Development and Validation of a Rapid Qualitative Test Kit for Detection of Raw and Cooked Pork Meat and Gelatin Residues

Introduction: Reports over the past years show that pork adulteration, accidental or intentional, in beef retail products is relatively common. To broaden the application of rapid testing for meat authentication, we developed two Lateral Flow Devices (LFDs) to detect raw and cooked pork, as well as pork gelatin, in beef.

Purpose: To develop a highly specific detection kit that can rapidly detect raw and cooked pork meat and gelatin residues in beef.

Methods: Goat antibodies against porcine serum albumin (PSA) and thermal stable meat protein (TSMP) were used to prepare a lateral flow immunochromatographic assay (LFIAs or LFDs). Sample extraction buffers and running buffers were developed to enable detection of raw porcine meat, cooked meat, and gelatin from beef samples. These kits and test methods were validated for sensitivity, specificity and dynamic range. Method concordance was assessed using a PCR-based meat authentication method (IEH).

Results: The Pi Bioscientific pork meat LFD has a limit of detection (LOD) of 0.01% spiked raw pork meat (into beef meat), 1% spiked cooked pork meat (into cooked beef meat), and 0.1-2.5% spiked gelatin (depending on whether it was buffer or candy gelatin). Specificity analysis revealed no cross-reactivity with meats derived from chicken, turkey, horse, beef, lamb, and goat. The assay was able to detect gelatin residues where PCR methods failed due to the inability to recover DNA from gelatin.

Significance: The development of a highly specific test system to detect trace amounts of both raw and cooked pork meat as well as gelatin in ~40 min can become an important tool for food safety authorities, contract laboratories and food producers in their continued efforts to monitor the purity of meat products.