# Processing Fresh-Cut Potatoes Using Non-Thermal Technologies and Edible Coatings
## 4 Conventional Processing Technologies and Chemical Treatments
Conventional thermal treatments have drawbacks such as damage in heat-sensitive food compounds like vitamins and polyphenols, high energy consumption, low environmental sustainability, and waste production [95]. Conventional oven-drying usually results in food tissues of a darker color [96]. Conversely, freeze-drying (lyophilization) offers an advantage in terms of retaining the freshness of the product. Chemical treatments and conventional thermal technologies applied to fresh-cut potatoes are summarized in Table 2. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Treatment** & **Processing Conditions** & **Storage Conditions** & **Treatment Purpose** & **Reference** \\ \hline Boiling after immersion & 0.5\% \(\omega/\upsilon\) LA + 0.5\% \(w/\upsilon\) & & & \\ Boiling after immersion & CaCl\({}_{2}\), 10 h immersion, & & & \\ in lactic acid & packed in aluminum foil & - & To improve hardness using & \\ (LA) + CaCl\({}_{2}\) & vacuum pouches & & & \\  & (\(-\)70 kPa), boiling for & & & \\  & 10 min & & & \\ \hline Boiling & 15 min, 95–100 \({}^{\circ}\)C, 200 g & & & \\ slices/1.5 L water, storage & 5–24 h * & & & \\ at 4 \({}^{\circ}\)C & & & & \\  & & & & \\ \hline Blanching (hot water) & 3.5 min at 85 \({}^{\circ}\)C, vacuum-packaged & 12 d, 3 \(\pm\) 1 \({}^{\circ}\)C & & \\  & & & & \\  & & & & \\  & & & & \\ \hline Blanching (hot water) & 95 \({}^{\circ}\)C, 3 min & & & \\  & & & & \\  & & & & \\  & & & & \\  & & & & \\ \hline Blanching (hot water) & 5 min at 65 \({}^{\circ}\)C, & & & \\ potato/water = 1:60 \((\
ice{{w}}/\upsilon)\) & - & & \\ \hline Blanching (hot water) & Pre-cutting treatment at & & & \\  & 55 \({}^{\circ}\)C for 10 min & 6 d, 5 \({}^{\circ}\)C & & \\  & & & & \\ \hline Blanching (hot water) & 30 min at 60 \({}^{\circ}\)C, frying at & & & \\ temperature & 185 \({}^{\circ}\)C for 4.5 min & - & & \\  & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Chemical treatments and conventional thermal technologies applied to fresh-cut potatoes *. In recent years, innovative thermal technologies such as OH, microwave heating, radiofrequency heating, infrared heating, and inductive heating have emerged. These methods aim to generate heat directly within the food material, enhancing energy efficiency in processing [103]. These innovative techniques are discussed in Section 5, with a focus on OH, because they have been recently used under various processing conditions or in conjunction with natural active compounds including plant extracts and essential oils, edible coatings, and non-thermal technologies. Conventional chemical agents employed for fresh-cut potatoes include citric acid, potassium sorbate, chlorine dioxide (ClO\({}_{2}\)), sulfites, ascorbic acid, ethylenediamine-traacetic acid (EDTA), citric acid (C\({}_{6}\)H\({}_{8}\)O\({}_{7}\)), and kojic acid (C\({}_{6}\)H\({}_{6}\)O\({}_{4}\)). These substances serve as anti-browning or firming agents, contributing to the preservation and quality of the potato products. Ascorbic acid, for instance, acts by reducing quinones to phenolic compounds, preventing further reactions that lead to pigment formation [104]. On the other hand, citric acid operates by lowering pH and chelating the copper at the active site of the enzyme [105]. Traditional agents like sulfites are highly effective in preventing both enzymatic and non-enzymatic browning, as they inhibit PPO and other oxidation processes. However, sulfites present health risks, particularly for individuals with sulfite sensitivity or asthma, as they can cause respiratory reactions and allergic responses [106]. Due to these health concerns, regulatory restrictions have been placed on sulfite use in fresh-cut produce, leading to a search for safer alternatives [107]. To mitigate these risks, alternative anti-browning agents, such as plant extracts and essential oils, are being explored for their natural antioxidant properties and lower risk of adverse health effects [108].