Evaluation of probe designs to measure connective tissue fluorescence in carcasses.

Three probes were evaluated for their effectiveness in measuring connective tissue fluorescence within carcasses or primal cuts: 1) a quartz-glass rod, 2) a light guide formed from bundles of optical fibers, and 3) a single optical fiber. The shape of the fluorescence emission spectrum of tendon was altered by the method of measurement, probably because of differences in the intensity of excitation. The single optical fiber design provided the best solution to the problem caused by the irregular distribution of connective tissue in meat, and a modified fat-depth probe was tested as a prototype. Beef shank had more fluorescence peaks per millimeter (P less than .01), a greater area above minimum fluorescence (P less than .01), and a greater mean peak intensity (P less than .005) than did psoas major.