Some foods, food ingredients or components of an ingredient can cause severe allergic reactions in some people - this is known as anaphylaxis. Foods such as peanuts, tree nuts (e.g. cashews, almonds, walnuts),  shellfish, finned fish, milk, eggs,  sesame and soybeans and their products, when present in food, may cause severe allergic reactions and must be declared on the label however small the amount. Gluten is also included in this list but the caution is more for those with Coeliac Disease rather than allergy. Those who are wheat allergic must stay away from all wheat including gluten. In addition, foods containing sulphite preservatives must be labelled as containing sulphites if they have 10 milligrams per kilogram or more of added sulphites. This is the level that may trigger asthma attacks in some asthmatics. A food must have a warning statement where people may be unaware of a severe health risk posed by an allergen in a food. The only current warning statement is in relation to food containing the bee product: royal jelly which has been reported to cause severe allergic reactions and in rare cases, fatalities, especially in asthma and allergy sufferers.
‘May contain’ You’ll notice some labels say ‘may contain’ certain allergens, for example ‘may contain nuts’. This is put on by the manufacturer who may be concerned that, while nuts aren’t added to the food, traces may be present due, for example, the product having been made on the same equipment as products containing nuts. Allergy consumer support groups are working with the food industry to make these labels more helpful to allergy sufferers.
Other names for major allergens Sometimes ingredients derived from peanuts, tree nuts, shellfish, finned fish, milk, gluten, eggs and soybeans are not clearly identified in the ingredients list, for example soy might be listed as ‘ textured vegetable protein’.  Allergy consumer groups are working with the food industry on industry guidelines to assist them in providing more meaningful information in plain English. [ continued ]
For more information on food allergies see Anaphylaxis Australia website http://www.allergyfacts.org.au or  Allergy New Zealand  http://www.allergy.org.nz/. Useful Information - Allergen Cards