Microstructural analysis of frying potatoes

Frying induces major structural changes in the surface of foods influencing oil uptake. This work discusses the use of several different methods of mi croscopy as well as techniques of image analysis to study frying at the mic rostructural level. Hot-stage video microscopy was instrumental in assessin g geometrical changes in cells of potato tissue and in starch in real time. The swelling of starches inside cells appeared to be retarded compared wit h that in starch suspensions. Confocal laser scanning microscopy (CLSM) per mitted 'optical' sectioning of the crust, revealing that oil was located in the interior in pockets or surrounding intact cells. The manipulation of m icroscopy data by image processing is also presented.