For millions of individuals living with severe food allergies, dining safely requires trust in food manufacturing. Even an invisible trace of an allergen or an undeclared ingredient transferred across shared factory lines can trigger a potentially life-threatening reaction. To identify these hazards before foods reach grocery shelves, food processors rely on sensitive analytical screening methods. Now, a study published in npj Science of Food introduces a miniaturized DNA extraction cartridge that could make screening for hidden food allergens simpler, less expensive, and less chemically intensive.
Led by Carla Teixeira at the International Iberian Nanotechnology Laboratory in Portugal, alongside researchers from Spain and Germany, the team focused on a challenging first step in genetic testing: isolating usable DNA from complex food samples. Conventional extraction methods often rely on harsh chemicals known as chaotropic salts to help isolate genetic material, adding complexity to laboratory procedures. In contrast, the new prototype employs controlled pore glass inside a compact cartridge to capture and release DNA without relying on these aggressive salts.
Detecting allergen-containing ingredients through DNA rather than proteins offers certain technical advantages in modern food processing. DNA can remain detectable after roasting, baking, and extrusion, even when heat has altered proteins and complicated their identification, although sufficiently intense processing can also degrade genetic material. When paired with quantitative real-time PCR (qPCR), laboratory assays can amplify tiny amounts of target DNA, helping analysts identify specific ingredients such as sesame within complex food mixtures. Importantly, DNA testing identifies genetic evidence of an ingredient rather than directly measuring the allergenic proteins responsible for reactions.
One major hurdle in industrial screening is the complexity of the food itself. Ingredients rich in fats, sugars, and starches can introduce substances that interfere with the enzymes required for PCR testing. While commercial extraction kits can address these challenges, they also involve recurring expenses, multiple processing steps, and specialized laboratory procedures. The researchers sought to simplify this process by developing a compact extraction system suited to food allergen surveillance.
When benchmarked against established commercial extraction kits, the prototype generally produced lower DNA yields, with reported concentrations of approximately 1–4 nanograms per microliter and relatively modest purity measurements. Nevertheless, the extracted DNA supported successful qPCR amplification, demonstrating that obtaining large quantities of highly purified DNA is not always necessary for effective genetic screening. For this application, the ability to recover DNA that can be successfully amplified may be more important than maximizing extraction yield alone.
To demonstrate its practical potential, the researchers evaluated the device using three food safety scenarios: raw seeds, commercial bakery mixes, and contaminated stainless-steel surfaces. The cartridge successfully supported the detection of sesame DNA in complex baking mixes containing ingredients that can interfere with conventional testing. In surface experiments, researchers also detected sesame residues applied to stainless-steel test coupons at a contamination level of 2.5 micrograms per square centimeter. These findings suggest the technology could eventually help manufacturers verify cleaning procedures and monitor equipment for allergen cross-contact, although additional testing is needed to establish its sensitivity and reliability under routine factory conditions.
Supported in part by the European Union’s TITAN project, the cartridge’s compact design and reduced reliance on harsh extraction chemicals make it a promising candidate for integration into automated testing platforms. As food manufacturers face increasing demands to identify undeclared allergens and prevent cross-contact, technologies that simplify DNA preparation could make routine screening more accessible. Although further validation, automation, and cost comparisons are needed before widespread industrial adoption, the research offers a promising step toward more efficient detection of hidden allergen-containing ingredients in food production.
