ELISA to Quantify Triose Phosphate Isomerase to Potentially Determine Processing Adequacy in Ground Beef

Triose phosphate isomerase (TPI) was purified from bovine semimembranosus muscle using acetone precipitation, ammonium sulfate precipitation and cation exchange chormatography. Anti-TPI polyclonal antibodies (PAbs) were raised in rabbits. A sandwich ELISA with a limit of detection of 1 μg TPI/mL was developed using PAbs for capture and biotinylated PAbs for detection. Cross-reactivities of antibodies with other protein in beef muscle extracts and with TPI from different animal species were examined. TPI concentration and activity of ground beef decreased (P < 0.0001) as cooking temperature was increased from 48.9 to 76.7°C, suggesting that these assays might be used to monitor processing adequacy of beef products.