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 erro rs in both the enzymatic calibration and determination of cell dry wei ght methods. The results were better in the case of slurry samples pre sumably because the error in the drying method was removed. Direct slu rry measurement is also more rapid and more desirable for future inlin e applications. Further improvements in the measurement of yeast glyco gen by NIR as previously published are also reported. NIR reflectance would appear to be a promising technique for the rapid in-line measure ment of yeast intracellular components within a brewery.