From: Food Quality & Safety magazine, April/May 2009

Protect Your Company From Food Allergens

Learn how to test for allergens and protect your reputation

by Arlene K. Schag

He was 12 years old when he ate his last meal. He did not know what anaphylactic shock was, but that’s what happened to him after traces of peanut in his food triggered a severe immune response.

His lungs were transplanted into a 42-year-old female with no prior history of peanut allergy. Seven months after the transplant, she suffered anaphylactic shock after eating a peanut butter cookie. She survived but suffered a second anaphylactic shock later that same year. After doctors questioned her, she recalled that the first episode had occurred four days after the transplant. Skin prick testing confirmed sensitization to peanuts. This kind of peanut allergy transfer from donor to recipient has also been described after liver transplantation.

Food allergies happen when a person’s immune system reacts to proteins in what he or she has eaten. In an attempt to protect the body, the immune system produces antibodies to that food. Those antibodies then cause mast cells—allergy cells in the body—to release chemicals, one of which is histamine, into the bloodstream. Histamine then acts on a person’s eyes, nose, throat, lungs, skin, or gastrointestinal tract, causing the symptoms of the allergic reaction.

According to the Food Allergy & Anaphylaxis Network (FAAN), one in 25 adults and one in 17 children have food allergies. Statistics like these indicate a need for reliable manufacturing practices such as testing and proper labeling.

Allergic Reactions

Once an allergic reaction begins—a true food allergy, not a food intolerance—it is impossible to predict how severe it will become. It has been observed that an allergy that persists into teenage or adult life is less likely to disappear. explains how the timing and location of an allergic reaction depend on the complex process of digestion. For example, a person who is allergic to a particular food may first experience itching or tingling in the mouth. After the food is digested, abdominal symptoms such as vomiting, diarrhea, or pain may ensue. When the food allergens enter and travel in the bloodstream, they can cause a drop in blood pressure. Allergens reaching the skin can trigger hives or eczema; when they reach the lungs, they may cause asthma. These symptoms may occur within minutes, or they may take hours to start.

People who have a food allergy may also experience anaphylaxis, a severe allergic reaction that causes swelling of the mouth, throat, and airways leading to the lungs that results in an inability to breathe. In addition, anaphylaxis causes a dangerous drop in blood pressure, which can not only make someone dizzy or pass out but may quickly lead to shock and death. There is no medication in any form that can be taken before eating a certain food that will reliably prevent an allergic reaction to that food. The main treatment, injectable epinephrine, must be carried at all times.

Helpful Laws

The Food Allergy and Anaphylaxis Management Act (FAAMA), passed by the United States House of Representatives in April 2008, is an important bill that calls for creation of a uniform guidance document to help schools manage food allergies. The bill will direct the Secretary of Health and Human Services to develop a voluntary policy for schools to implement measures to prevent exposure to food allergens and to ensure a prompt response if a child suffers a potentially fatal anaphylactic reaction. The Senate Committee on Health, Education, Labor, and Pensions is to consider the bill within the coming months.

Some schools have responded to the dangers posed by food allergies by banning the major allergy-causing foods, creating, for example, so-called peanut-free zones. Unfortunately, until the peanut police can pat down every child and helpful laws can take effect, schools are limited in their ability to protect students.

Another helpful law is the Food Allergen Labeling and Consumer Protection Act (FALCPA), which requires that foods containing proteins from a “major food allergen” declare the presence of the allergen on the label. To make safe products, food companies must keep informed about these allergens, methods of testing, and quality control. According to the FAAN, milk, eggs, peanuts, tree nuts, wheat, soy, fish, and shellfish are responsible for 90% of all food-allergic reactions in the United States.

Milk Allergen

Human infants can develop an allergenic response to cow milk proteins. Beta-lactoglobulin is the major whey protein in ruminants and pigs. It is the primary antigenic component that stimulates immune hypersensitivity response. Symptoms of milk allergy may appear similar to lactose intolerance, so it is important to distinguish between them. Lactose intolerance is quite common and may cause gasiness, bloating, and diarrhea.

Small amounts of milk protein passing through the breast milk may cause allergic signs and symptoms in some infants. Cow’s milk allergy affects anywhere from 2% to 7.5% of infants. Goat’s milk is tolerated by only 40% of children who are allergic to cow’s milk.

The two main components in milk are whey and casein; an individual may be allergic to either or both. Casein is the curd that forms when milk is left to sour, and whey is the watery fraction that is left after the curd is removed. The whey proteins are altered by high heat, so the whey-sensitive person may be able to tolerate evaporated, boiled, sterilized, and powdered milk.

Usually, reactions occur upon the intake of moderate to large amounts of cow’s milk. Allergic reactions to milk can be described according to three types:

Type 1: Symptoms such as skin problems, eczema, or hives start within minutes of intake of small volumes of cow’s milk. May involve respiratory (runny nose, wheezy chest) or gastro-intestinal symptoms.

Type 2: Symptoms, including vomiting and diarrhea, start several hours after intake of modest volumes of cow’s milk.

Type 3: Symptoms, including diarrhea with or without respiratory or skin reactions, develop after more than 20 hours or days after intake of large volumes of cow’s milk.

With a doctor’s supervision, removing milk products from a child’s diet can help determine if they are causing illness. A dietitian can help to determine which calcium supplements or other food products will best substitute for milk. Because milk may be present in foods where it is least expected, even strict avoidance may not be enough to prevent allergic reactions. The prevalence of milk products underscores the need for clear, accurate testing and labels on food.

Egg Allergen

A frequent cause of food hypersensitivity in infants and young children are hen’s eggs. For people who are especially sensitive to eggs, even fumes in the air or egg on the skin can cause an anaphylactic reaction; in these cases, it is best to keep eggs out of the home completely.

Research has shown that ovomucoid, comprising 11% of the egg white protein, is the dominant antigen and allergen in egg white protein. These properties make ovomucoid a suitable marker protein for testing the presence of egg residues (egg whites) in food products. It appears to be allergenic in minute quantities, and, because of its hardy physical characteristics, it may remain in the body for years as an allergenic condition. Because of the high risks of cross contamination associated with egg—and its long-lasting potency—it’s an important allergen that should not be overlooked by food manufacturers.

Soy Allergen

Although the incidence of allergy to soybean proteins is quite low in comparison with other major food proteins, the gradually increasing consumption of soybean products encourages investigation. Soy allergy is more common in infants than in older children or adults. The average age at which the allergy manifests is three months, but the majority of infants outgrow it by the age of five. Adults do suffer from soy allergy, but it is rare.

Delayed allergic responses to soy, while less dramatic, are more common. These are caused by antibodies and occur anywhere from two hours to days after the food is eaten.

For food products that usually contain soy or are manufactured on machines that may have soy residue on them, the way that the soybean is grown, harvested, processed, stored, and prepared in the kitchen can all affect allergenicity. Soy is hidden in thousands of everyday foods, cosmetics, and industrial products, including inks, cardboard, paints, cars, and mattresses, making detection of soy residue during food manufacturing and handling an important goal.


The more a population consumes a certain type of food, the higher the chances are of people becoming allergic to it. According to the advocacy group, fish allergies affect approximately 20% of the population in countries in which fish is a staple of their diet. Food manufacturers in countries with increased fish allergies would benefit from implementing fish-specific safe handling processes and testing.

Spoiled fish may cause symptoms similar to an allergic reaction, due to the presence of histamine. Unlike a true allergy, however, this would affect the majority of the people who had eaten the same food. Eating fish that have consumed toxic algal blooms may also cause adverse reactions that are not allergy related.


Shellfish are aquatic invertebrates, not actually fish. People who are allergic to shellfish may be able to eat fish—and vice versa—unless they have allergies to both. Shellfish can be divided into two main categories: crustaceans and mollusks. Just breathing in airborne particles of shellfish in open fish markets can cause an allergic person to go into anaphylactic shock.

A person who is allergic to shellfish may also have to avoid certain products made from the shells or skeletons of these animals. Glucosamine, for instance, which is used to treat arthritis, is derived from the skeletons of shellfish. Some calcium supplements may contain ground oyster shells. Moisturizing lotions may contain shellfish-derived chitin. Unfortunately, non-edible products are not yet required by law to list possible allergens on their labels, even though consumers do depend on such information.


Wheat is widespread in foods, according to the advocacy group Some people with wheat intolerance or an undiagnosed allergy may feel much better after reducing or eliminating foods with wheat or gluten. Gluten is the molecular structure that holds the gas in bread, giving it its characteristic airy texture. Wheat contains many proteins, of which gluten is only one. A person can be allergic to wheat and not to gluten.

Gluten allergy is rarely suspected and, if not treated, can cause a wide range of illnesses such as indigestion, flatulence, stomach pain, asthma, depression, and epilepsy. Even with all these symptoms, a person lacking a proper doctor’s diagnosis may not realize breakfast cereal—among many other foods—is to blame.

Tree Nut

It is important to distinguish between tree nuts and peanuts. Tree nuts are classified as those that grow on trees, such as walnuts, pecans, chestnuts, and pistachios. Peanuts grow in the ground and are considered legumes like beans and peas. Seeds like pumpkin and sunflower are not tree nuts, though they are occasionally used as substitutes for tree nuts and peanuts because they provide a lot of nutritional value and are considered similar in taste. Sesame seeds are a little more risky, because they are considered one of nine major food allergens by the Canadian Food Inspection Agency.


Peanuts and tree nuts account for the majority of severe and fatal reactions and are widely considered to be lifelong allergies. According to the Department of Allergy and Immunology at the Royal Children’s Hospital in Melbourne, Australia, the most common triggers of anaphylaxis in children are peanuts (18%) and cashew nuts (13%).

Statistics indicate a rise in peanut allergens: About one in 70 children is now allergic to peanuts, compared to about one in 200 in 1992. Experts still do not agree if eating peanuts during pregnancy will increase or decrease the child’s risk, but if there is a family history of allergies it may be wise to avoid them until testing can be done.

Meanwhile, scientists are screening thousands of peanut varieties in a quest to find some that lack the allergen ingredients. Research is being done to genetically engineer allergen-free peanuts. Studies are trying to shine a light on how to predict which children will be among the 20% who grow out of the allergy. Some clues have been found using the size of the hives that form on the skin, but no reliable predictions can yet be made.

Testing Options

Food manufacturers and processors must rely on accurate, affordable testing to identify allergen risks. Food allergen detection tests are available to give companies the proof of performance they need.

  • SafePath Laboratories offers food allergen test kits to detect milk, soy, and egg residue, along with foodborne bacteria and parasites, within two and a half hours. Kits are sized differently to include lower volume situations and larger volume laboratories that may use some degree of automation.
  • The BioKits Gluten Assay Kit is suitable for use in the detection and quantification of gluten at very low concentrations in both uncooked and cooked foods, as well as in environmental samples. Food samples are extracted with a specially formulated buffer, then diluted and tested in the assay.
  • Genon Laboratories carries a wide range of test kits, including one that detects crustacean, shellfish, and mollusk residue. The company has also just completed development and validation of their new 9-Nut DNA Screen, which is designed to detect most nuts. Available individually or in packs of 20 swabs at low cost, these swabbing kits include all you need to take environmental samples that you can return to Genon Laboratories for quantitative or qualitative analysis.

It is important to take care of small problems before they multiply. Testing helps improve consumer confidence and company reputations. As food allergies become more common, it will take the skills and dedication of experts in the food industry to help meet the population’s demand for trustworthy food.

Schag wrote this article while employed at IVD Research Inc./SafePath Laboratories LLC. For more information go to or call (760) 929-7744.



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