Spectroscopic and chemical fingerprints in malted barley

Abstract

A unique "Matrix" of malted barley samples was produced to validate spectroscopic procedures for monitoring the malting process. Three critical factors that were examined in controlling the rate of germination were moisture content, temperature and germination time. Of interest to the malting industry, the analysis indicates the potential to identify new germplasm that, under optimized malting conditions, would produce suitably modified malt in three days of germination. It is also clear that the control of both moisture and temperature is essential for undertaking malting studies. The study suggests that Raman and FTIR could usefully complement NIR spectroscopy for monitoring grain during the malting process. For whole grain NIR measurements, the differences between test grain and control grain at optimal wavelengths of 1280 nm and 2224 nm were found to be valuable parameters for tracking progress during the malting process. The study showed the whole grain NIR most likely assessed changing properties of the periphery of the grain. This research suggested that specific calibration models using NIR for predicting malt quality attributes such as diastatic activity on whole malt are misleading and difficult to interpret because they are highly correlated with other carbohydrate/protein-related attributes of the malt. © 2012 Elsevier Ltd.