Visualization of Food Structure by Confocal Laser Scanning Microscopy (CLSM)

Confocal Laser Scanning Microscopy is a rather new technique for structural analysis of biological and food material. In contrast to conventional light microscopy the light source is replaced by laser, a scanning unit and a pinhole in the back focal plane, which improves the limited depth of focus. The potential and limitations of CLSM are discussed based on experimental work. Yam parenchyma and wheat products (wheat dough, bread and pasta) were imaged by CLSM using Acid Fuchsin and Safranin O as fluorescent dyes. CLSM proved to be a useful tool for obtaining three-dimensional information on the cellular structure of yam parenchyma and on the properties of protein and starch networks in wheat products. Furthermore, CLSM allows the study of bread after baking in situ and the analysis of surface properties of pasta in the reflection mode.