NYT: A Meat test

A Simple Test to Detect Nervous Tissue in Beef
By HENRY FOUNTAIN
To protect people against the human variant of mad cow disease, health experts say, it is crucial to keep central nervous system tissue of beef cattle out of the food supply. And that means controls and testing at slaughterhouses, where there is a risk that tissues will become mingled when animals are killed and processed.

Testing for the presence of central nervous system tissue has been a tedious affair, involving chromatography, polymerase chain reaction assays or other laboratory techniques. What has been needed is a simple test that can be performed on cattle carcasses or meat products rapidly and in real time.

That test may be close to reality. Scientists with the Department of Agriculture and Iowa State University report in The Journal of Agricultural and Food Chemistry that they have detected nervous system tissue on cattle carcasses with a fluorescence-based method.

The technique devised by Jacob W. Petrich and colleagues takes advantage of the fact that nervous system tissues contain high concentrations of a compound, lipofuscin, that fluoresces when exposed to light. By analyzing the fluorescence with a spectrometer, the method can detect even small amounts of nervous system tissue on a carcass.