Review: Confocal scanning laser microscopy. A powerful tool in food science

Confocal scanning laser microscopy (CSLM) is a recently developed light mic roscopy technique which permits observation of selected levels within thick samples. CSLM improves the resolution along the viewing axis and permits o ptical sectioning of the sample. Sample preparation is not time consuming a nd changes the original structure of the specimen only minimally. In this w ay structures involved in kinetic processes of food materials exposed to ex ternal stress situations can be visualized. In this review the contribution s of CSLM to improving the understanding of various processes in different fields of food science are discussed. The fundamentals of the operations re quired are considered, including a discussion of common laser sources and d ifferent kinds of fluorescent dyes. Attention is paid to the peculiarities of sample preparation, as well as to the possibilities of image processing in order to improve and analyze the images collected. The quantitative anal ysis of plant organizations and cellular structures in plant material by CS LM is reported as well as the use of CSLM to image the structure of emulsio ns of different complexity and to locate microorganisms in a wide range of food products.