Issues in development of NIR micro spectrometer system for on-line process monitoring of milk product

The development of a near-infrared (NIR) spectrometer system for on line monitoring of fat in milk processing is outlined. This system uses microsystems optical components fabricated using the LIGA technique. This technique is used in microelectronics to fabricate high definition structures in silicon. For production of large numbers of components significant cost reductions can be realised over conventional methods. To date these LIGA fabricated spectrometers have found applications in colour analysis and in quality analysis in diamonds, but have not been integrated into on-line process applications. This work outlines initial installation and test of such a system in a milk processing environment. The possibility of low cost optical systems being introduced for process control may occur with future work. This technology, operating in the near infra red (800-1100 nm), enables a number of applications to be investigated. The system hardware is outlined and initial tests with the first field installation are discussed. The system has been shown to be sensitive to required changes in fat content.