Quantitative Evaluation of Pork Adulteration in Raw Ground Beef by Radial Immunodiffusion and Enzyme-Linked Immunosorbent Assay

Abstract

Quantitative estimates are important to establish whether pork adulteration in ground beef is accidental or intentional. A standard agar gel radial immunodiffusion (RID) test using forensic-grade antiserum to porcine albumin and an enzyme-linked immunosorbent assay (ELISA) using forensic-grade anti-porcine glycoprotein immunoglobulin were used to determine from 1 to 75% raw pork in raw ground beef. The RID test, which incorporated 1.5% anti-pork serum in 1% immunodiffusion agar, formed precipitin rings with pork albumin in agar wells. A linear standard curve was obtained by plotting the diffusion area against standard pork concentrations ranging from 0 to 80%. For the ELISA the endpoint optical density increased linearly versus log % pork between 0.0625% and 2% pork. In spiked samples, the RID test had a detection limit of 3 to 5%, a coefficient of variation (CV) of 22%, and a recovery of 105%. The ELISA had a detection limit of 1%, a CV of 18%, and a recovery of 114%. The mean recovery from the spiked samples by the ELISA and RID test was not significantly different (P > 0.05) from the known sample amounts. Quantitation by RID of 28 ground beef samples (27 of which were DTEK ELISA-positive for pork adulteration) revealed a wide range of pork content, with values as high as 48%.

Adulteration detection technologies used for halal/kosher food products: an overview

“…The detection limit and coefficient of variation (CV) of the test were 1% and 18%, respectively. They successfully performed a quantitative evaluation of pork adulteration in raw ground beef using ELISA [ 118 ]. Mandli et al used rapid ELISA and immunosorbent assays using HRP conjugated polyclonal anti-pig IgG antibody to detect low levels ( 0.01%) of pork adulterants in beef [ 119 ].…”

Determination of food authenticity by enzyme-linked immunosorbent assay (ELISA)

“…Also, quantitative methods have been shown. For example, Martin, Chan, and Chiu (1998) carried out successfully a quantitative evaluation of pork adulteration in raw ground beef by ELISA. Furthermore, Chen and Hsieh (2000) and Liu et al (2006) developed MAbs against porcine thermalstable muscle protein and quantified pork meat in raw and heat-processed meat and feed products by this technique.…”

Detection of roe deer, red deer, and hare meat in raw materials and processed products available in Poland

“…In the United States, the use of standard agar gel radial immunodiffusion test and an enzyme-linked immunosorbent assay (ElISa) has indicated minced beef adulteration. In 27 of 28 samples of tested products, high pork content was revealed [28]. In contrast, samples of beef, chicken, and pork hamburgers on the Brazilian market tested by using dot-ElISa, showed no adulteration with beef, chicken, swine, or horse meats [26].…”