In recent years there have been a number of serious scandals relating to meat safety and quality and on July 1st 2008 new regulations from the European Commission came into force with the aim of improving product traceability, as well as identifying and evaluating slaughter offal and meat not designated for human consumption. As has been previously reported fluorescence spectroscopic signals from pork meat can be used as indicators of meat freshness [1,2]. Furthermore, the signals can be measured rapidly through polyethylene packaging and without the destruction of the meat sample allowing non-invasive testing. This provides a pathway to meat quality monitoring. In this study, we have developed a hardware concept for measuring fluorescence signals using a compact and light handheld device with the aim of providing a miniaturised solution for the monitoring of meat quality through these signals. The handheld device comprises an optical transduction unit or optode which delivers excitation light to the sample and sub sequentially carries the light back to the detection unit. We have used a fibre optic approach for this which allows for very compact sensor fabrication based on the small size of the optical fibres, and commercially available components have been used in the device-manufacture leading to a low-cost solution. The optical design of the sensor head is based on an analytical model and numerical simulations to maximise signal intensity. To integrate the instrumentation into a compact and portable scanner, we have developed a design in which the light sources, optodes, detectors and electronic circuits have been integrated into a compact volume using a microsystems approach and a system concept with low energy consumption. We introduce our optical system design in section 3 followed by the electronic subsystem in section 4. In section 5, a set of characterisation experiments have been carried out using standard fluorescent chromophores such as fluorescein 27 which has an emission spectrum in the same spectral region as that of meat. These tests have been used to characterise the device sensitivity and reliability of operation. Section 6 concludes our work and gives an outlook.
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