Researchers at the University of Texas in Austin have reported in a study published in the Journal of Agricultural and Food Chemistry that a handheld device can be used to identify common types of meat and fish within 15 seconds, which could assist in detection of food fraud.
Although current molecular techniques, such as polymerase chain reaction (PCR), are highly accurate, these analyses can take hours to days, and are often performed at off-site labs. Previous studies have devised more direct and on-site food analysis methods with mass spectrometry, using the amounts of molecular components to verify meat sources, but they also destroyed samples during the process or required sample preparation steps. The new device, called the MasSpec Pen, extracts compounds from a material’s surface within seconds and then analyzes them on a mass spectrometer. The investigators wanted to determine whether this device could rapidly and effectively detect meat and fish fraud in pure filets and ground products.
The researchers used the pen to examine the molecular composition of grain-fed and grass-fed beef, chicken, pork, lamb, venison, and five common fish species collected from grocery stores. Once the device’s tip was pressed against a sample, a 20-μL droplet of solvent was released, extracting sufficient amounts of molecules within three seconds for analysis by mass spectrometry.
The researchers report that the process took 15 seconds, required no preprocessing, and the liquid extraction did not harm the samples’ surfaces. The team developed authentication models using the unique patterns of the molecules identified, including carnosine, anserine, succinic acid, xanthine, and taurine, to distinguish pure meat types from each other. They then applied their models to the analysis of test sets of meats and fish. For these samples, all models had a 100% accuracy identifying the protein source, which is as good as the current method of PCR.
The researchers say they plan to expand the method to other meat products and integrate the device into a portable mass spectrometer for on-site meat authentication.