Detection of CNS Tissue in Meat Products

Many methods have been investigated and are in use today for detection of CNS tissue in meat products, but not necessarily for all SRMs. In order to identify which test is the most efficacious, the factors of subjectivity versus objectivity, labor, the need for quantitative versus qualitative results, cost, training of qualified personnel, sensitivity, and specificity must be considered. In addition, effects of processing (including grinding, heating, and the addition of other ingredients that may interfere with the assay) must be 

They found it to be a useful marker for CNS tissue and, more specifically, a useful marker for differentiating between CNS tissue and tissues of the peripheral nervous system in AMR products (Kelley et al., 2000). 

There are many immunochemical methods that have been implemented 

CNS tissue presence in meat products. Immunochemical methods offer 

Lucker et al. (2001) evaluated 126 liver sausages for presence of CNS tissue using an immunoassay that detects presence of NSE. They detected CNS tissue in 5 of 126 samples assayed using NSE immunochemistry, and concluded that NSE immunochemistry was a highly specific and moderately sensitive method for detection of CNS tissue in non-heat-treated meat products (Lucker et al., 2001). 

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As would be expected, most effort has been most focused on the detection of nonmuscle tissue that is related to the enforcement of human health and food safety. To enable effective enforcement and removal of SRM, there has been a need for the development of robust CNS (central nervous system)-specific detection methods that are applicable to a wide range of processed meat products. In the case of non-DNA-based techniques, methods for the detection of CNS tissue in meat include direct tissue examination (Bauer et al., 1996), histological preparation and microscopic examination (USDA-FSIS, 1998), and the analysis of cholesterol content (LiickeretaL, 1999 Schmidt et al., 1999). 

Lucker et al. (2004) evaluated the ability of GC-MS using several brain-specific fatty acids to identify and quantify CNS tissue in meat products. The researchers determined specific fatty acid content of brains from cattle, calves, sheep, pigs, turkeys, as well as muscle and adipose tissue. They determined that species and age characterizations could be made based on the concentration of specific fatty acids present in a sample. Sensitivity of GC-MS CNS tissue detection was reported to be 0.01% raw weight, but the practical sensitivity was 0.1-0.5% raw weight CNS due to the fatty acid baseline content in muscle and adipose tissue. 

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