Today is International Celiac Day; close to one percent of the global population suffers from celiac disease, a complex auto-immune disorder caused by the ingestion of gluten, for which there is no treatment besides eliminating gluten from the diet. As such, the detection of gluten before the product reaches the consumer is essential, in order to guarantee the food safety and prevent possible health problems in people who suffer from celiac disease.
With this objective, a team from the Universitat Politècnica de València (UPV), belonging to the Molecular Recognition and Technological Development (IDM) Institute, has developed a new test for the food industry that uses a cell phone to detect gluten in food in a simple, fast and inexpensive manner. Their research has been published in the journal Food Control.
“Our prototype is designed to help control foods from the moment they are produced, in such a way that when they reach the table, they are one hundred percent safe for the consumer, which in this case, is people who suffer from celiac disease. Its main advantage is how easy it is to use and its response times. Today, specialized staff is required to do this analysis. Among other processes, a sample must be taken to the laboratory, which takes at least five hours to get the result; whereas with our system, we can know whether or not a food has gluten in fewer than two hours,” indicates Luis A. Tortajada Genaro, researcher from the IDM Institute of the Universitat Politècnica de València. María Isabel Lucío and Ángel Maquieira, both of whom work at the IDM Institute, have participated in developing this system along with Luis A. Tortajada Genaro.
The system designed by the UPV team is a color test in which the change of color—in this case, turning red—indicates the presence of gluten in the food. “The process is very simple: we take a food sample, we grind it up, extract the DNA and amplify it. Once the sample has been prepared, we mix it in a vial with gold nanoparticles, and in just 10 minutes, it’s ready to measure and that’s where the cell phone comes into play,” described Tortajada.
Similar to the antigen tests that are so en vogue today, to analyze a food with this method from UPV, you only need three droplets of the sample, which are deposited on a plastic membrane, which you then take a picture of with your cell phone. “Based on the apps available on the market, we can break the color down into three primary colors: red, green and blue—the RGB breakdown. The redder it is, the more gluten concentration there is in that food. Thus, in a fast and simple way, we can detect whether or not there is gluten in the food, and even its concentration level,” Tortajada pointed out.
Preventing fraud in meat products
In addition, for the detection of gluten, the team from the IDM Institute has applied this new test to prevent fraud in the food industry, specifically to detect possible adulterations of meat products.
“During the preparation of certain meat products, to improve its properties, grains are added, even though the regulations establish a limit. In our case, we apply the test to detect a specific gene from these grains, with the objective of controlling it to not exceed that maximum quantity,” explained Luis A. Tortajada.
For the UPV researcher, the results obtained in their laboratories in both cases “show that the biodetection system developed is very competitive, and it allows for better product control. It is a system that responds to the demands of the food industry and consumers and contributes to guarantee food quality at all times, following the ‘from farm to fork’ strategy,” concluded Tortajada.
Research: Fast DNA biosensing based on isothermal amplification, unmodified gold nanoparticles, and smartphone detection