Food Allergens

Strip Test TO DETECT ALLERGENS

-Complexes between anti-allergen antibody-coated colored beads with allergenic proteins in the sample and anti-allergen antibodies on the test strip -Give rise to colored test lines

Allergenicity An Immunological Response

1. Person is exposed to an antigen 2. Body produces IgE antibodies 3. Antibodies bind to mast cells, making them sensitive to future exposure 4. After secondary exposure to antigen, mast cells release chemicals that initiate an allergic response

Immunology Screening Methods

Biosensors Microsphere-based flow cytometric systems

Chemical Contaminants

Chemical contaminants can be present in foods mainly as a result of the use of agrochemicals, such as residues of pesticides and veterinary drugs, contamination from environmental sources (water, air or soil pollution), cross-contamination or formation during food processing, migration from food packaging materials, presence or contamination by natural toxins or use of unapproved food additives and adulterants.

Immunology Screening Methods FOR ALLERGENS

Detect trace amounts (mg/kg) in foods -Multiple allergen testing Goal is for all 8

Contaminants

Food contamination is generally defined as foods that are spoiled or tainted because they either contain microorganisms, such as bacteria or parasites, or toxic substances that make them unfit for consumption. A food contaminant can be biological, chemical or physical in nature, with the former being more common

Allergen Control Denaturation

Heat or chemicals can be used to denature protein allergen

Allergen Detection

Incoming raw materials • Swabs of food contact surfaces • Clean-in-place solutions • Push-through product • Final product

Unknown Contaminants

It requires expertise and a good analytical strategy • Based on all gathered information about the sample and potential sources of contamination. • Any clues, such as changes in smell, taste or texture, as well as a description of potential poisoning symptoms may be important in this respect. • Concurrent analysis of control ("good") samples with suspect samples is often essential to find differences and eliminate potential false positives. • Non-targeted analysis • Consider multiple extraction and separation assays

Food Allergen Labeling and Consumer Protection Act of 2004

Manufacturers must clearly identify on labels if ingredients contain one of the eight major allergens (milk, eggs, fish, shellfish, peanuts, tree nuts, wheat, soy)

Microsphere-based flow cytometric systems

Microsphere-based flow cytometric systems -Based on the flow cytometry detection of sets of differently colored micron-sized beads -Each color is bound with different antibodies for different allergenic compounds -Fluorescently labeled to visualize the binding -Laser scans to analyze quantity

Analysis of chemical contaminants

Most known chemical contaminants in foods are small organic molecules. Except for high-level adulterants, they are typically present in foods at low concentrations (parts per trillion to parts per million); thus, their analyses in complex food matrices are often quite challenging. The basic analytical approach involves an extraction using a suitable solvent, cleanup to remove interfering matrix components, a chromatographic separation and a selective detection. MS, GC-MS, LC-MS, with MS/MS

Does FALCPA require food manufacturers to label their products with advisory statements, such as "may contain [allergen]" or "processed in a facility that also processes [allergen]?"

No. FALCPA does not address the use of advisory labeling, including statements describing the potential presence of unintentional ingredients in food products resulting from the food manufacturing process. FALCPA does require FDA to submit a report to Congress, a part of which assesses the use of, and consumer preferences about, advisory labeling. In earlier guidance, FDA advised that advisory labeling such as "may contain [allergen]" should not be used as a substitute for adherence to current Good Manufacturing Practices (cGMPs). In addition, any advisory statement such as "may contain [allergen]" must be truthful and not misleading.

Is a major food allergen that has been unintentionally added to a food as the result of cross-contact subject to FALCPA's labeling requirements?

No. FALCPA's labeling requirements do not apply to major food allergens that are unintentionally added to a food as the result of cross-contact. In the context of food allergens, "cross-contact " occurs when a residue or other trace amount of an allergenic food is unintentionally incorporated into another food that is not intended to contain that allergenic food. Cross-contact may result from customary methods of growing and harvesting crops, as well as from the use of shared storage, transportation, or production equipment.

allergen control

Prevention of Cross-Contamination • Good Manufacturing Practices (GMPs) • Utilize dedicated utensils, equipment • Sanitation Standard Operating Procedures (SOPs) • Raw material Certificate of Analyses (COAs) • Rework

ELISA TO DETECT ALLERGENS

Proteins of the allergenic compound are detected by a specific enzyme-labeled antibody -Forms a colored product produced by an enzymatic reaction -Read with a spectrophotometer

Biosensors

Surface Plasmon Resonance (SPR) -Based on the changes in refractive index on the surface of a senso chip -Caused by the binding of an analyte to an immobilized ligand

Allergen labeling requirements

To comply with allergen labeling laws and to protect their own reputation and business, food producers need analytical methods to monitor the presence of allergens during production and to avoid cross-contamination in production lines.

Is there a penalty for non-compliance with FALCPA?

Yes. A company and its management may be subject to civil sanctions, criminal penalties, or both under the Federal Food, Drug, and Cosmetic Act if one of its packaged food products does not comply with the FALCPA labeling requirements. FDA may also request seizure of food products where the label of the product does not conform to FALCPA's requirements. In addition, FDA is likely to request that a food product containing an undeclared allergen be recalled by the manufacturer or distributor.

Contaminants ADI

acceptable daily intake The maximum allowable limits are often well below toxicological tolerance levels

Pesticides and carcinogens food contaminants

banned pesticides

Food Protein Allergens in mmilk

caseins • β lactoglobulin • α lactalbumin Protein

Agrochemicals food contaminants

chemicals in ag practices (pesticides, vet drugs)

Selecting a method

consider cost qualitative result detect one specific allergens Quantative allergens Detect

Biological food contaminants

food poising and food spoilage

Allergic Response:

gastrointestinal (nausea, vomiting, diarrhea) respiratory (nasal, asthma, swelling) skin (hives, edema) systemic (anaphylaxis

Processing food contaminants

generated during processing but absent in raw materials

Physical food contaminants

hair, glass, metal, pests, jewelry, dirt, fingernails

Environmental food contaminants

in the area where food is grown, packaged, processed

Food Allergens

milk, eggs, fish, shellfish, wheat, soy, peanuts, treenuts There are over 160 known sources of food allergen • The big 8 are responsible for 90% of all food allergens • Roughly 2% of adults and 5% of young children in the US have a food allergy • 30,000 consumers visit the emergency room each year

Antibody (immunoglobulin

protein used by immune system to identify and neutralize foreign substances

Anaphylaxis:

serious whole body allergic reaction that can be life threatening

Antigen

substance that triggers the immune system to produce antibodies

Epitope (antigenic site):

the part of the antigen that is recognized by the antibody