TY  - GEN
A1  - Engelhard, Sonja
A1  - Kumke, Michael Uwe
A1  - Löhmannsröben, Hans-Gerd
T1  - OPQS – optical process and quality sensing : exemplary applications in the beerbrewing and polyurethane foaming processes
N2  - Optical methods play an important role in process analytical technologies (PAT). Four examples of optical process and quality sensing (OPQS) are presented, which are based on three important experimental techniques: near-infrared absorption, luminescence quenching, and a novel method, photon density wave (PDW) spectroscopy. These are used to evaluate four process and quality parameters related to beer brewing and polyurethane (PU) foaming processes: the ethanol content and the oxygen (O2) content in beer, the biomass in a bioreactor, and the cellular structures of PU foam produced in a pilot production plant.
T3  - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - paper 004 
KW  - process analytical technology
KW  - beer
KW  - biomass
KW  - foam analysis
KW  - NIR spectroscopy
KW  - fluorescence quenching
KW  - photon density wave spectroscopy
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-12191
ER  - 
TY  - JOUR
A1  - Engelhard, Sonja
A1  - Kumke, Michael Uwe
A1  - Löhmannsröben, Hans-Gerd
T1  - Examples of the application of optical process and quality sensing (OPQS) to beer brewing and polyurethane foaming processes
N2  - Optical methods play an important role in process analytical technologies (PAT). Four examples of optical process and quality sensing (OPQS) are presented, which are based on three important experimental techniques: near- infrared absorption, luminescence quenching, and a novel method, photon density wave (PDW) spectroscopy. These are used to evaluate four process and quality parameters related to beer brewing and polyurethane (PU) foaming processes: the ethanol content and the oxygen (O-2) content in beer, the biomass in a bioreactor, and the cellular structures of PU foam produced in a pilot production plant
Y1  - 2006
UR  - http://www.springerlink.com/content/100417
U6  - https://doi.org/10.1007/s00216-005-3364-4
SN  - 1618-2642
ER  - 
TY  - JOUR
A1  - Engelhard, Sonja
A1  - Löhmannsröben, Hans-Gerd
A1  - Schael, Frank
T1  - Quantifying ethanol content of beer using interpretive near-infrared spectroscopy
N2  - On the basis of absorption measurements in the near-infrared (NIR) spectral range, a new method for the quantification of the ethanol content of beer is presented. Instead of the multivariate calibration models most commonly employed in NIR spectroscopic works, we use interpretive difference spectroscopy: Two wavelengths are selected according to the assignment of the absorption bands of the main substances of content of beer in the NIR region, and the difference between the absorbances at these wavelengths is used for ethanol quantification. Absorption spectra of the dominating beer ingredients are discussed and the calibration procedure with ethanol/water mixtures is shown. Robustness against the carbohydrate content of beer samples was demonstrated by analyzing solutions of ethanol and maltose in water. Validation of the method was performed with various beer samples with an ethanol concentration range between 0.5 and 7.7 vol %. The pertinent advantage of the procedure developed in this work is the indication that the results are independent from seasonal variations of the ingredients, which is of high interest for products with natural ingredients such as beer
Y1  - 2004
SN  - 0003-7028
ER  - 
TY  - THES
A1  - Engelhard, Sonja
T1  - Optische Verfahren zur Qualitätskontrolle von Bier und zur Zellzahlbestimung in S. cerevisiae Kultivierungen
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Schael, Frank
A1  - Engelhard, Sonja
A1  - Reich, Oliver
T1  - Optische Sensorik für die in-situ-Analytik von Brauprozessen
Y1  - 2001
ER  -