Applications of microprobe Raman spectroscopy in food science

The Raman microprobe combines the analytical properties of Raman spectroscopy and the visualization capabilities of a high quality microscope, allowing localization and identification of species and phases in time intervals of seconds to a few minutes with a spatial resolution down to 1 mum. This article describes the basic principles of operation of the Raman microprobe and some applications that are important in food technology: in situ differentiation between sucrose and lactose crystals and of amorphous and crystalline phases in sucrose; detection of semi-crystalline and gelatinized zones in starch granules, and phase transitions in cocoa butter after heating (melting)/cooling (crystallization) cycles. Extensions of these applications cover the entire range of food constituents.