Technical Talk – March 2011

Food allergens are still much on the minds of the food industry. There are a growing number of allergen-sensitive individuals who can suffer serious and severe reactions to certain foods. Consequences include sensitivity (adverse food reaction), intolerance (abnormal physiological response), hypersensitivity (immunologic reaction) and anaphylaxis (a severe and sometimes fatal reaction to food). Allergens are present in many ingredients and finished food products. In many cases cross-contamination in manufacturing plants can also affect non-allergenic foods.

Food allergens are still much on the minds of the food industry. There are a growing number of allergen-sensitive individuals who can suffer serious and severe reactions to certain foods. Consequences include sensitivity (adverse food reaction), intolerance (abnormal physiological response), hypersensitivity (immunologic reaction) and anaphylaxis (a severe and sometimes fatal reaction to food). Allergens are present in many ingredients and finished food products. In many cases cross-contamination in manufacturing plants can also affect non-allergenic foods.

This developing issue poses a challenge for the food industry as more individuals demand greater information about the food they eat. The manufacturing of food products is an intricate process requiring a plethora of ingredients which are themselves complex. Sometimes correct information about the contents of these ingredients is difficult to obtain or some of the components are not declared at all. In this situation the risk of contamination with allergens is very high. Because allergies can have as serious an implication as death, countries have introduced and continuously update regulations pertaining to common allergens.

Allergen regulations in Canada, which are currently in the process of being amended, recognize nine priority food allergens. They include peanuts, tree nuts, sesame seeds, milk, eggs, fish (including crustaceans), soy, wheat and sulphites. The general reference to tree nuts includes almonds, Brazil nuts, cashews, hazelnuts, macadamia nuts, pecans, pine nuts, pistachios and walnuts. The fish and crustaceans list contains crab, crayfish, lobster, shrimp, clams, mussels, oysters and scallops. The sulphites category includes many ingredients commonly used in foods such as potassium bisulphate, potassium metabisulphite, sodium sulphite. These nine allergenic core ingredients have to be declared on the ingredient label in Canadian food products.

Health Canada’s proposed amendments to food allergen labelling will enhance labelling requirements for specific priority allergens, gluten sources and added sulphites in prepackaged foods sold in Canada. In summary, the proposed changes will require:

• the specific tree nut and species of fish, crustacean or shellfish to be identified (rather than using the generic terms “tree nuts”, “fish”, “crustacean” and “shellfish”)
• a declaration of source when the food contains any gluten protein (from barley, oats, rye, triticale or wheat, including kamut or spelt);
• the addition of mustard seeds to the priority allergen list;
• the sources of hydrolysed plant proteins, starches and modified starches, and lecithins to be identified in the ingredient list;
• the declaration of the priority allergens (including sulphites present at levels of 10 ppm or more) even if the ingredient is exempt from component declaration and/or if the product is exempt from ingredient declaration (certain wines and beers).

Food regulatory agencies in other countries have their own regulations that we have to be aware when we are exporting food to these countries. The table below provides a list of the allergenic ingredients that have to be declared in United States, European Union and Japan as compared to Canada (including the proposed amendments).

Foods that cause allergic reactions have specific elements that are responsible. These are usually proteins and in some cases represent a very small specific peptide of these proteins. For example, beta-lactoglobulin, the main component of milk, is responsible for allergic reactions. Beta-lactoglobulin associated with whey, whey protein concentrates and isolates are widely used as ingredients in many food products including infant formula and baked goods. Casein is another protein in milk responsible for allergic reactions and it is a functional ingredient in the production of cheese. Some soy cheeses may also contain casein, which is used to enhance the texture. Egg whites contain most of the protein in eggs with four allergenic elements: ovomucoid, ovalbumin, ovotransferrin and lysozyme. The egg yolk allergenicity is not as severe as that of the egg whites.

Some allergenic reactions have been reported with wheat; however, the major concern relates to celiac disease. Celiac disease is an adverse reaction to certain proteins (prolamins) of wheat, barley, rye and other wheat-related grains such as spelt and kamut. These specific proteins are gliadin from wheat, hordein from barley and secalin from rye. Avenin, the protein in oats, is thought not to be involved. However, because of the harvesting, distribution and processing practices involved, it is hard to obtain pure oat products that are not contaminated with wheat, etc. Therefore, considering oats as free from non-allergenic ingredients is difficult. These cereal proteins adversely affect the sensitive individual by causing a modification of the lining of the intestine, thus affecting the absorption of nutrients. The number of individuals suffering from celiac disease is on the rise but some experts attribute this increase to a better diagnosis of the disease. The only treatment for celiac disease is a permanent gluten-free diet. In Canada, a gluten-free declaration means there is no detectable level of gluten in the food. The Codex Alimentarius currently defines gluten-free as those products containing less than 20 ppm. Gluten is the major functional protein that enables us to produce the desirable, quality baked goods we are accustomed to. It is still very difficult to produce gluten-free baked goods of the same quality as those produced from wheat flour.

There are certain practices that manufacturers can adopt to minimize the risk of contaminating finished foods with allergens. Sanitation and proper cleaning procedures are well adopted by the industry. Allergen detection technology is improving, becoming more accurate and faster with levels of recognition down to a few ppms and techniques like ELISA immunoassays and DNA detection. These techniques can be regularly performed on the ingredients to assure they are free of contaminants but in many cases can detect the allergens in finished foods as well.

The baking industry, like all other food manufacturers, needs to be very careful not to allow any undeclared allergenic ingredients in their finished products. This is always difficult. To overcome this challenge, the government is in consultation with the food industry and the different allergen groups to develop a precautionary labelling policy. This policy allows a statement on the food label to indicate that there is a possibility that the food may contain an allergen. For example the statement on the label can say “may contain peanuts.” This statement will inform the sensitive consumers and help avoid the risk of allergenic incidents.

Dr. John Michaelides is Guelph Food Technology Centre’s director of research and technology. This article was written in partnership with Daina Rye, allergen specialist with the GFTC. For more information, or fee for service help with product or process development needs, please contact the GFTC at (519) 821-1246 or by e-mail at gftc@gftc.ca