperkinetic behaviour are to a larger extent diagnosed with attention deficit hyperactivity disorder (ADHD).Although ADHD is normally present at birth and tends to run in families, a study showed that food additives also predispose school-aged children to hyperactive behaviours.A child with ADHD has difficulty focusing his attention or engaging in quiet passive activities, and has educational difficulties, especially in relation to reading.

Asthmatic individuals

Some food colours and preservatives (e.g. sulphite, tartrazine and MSG) can induce asthma. Therefore, asthmatic individuals should beware of these components in food products and beverages.

 Useful tips for diagnosis and management

1. Keeping a list of suspected foods allows easier identification of the culprit foods.
2. Record all foods consumed, and any symptoms that occur coincident with ingestion, in a food diary.
3. Showing the food diary to physicians will aid the diagnosis of adverse reactions to certain foods.
4. To confirm allergic reactions to certain foods, a skin prick test (SPT) or radioallergosorbent test (RAST) should be performed.
5. If the test confirms an allergic reaction, avoid the substance that caused it.
6. Read the food label carefully and beware of the allergenic agents in food products.

More information

For more information on food groups and components, see Types and Composition of Food.

For more information on nutrition, including information on nutrition and people, conditions related to nutrition, and diets and recipes, as well as some useful videos and tools, see Nutrition.

References

1. Hanssen M, Marsden J. The new additive code breaker: Everything you should know about additives in your food: Complete number guide for Australia and New Zealand. 2nd ed. Port Melbourne: Lothian; 1991.
2. A Dictionary of Food and Nutrition. 2nd ed. Bender DA. Oxford University Press; 2005.
3. Food Standard Australia New Zealand. Food additives [online]. 2007 [cited 2008 June 26]. Available from url:  http://www.foodstandards.gov.au/ foodmatters/ foodadditives.cfm
4. New Zealand Food Safety Authority. Identifying Food Additives [Booklet]. 2008 [cited 2008 July 3]. Available from url: http://www.nzfsa.govt.nz/ consumers/ chemicals-toxins-additives/ additives-booklet.pdf
5. Food Standard Australia New Zealand. Australia New Zealand Food Standards Code. Commonwealth of Australia: FSANZ; 2008.
6. Food Standard Australia New Zealand. Food additives: Alphabetical list [online]. 2007 [cited 2008 June 26]. Available from url: http://www.foodstandards.gov.au/ newsroom/ publications/ choosingtherightstuff/ foodadditivesalphaup1679.cfm
7. McCann D, Barrett A, Cooper A, Crumpler D, Dalen L, Grimshaw K, et al. Food additives and hyperactive behaviour in 3-year-old and 8/9-year-old children in the community: A randomised, double-blinded, placebo-controlled trial. Lancet. 2007; 370: 1560-7.
8. Chandler MJ, Neese M, Conroy ML, Davis AW, Durston S, Easter A, et al. Diseases: A Nursing Process Approach to Excellent Care. Springhouse: Lippincott Williams & Wilkins; 2006.
9. Shils ME, Shike M. Modern Nutrition in Health and Disease. Philadelphia: Lippincott Williams & Wilkins; 2006.
10. Weiss B, Williams HJ, Margen S, Abrams B, Caan B, Citron LJ, et al. Behavioural responses to artificial food colours. Science. 1980; 207(4438): 1487-9.
11. Delgado-Vargas F, Parades-Lopez O. Natural Colorants for Food and Nutraceutical Uses. Boca Raton: CRC Press; 2003.
12. The Cancer Council Western Australia. Cancer Myths [online]. 2008 [cited 2008 June 26]. Available from url: http://www.cancerwa.asn.au/ resources/ 0803_additives_factsheet.pdf
13. Food Standard Australia New Zealand. Monosodium glutamate: A safety assessment [online]. 2003 [cited 2008 June 26]. Available from url: http://www.foodstandards.gov.au/ _srcfiles/ MSG%20Technical%20Report.pdf
14. Loon AJ, Botterweck AM, Goldbohm RA, Brants HA, Brandt PA. Nitrate intake and gastric cancer risk: Results from the Netherlands cohort study. Cancer Letters. 1997; 114: 259-261.
15. Thomson B. Nitrates and nitrites dietary exposure and risk assessment. New Zealand: Institute of Environmental Science and Research Limited; 2004.
16. Food Standard Australia New Zealand. Aspartame [online]. 2003 [cited 2008 June 27]. Available from: http://www.foodstandards.gov.au/ newsroom/ factsheets/ factsheets2007/ aspartameseptember203703.cfm
17. Soffritti M, Belpoggi F, Tibaldi E, Esposti DD, Lauriola M. Life-span exposure to low doses of aspartame beginning during prenatal life increases cancer effects in rats. Environmental Health Perspectives. 2007; 115(9): 1293-7.
18. Lim U, Subar AF, Mouw T, Hartge P, Morton LM, Solomon RS, et al. Consumption of aspartame-containing beverages and incidence of hematopoietic and brain malignancies. Cancer Epidemiology Biomarkers Prev. 2006; 15(9): 1654-9.
19. Soffritti M, Belpoggi F, Esposti DD, Lambertini L, Tibaldi E, Rigano A. First experimental demonstration of the multipotential carcinogenic effects of aspartame administered in the feed to Sprague-Dawley rats. Environmental Health Perspectives. 2006; 114: 379-85.
20. Gallus S, Scotti L, Negri E, Talamini R, Franceschi S, Montella M, et al. Artificial sweeteners and cancer risk in a network of case-control studies. Annals of Oncology. 2007; 18: 40-4.
21. Weihrauch MR, Diehl V. Artificial sweeteners: Do they bear a carcinogenic risk? Annals of Oncology. 2004; 15: 1460-5.
22. Nordic Working Group on Food Toxicology and Risk Assessment. Nordic Food Additive Database [online]. 2004 [cited 2008 July 3]. Available from url: http://www.norfad.dk/