DAIRY PRODUCT ANALYSIS - IDENTIFICATION OF MICROORGANISMS BY MIDINFRARED SPECTROSCOPY AND DETERMINATION OF CONSTITUENTS BY RAMAN-SPECTROSCOPY

Identification of microorganisms by traditional microbiological method s is time consuming. The German Federal Health Office has developed a method using mid-infrared spectroscopy to identify microorganisms rapi dly. This method has been modified for application to microorganisms i mportant in the dairy industry. Mid- and near-infrared spectroscopies are well-established methods for quantitative measurements of fat, pro tein, lactose, and solid content in a variety of products. A disadvant age of both methods is the huge absorption due to water; extraction of other components is complicated and can be achieved only statisticall y. With Raman spectroscopy, water causes less absorption. We investiga ted the use of Raman spectroscopy as a quantitative method for milk po wder.