Simple, rapid tests are a small investment with a big return

People who do not know someone with a food allergy may have little idea how life-threatening a food allergy can be, as well as how challenging it is to identify “safe foods” to eat. Consumers with food allergies rely on manufacturers to produce 100% allergen-free foods when labels do not identify allergenic ingredients. There are eight foods that account for 90% of reactions, with egg, milk and peanut among the most prevalent. Food processors cannot fail the more than six million Americans who are known to have a food allergy. For some of these people, consuming a minute quantity of an undisclosed food allergen means a call to 911.

What’s a food allergen?

Food allergens are proteins that trigger an immune response in allergic individuals.

Food manufacturers provide allergen protection by clearly labeling ingredients in a product, and flagging when a product definitely does contain, or may contain a known allergen. Testing for the presence of food allergens helps ensure safety in foods that do not declare them on ingredient statements. Rapid testing, in particular, may help prevent a recall if a contaminant is found in the food before it is in distribution. This is not to mention the loss of the millions of dollars often associated with a voluntary recall.

Because non-allergenic products and products formulated with an allergen are often made at the same facility, some processors would rather play it safe, and include precautionary disclaimers such as may contain peanut and peanut products. A company may be able to limit their use of such precautionary labels when they rapid test for allergens. Testing helps provide assurance against cross contact.

Why rapid test?

Rapid food allergen test kits enable food processors to quickly determine if an allergen-free food has been subject to cross contact with a food containing known allergens. Tests can be conducted on raw material before it enters production, or on equipment or product at any point during the manufacturing process. Testing clean-in-place (CIP) solutions and certain equipment after the sanitation crew has finished can identify sources of cross contact, and also verify cleanliness before changeover.

“Sanitation verification programs should be in place where shared equipment is used. Products where shared equipment is common include ice cream, soymilk, orange juice, sorbet, mixes, eggnog and bottled water, most products made at a dairy plant,” says Rob Soule, territory mgr., Neogen Corp., Lansing, Mich. “Products can be contaminated by residual proteins of one product being carried over to the next on shared equipment. Also, mislabeled ingredients or supplier quality issues can be contributing factors.”

Neogen supplies the food industry with sandwich enzyme-linked immunoassays (S-ELISAs) that rapidly test for the presence of egg, milk or peanut residue. All tests work on the same principle (see flow diagram): 1) A target food allergen protein is extracted from samples with a buffered salt solution. 2) Extracted protein is added to antibody-coated microwells, where it binds to the antibody during incubation. 3) Any unbound protein is washed away and a second antibody, which is enzyme-labeled conjugate, is added. 4) The conjugate binds to the already bound protein. 5) After a second wash, substrate is added, and color develops as a result of the presence of bound conjugate. 6) A stopping reagent is added and the color of the resulting solution is observed. A blue color indicates a strong positive. Red color indicates little to no target food allergen.

There are two test formats from Neogen.

“The Alert® format is designed to be a screening test whereas the Veratox® format is a quantitative test used to determine exact concentrations for finished product or ingredient verification,” says Soule.

John Van Arsdale, dir. of sales, adds, “Our kits were developed in conjunction with The University of Nebraska’s Food Allergy Research and Resource Program (FARRP). Tests are simple and rapid to use and therefore a dairy may run it in their lab, or send to an outside lab such as FARRP ( or Neogen for validation.”

Neogen will train plant personnel on how to properly use the tests. They also have a technical services lab for sample testing and 24-hour support.

“Startup costs are minimal,” concludes Van Arsdale. “A small investment to ensure consumers’ safety.”

Neogen, in conjunction with FARRP, has developed for the food and dairy industries a handbook entitled “Comprehensive Food Allergen Monitoring, ” which is available at no charge.