Non-destructive mobile monitoring of microbial contaminations on meat surfaces using porphyrin fluorescence intensities.

A non-destructive mobile system for meat quality monitoring was developed and investigated for the possible application along the whole production chain of fresh meat. Pork and lamb meat was stored at 5°C for up to 20days post mortem and measured with a fluorescence spectrometer. Additionally, the bacterial influence on the fluorescence signals was evaluated by different experimental procedures. Fluorescence of NADH and different porphyrins could be correlated to the growth of diverse bacteria and hence used for contamination monitoring. The increase of porphyrin fluorescence started after 9days p.m. for pork and after 2days p.m. for lamb meat. Based on the results, a mobile fluorescence system was built and compared with the laboratory system. The corrected function of the meat slices showed a root mean square error of 1156.97 r.u. and a mean absolute percentage error of 12.59%; for lamb the values were 470.81 r.u. and 15.55%, respectively. A mobile and non-invasive measurement system would improve the microbial security of fresh meat.