ABSTRACT
One very important topic that is not addressed here at all is sample preparation. The range of techniques that are used is so broad for the various types of natural and prepared food materials that covering it would require many volumes and the expertise of many experienced researchers. In some cases nothing more than scattering particles on a contrasting substrate, or using a razor blade to cut a section is required. In other situations, rapid freezing followed by fracturing and coating is needed. Chemical fixatives and stains are widely used. Techniques for electron microscopy differ from those for light microscopy, and so forth. The current literature is generally the best source for reviews of existing techniques and reports of new ones. The goal is to preserve the fine details of structure without alteration or deterioration, with sufficient contrast to show that structure with the chosen imaging technology. The appropriate methods are generally the same for digital image processing as for conventional photographic recording.
