# Processing Fresh-Cut Potatoes Using Non-Thermal Technologies and Edible Coatings
## 5 Emerging Processing Technologies: Operating Principles and Examined Parameters
### Pulsed Electric Field (PEF)
PEF can selectively modulate enzyme activity, providing opportunities to control certain enzymatic reactions that contribute to quality changes in food [149]. This allows for tailored processing that maintains the desired characteristics in the final product. Furthermore, PEF can facilitate the extraction of valuable compounds from raw materials, such as juices from fruits, by disrupting cell structures and enhancing mass transfer [150]. In an industrial setting, PEF can be used to enhance the texture and quality of fresh-cut potatoes, especially for frying applications, as it helps reduce oil uptake and improves crispness. Additionally, PEF can aid in shelf life extension by controlling microbial levels. However, along with its advantages, PEF technology also presents some challenges and disadvantages. The scalability of PEF systems for large-scale food processing remains a technical challenge, and the development of cost-effective and efficient equipment is crucial for widespread adoption [144]. Moreover, the impact of PEF on the overall sensory attributes of food products is still an area of research and development [151]. The potential alterations in texture, color, and flavor need to be thoroughly understood and controlled to meet consumer expectations. Furthermore, the capital investment required for implementing PEF systems in existing food processing facilities can be substantial, posing a barrier to adoption for some companies [144]. PEF technology achieves a rupture of the cell membranes and forms pores (electroporation) in the cellular structure of plant tissues without compromising the quality of the food. Generally, PEF causes a smoother, softer texture and a lower cutting-breaking force of plant tissues. The temperature of PEF-treated potatoes increases by less than 1 \({}^{\circ}\)C [152]. Therefore, cell membrane electroporation, which increases cell membrane permeability, is the main mechanism of PEF processing. The application of PEF (\(E=1.5\) kV/cm and 20 pulses) to potato slices induced pore formation in the cell membrane, altering diffusion characteristics and leading to an enhanced release of intracellular molecules and an improved uptake of low-molecular substances [8]. The application of PEF in the development of healthier fried potato products with a lower fat content has been investigated [3]. In this context, the treatment of potato slices with PEF at a strength of 5 kV/cm reduced the oil absorption of fried potato chips by up to 20.6% due to changes in the cellular microstructure and porosity [3]. However, higher electric field strengths (5-20 kV/cm) had an adverse effect, increasing the average pore diameter and total pore volume. Another work investigated the effect of PEF treatment followed by air drying at 60 \({}^{\circ}\)C on the mechanical properties (maximum cutting force) of fresh-cut potato cylinders [153]. The maximum cutting force, as an expression of fresh-cut potato firming (hardness), was found to increase after PEF treatment at 1 and 1.5 kV/cm [153]. A different study found that the starch properties (thermal stability, gelatinization behavior, susceptibility to digestive enzymes) inside shredded potatoes were not altered after PEF processing [147]. Potato chips prepared by PEF-treated slices were found to contain less acrylamide (approximately 10 ng/g fresh weight) [154]. PEF treatment of steam-pealed tubers can also affect the texture and kinetics of in vitro starch digestibility of French fries [103]. Specifically, the outer crust of PEF-treated fries was significantly harder compared to the crust of fries made from untreated tubers [103]. Other researchers applied PEF prior to vacuum drying (VD) at a fixed pressure of 30 kPa in order to notably reduce the drying time of potato disks [146]. In Table 5, the parameters of PEF applied to fresh-cut potatoes are presented. PEF has also been tested as a pretreatment for potato freeze-drying [142].