Achieving the food security goal with the rapid global population growth is a big challenge that requires excessive efforts to include more alternative food sources. Representing the major source of the daily human diet, plant-sourced foods recorded an annual development of >7 % (Yang et al., 2023), which needs more progress in the research, production, and preservation technology directions. Therefore, China, the largest population and potato producer, is trying to add potatoes as a staple food (Zhu, Fang, Wang, Li, & Wang, 2021). Maintaining a food material as a staple food needs to be available around the year while the crop production is seasonal. Therefore, proposing processing and preservation chains for this purpose is mandatory.

Potatoes (Solanum tuberosum L.) are ranked the fourth most important crop and the first crucial non-cereal crop. Potatoes are a significant source of carbohydrates, the major energy source for the daily human diet. Besides, it is a multi-nutritional component source of vitamins B1, B3, and C, minerals (iron, potassium, phosphorus, calcium, and magnesium), as well as crucial phenols and antioxidants (Buzera, Gikundi, Orina, & Sila, 2022; Mowafy & Liu, 2024; Saini, Kaur, Aggarwal, & Dhiman, 2023). Moreover, potatoes' resistant starch can promote health by potentially exerting hypoglycemic and prebiotic effects, guarding against colon cancer, and impeding fat buildup (Bao, Zhou, Yu, & Wang, 2021). Potatoes can be consumed fresh or processed. Refrigerated stores play the leading role in preserving fresh-use potatoes, while they have a high footprint, storage and transportation hazards, critical environmental condition management, and rising costs (Buzera et al., 2022; Kaul, Kaur, Kaur, Mehta, & Kennedy, 2023). On the other hand, drying can provide a practical alternative by reducing the product's moisture activity, decreasing the risks of deterioration, and increasing the product's storage stability (Karacabey, Bardakçı, & Baltacıoğlu, 2023). Drying also has lower costs due to the reduced material volume and the less stringent environmental requirements during storage and transportation (Bai et al., 2022). Besides, drying can present potatoes in ready-to-cook form (slices, cubes, and bars) and flour for several potato-based products (noodles, bread, pasta, etc.) (Buzera et al., 2022; Liu, Mu, Sun, Zhang, & Chen, 2016; Ma et al., 2024).

Hot air drying (HAD) is widely used for dehydrating agricultural products due to its simple design, cost-effectiveness, and ease of control (Karacabey et al., 2023). Despite its popularity, HAD is often associated with drawbacks such as reduced product quality and lengthy processing times (Bai et al., 2022; Wang et al., 2021a). To address these limitations, various enhancements and alternative approaches have been suggested, including humidity-controlled HAD (HC-HAD), infrared-assisted HAD (IR-HAD), and impinged HAD (Wang, Fang, et al., 2021a). Among them, HC-HAD demonstrated the shortest drying time while preserving the physicochemical properties of potato cubes and improving the quality of yam slices (Ju et al., 2016), American ginseng roots (Ju et al., 2020), Amomi fructus (Ai et al., 2023), mushrooms (Li et al., 2022; Liu et al., 2021a). Additionally, HC-HAD proved to be more energy-efficient according to studies by Ju et al. (2018) and Liu et al. (2021b). The HC-HAD considers a high relative humidity (RH) level in the process beginning, which governs the material temperature, moisture diffusion, and equilibrium moisture content, controlling the dried material polymerization and phytochemicals' oxidation (Ju et al., 2020; Sarpong et al., 2019). The higher RH also uniforms the moisture and temperature distribution within the dried material, prohibiting surface hardening and shrinkage (Ju et al., 2020; Liu, Wei, et al., 2021b), while the low RH environment (in HAD) for a long time forms a crust layer on the material surface, weakening the moisture diffusion and the drying rate in the subsequent stage (Li et al., 2022).

Pulsed vacuum drying (PVD) emerges as a promising drying technology offering accelerated drying processes, color retention, and preservation of polysaccharide content in wolfberries compared to the traditional HAD method (Xie et al., 2018). Geng et al. (2023) observed superior retention of properties in sea buckthorn berries despite extended drying times when compared to HAD, IRD, and IR-HAD. An additional study by Deng et al. (2018) demonstrated that PVD yielded improved physicochemical properties in red peppers compared to both HAD and IR-HAD at equivalent drying temperatures. Furthermore, PVD showed benefits in dehydrating kiwifruit slices and rhizoma dioscoreae slices (Liu et al., 2021c; Xie, Gao, Liu, & Xiao, 2017). In PVD processes, materials are subjected to varying pressures (atmospheric and vacuum), where rapid heating under atmospheric pressure facilitates subsequent moisture evaporation under vacuum conditions, potentially enhancing moisture distribution and diffusion dynamics (Liu, Zielinska, et al., 2021c; Xie et al., 2017; Xie et al., 2018).

Prior to processing, potatoes undergo various pretreatments primarily aimed at inactivating browning enzymes and modifying starches (Saini et al., 2023). These pretreatments also play a crucial role in mitigating the adverse effects of drying on product attributes such as shape, color, flavor, and nutritional quality while eliminating harmful compounds like glycoalkaloids (Bai et al., 2022; Rytel, Tajner-Czopek, Aniołowska, & Hamouz, 2013). These pretreatment methods encompass chemical, physical, and biological approaches. Among these methods, blanching stands out as a key hydrothermal treatment essential in potato processing before drying, frying, freezing, or storage (Saini et al., 2023). Blanching is valued for its practicality, simplicity, cost-effectiveness, and lack of chemical residues (Chen et al., 2017; Liu et al., 2019a). Common techniques like hot water blanching (HWB) and stream blanching (SB) are widely used but face challenges such as water wastage, environmental concerns, reduced efficiency, nutrient loss through hydrolysis, and thermal limitations (Mowafy & Liu, 2024; Wang et al., 2023a; Wang, Fang, et al., 2021a). To address these conventional blanching drawbacks, numerous novel blanching technologies were investigated, such as high-humid hot-air impinged (HHAIB), vacuum-steam pulsed (VSPB), microwave, infrared, ultrasonic-assisted, and ohmic heating blanching (Deng et al., 2019; Karacabey et al., 2023; Okonkwo et al., 2022; Wang et al., 2022; Wang, Fang, et al., 2021a). Our previous research revealed the excellence of HHAID and VSPB in blanching potatoes, conserving their physicochemical attributes superior to HWB and SB (Mowafy & Liu, 2024). Also, those two innovative blanching techniques do not adopt complicated technologies and high energy-consuming sources, and they are away from hazardous radiation emissions. Besides, they proved superior in pretreating various foodstuffs, viz. carrots, ginger, apricots, etc. (Deng et al., 2019; Wang et al., 2022; Wang, Fang, et al., 2021a).

Some studies have examined the impacts of hydrothermal and dehydration processes on isolated potato starch properties (Kaul et al., 2023; Liu, Hao, Chen, & Gao, 2019b; Xu et al., 2021). Others have focused solely on the hydrothermal effects on potatoes (Moens, De Laet, Van Ceunebroeck, Van Loey, & Hendrickx, 2021; Mowafy & Liu, 2024; Okonkwo et al., 2022; Wang et al., 2021b; Zhang, Tian, Liu, & Xue, 2020a), while some have explored the drying effect alone (Leeratanarak, Devahastin, & Chiewchan, 2006; Wang, Liu, et al., 2021b; Zhu et al., 2021). However, there is a need for more literature addressing the combined hydrothermal-drying impact on potato products, encompassing both slices and flour, particularly under innovative blanching and drying technologies. Therefore, our research aimed to investigate the synergistic effects of innovative blanching techniques (HHAIB and VSPB) and drying methods (PVD and HC-HAD) in comparison to traditional approaches (HWB, SB, and HAD). Our objective was to assess the drying kinetics and physicochemical properties of dried potato slices, as well as the functional properties of produced potato flour influenced by various blanching and drying methods. This study seeks to provide valuable insights that can enhance potato researchers' and producers' understanding and practices, ultimately adding significant value to the field.