Abstract
Potato tubers are often considered by food processors as being “homogenous” plant structures. However, tubers are complex organs made up of many tissue types, including a complex vascular system, each with different functions and properties that can affect the influence of pulsed electric fields (PEF) on cell and tissue structures. Many research investigations evaluating the effects of PEF on the microstructure of potato tuber have used samples that have been mechanically fragmented prior to PEF treatment and unfortunately the internal structure of vascular system inside the tuber has been ignored during sample preparation, PEF treatment, and microstructure analysis. This chapter discusses different methodologies that have been used to assess the effect of PEF treatment on potato tubers, including electrical impedance and conductivity measurements, cell viability staining, enzymatic browning, and microscopic techniques such as light microscopy, fluorescence microscopy, scanning electron microscopy, energy dispersive spectroscopy, and also magnetic resonance imaging. The limitations of each technique and how these techniques have been used in published studies are discussed. In addition, this chapter demonstrates how sample pretreatments such as peeling or cutting influence the assessment of PEF effect on the microstructure of the tuber and how several techniques should be used and combined in order to understand how the PEF effects are distributed throughout the whole potato tubers.