The beverage industry has a strong economic interest in the online monitoring of various process parameters such as the concentration of dissolved carbon dioxide, or the alcohol and sugar levels. Until today, it is common practice to determine the parameters off-line in the company's laboratory. In order to meet the increasing requirements for process safety, quality control and economic efficiency, online monitoring is more and more requested
ATR infrared spectrometer measures CO2 in liquids
In cooperation with the company Centec GmbH, Fraunhofer IPM has developed an optical sensor for the determination of carbon dioxide in beverage processes. The sensor is based on the infrared optical measuring technique called attenuated total reflection (ATR) spectroscopy. Following process-specific adaptations, Centec is now offering the sensor as a product.
Nanocrystalline diamond layers for ATR measurements in the MIR
Compared to conventional measuring techniques in the near-infrared, sensing in the mid-infrared is much more sensitive and selective, e.g. when determining the concentrations of alcohols and sugars. However, MIR measurement techniques usually fail due to the lack of process suitability of most infrared materials. Those typically lack sufficient chemical resistance regarding the process media (acidic or alkaline stability). The collaborative project MiDioS (Microstructured diamond for optical systems - scalable basic technology and deployment in ATR infrared spectroscopy) aims to make MIR sensor technology suitable for process use. In cooperation with industrial partners, Fraunhofer IPM is providing the scientific and technical basics for this: We are focusing on novel nanocrystalline diamond layers for ATR metrology. The optical and chemical properties of diamond clearly exceed the properties of all known materials, especially in the mid infrared range.
Part of this work was funded within the German funding program »Zentrales Innovationsprogramm Mittelstand - ZIM« (KF3254505AB4) an within the BMBF call »Photonik nach Maß – Funktionalisierte Materialien und Komponenten für optische Systeme der nächsten Generation« (13N14577).