Food allergen testing plays a crucial role in ensuring the safety and well-being of individuals with food allergies. Allergens are proteins present in certain foods that can trigger adverse reactions in susceptible individuals, ranging from mild symptoms to life-threatening anaphylaxis. Accurate allergen detection is essential to prevent allergen cross-contamination, mislabeling, and unintended exposure in food products. In recent years, several methods have been developed to accurately detect and quantify allergens in food products and food-processing facilities. The most widely used technologies in this field are Enzyme-linked Immunosorbent Assay (ELISA), Polymerase Chain Reaction (PCR), and Lateral Flow Assays (LFA). Each of these methods offers distinct advantages and applications in food allergen detection. Collectively, they enable the food industry to effectively detect and quantify allergens, thereby mitigating risks and upholding food safety standards. This blog post explores the differences and applications of these technologies in food allergen detection to emphasize their significance in safeguarding public health and promoting consumer trust in the food supply chain.
ELISA is a widely used and established technology for food allergen detection. It is based on the principle of antigen-antibody interaction, using antibodies that specifically bind to allergenic proteins present in food samples. The process begins with the preparation of food samples, which usually involves a procedure to extract proteins. These extracts are then added to wells of a microplate that have been coated with antibodies specific to the allergen of interest. If the allergenic protein is present, it binds to these antibodies. A secondary antibody, linked to an enzyme, is then added, binding to the allergen-antibody complex. When a substrate of that enzyme is added, it reacts to produce a measurable signal, typically a color change. The intensity of this signal, measured using a spectrophotometer, correlates with the amount of allergen present, allowing for precise quantification. ELISA’s high sensitivity and specificity enable it to detect and quantify allergens at very low concentrations, which is crucial for food testing laboratories. The method is versatile, capable of testing a wide range of food products, from raw ingredients to processed foods.
PCR is a molecular biology technique that amplifies specific DNA sequences, making it a powerful tool in food allergen detection. By targeting DNA sequences unique to allergenic proteins or species, PCR can accurately identify the presence of allergens, even in processed or heavily treated food products. The process begins with the extraction of DNA from food samples. This DNA is then mixed with primers, which are short nucleotides that hybridize specifically with the target allergen’s DNA. The mixture is placed in a thermal cycler, which repeatedly heats and cools the sample to promote the synthesis of new DNA strands. This cycle of heating and cooling is repeated multiple times, exponentially amplifying the target DNA sequence. The amplified DNA is then detected by real-time PCR, which provides a measurable signal indicating the presence of the allergen. PCR is recognized by its multiplexing capability and offers a higher throughput than other techniques for allergen testing.
Lateral flow assays (LFAs) are a popular and efficient technology for food allergen detection, known for their simplicity and rapid results. These devices use the principle of immunochromatography, where antibodies are used to detect the presence of allergenic proteins in a variety of sample types. The sample is applied to the sample pad of the lateral flow device which is comes in a strip format. The sample migrates along the test strip by capillary action. As it moves, it encounters a conjugate pad containing antibodies that are specific to the allergen of interest and are labeled with a detectable marker, such as colloidal gold. If the allergenic protein is present, it binds to these labeled antibodies. The sample continues to migrate along the strip to the test line, where another set of antibodies specific to the allergen is immobilized. The allergen-antibody complex binds to these immobilized antibodies, forming a visible line. The intensity of this line indicates the presence and, to some extent, the quantity of the allergen. A control line further along the strip confirms that the test has worked correctly. LFAs are highly valued for their rapid results, often providing answers within minutes. They are user-friendly and do not require specialized equipment or extensive training, making them suitable for on-site testing in various settings, including food manufacturing facilities and retail environments.
Often, using a combination of the different technologies can enhance food allergen testing by providing complementary strengths and overcoming limitations of individual methods. Here are some scenarios where an integrated approach can lead to more reliable results:
Are you in need of advanced solutions for food allergen testing? Look no further! We are proud to offer a comprehensive portfolio of all the above-mentioned technologies through our InviScreen®, InviRapid® and InviLisa® product lines.
Our integrated approach to allergen testing enables you to enhance the safety and quality of the food industry by leveraging the combined strengths of these cutting-edge technologies. The infographic below identifies critical points and areas throughout the entire food process - from receiving raw materials to production, labeling, and processing - where allergen risks may occur. It also details the most effective methods for allergen detection.
Invitek Diagnostics provides a variety of tests capable of detecting target allergens in ingredients, clean-in-place rinses, finished products, and on environmental surfaces. Visit our website to explore our complete portfolio and take a step towards elevating your food safety standards today!
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