RAPID YEAST TREHALOSE MEASUREMENT USING NEAR-INFRARED REFLECTANCE SPECTROMETRY

The rapid measurement of yeast trehalose by Near Infra-Red Reflectance (NIR) spectrometry is demonstrated for both dried and slurry samples. The reproducibility of the method was acceptable considering the errors in both the enzymatic calibration and determination of cell dry weight methods. The results were better in the case of slurry samples presumably because the error in the drying method was removed. Direct slurry measurement is also more rapid and more desirable for future inline applications. Further improvements in the measurement of yeast glycogen by NIR as previously published are also reported. NIR reflectance would appear to be a promising technique for the rapid in-line measurement of yeast intracellular components within a brewery.