## 1 Introduction  
Pectin is one of the most abundant polysaccharides in nature, which is found in the middle lamella of cell wall, primary cell walls, and plasma membrane of plants [1, 2]. It is commercially produced by the industrial waste of apple pomace, citrus peel, and sugar beet pulp [3]. Pectin is mainly composed of linear chains of \(\alpha\)-1,4 linked b-galacturonic acid units but also different types of side chains may exist in its chemical structure such as those containing rhamnose, xylose, galactose, and arabinose [2, 4]. Depending on the side chains, pectin domains are named differently such as homogalacturonan (HGA),hammogalacturonan-I (RG-I), rhamn-1 (RG-II), and xylogalacturonan (XGA) [5; 6]. HGA units are habitually referred as'smooth' regions of pectin and it comprises galacturonic acid groups whereas other units are called 'hairy' regions [4; 7]. Pectin can be used as gelling, thickening, and stabilizing agent in the food and pharmaceutical industry. Moreover, the polyelectrolyte nature, biodegradability, biocompatibility, and water solubility of pectin also open up new uses including coatings or edible films for food packaging applications [8; 9]. Nevertheless, the intrinsically high hydrophilicity and low mechanical strength of pectin-based films compared to conventional ones such as those made of high-density polyethylene (HDPE) and polypropylene (PP) currently limit the application of this carbohydrate [10; 11; 12]. In this context, to enhance the mechanical integrity and also reduce brittleness, plasticizers are habitually added to the pectin formulations to form the films [13]. The addition of different kinds of plasticizers, for instance glycerol [14; 15; 16], sorbitol [13; 17; 18], polyethylene glycol (PEG) [19; 19] or xylitol [20], to polysaccharide film-forming solutions during the casting process can improve both film formation and flexibility by enhancing the motion of polymer chains and reducing their intra- and intermolecular forces [21; 22]. Additionally, water dissolution of pectin can be decreased by in situ cross-linking with divalent metal ions including Ca\({}^{2+}\), Zn\({}^{2+}\) or Mg\({}^{2+}\)[23; 24]. Furthermore, the mechanical, thermal, and barrier properties of the pectin-based films can also be enhanced by blending with other biopolymers such as chitosan [25; 26], cellulose, and its derivatives [27; 28] or the addition of inorganics such as nanoclays [11]. In the polymer literature, neat pectin films are technically not feasible to be produced by conventional melt technologies and they have been so far obtained by the solvent casting method using large contents of plasticizers [24; 25; 29; 30]. In this regard, electrospinningning is a novel technique that provides manufacturing of ultrathin fibers with diameters extending from several nanometers to a few micrometers [31]. Electrospun nanofibers may offer many functional advantages such as superior mechanical properties, large surface-to-mass ratio, tailored fiber morphology, and the capability of encapsulation and subsequent release of active and bioactive principles [32; 33; 34; 35; 36]. However, aqueous solutions of neat pectin cannot be electrospun due to the limited viscoelasticity of pectin and its insufficient chain entanglements [37; 38; 39]. As a result, electrospun pectin nanofibers have been only obtained by blending with different synthetic polymers such as polyethylene oxide (PEO) [39; 40; 41; 42; 43; 44; 45], polyvinyl alcohol (PVOH) [46; 47; 48], and pullulan [38]. In addition, ternary blends of alginate/pectin/PEO [49] and chitosan/pectin/PVOH [50] have been recently successfully electrospun for biomedical purposes. The few studies reporting the development of electrospun pectin-based nanofibers have been mainly focused on the areas of antibacterial surfaces [48], tissue engineering [40; 41; 42; 50], drug delivery [44], and encapsulation [38; 49], whereas their utilization for food packaging applications remains unexplored due to the inherent discontinuity and porous structure of the nanofibers mats.