Anti-browning and barrier properties of edible coatings prepared with electrospraying Muhammad Kashif Iqbal Khan a,c, ⁎, Hulya Cakmak b , Şebnem Tavman b , Maarten Schutyser a , Karin Schroёn a a Wageningen University, Food Process Engineering Group, Bomenweg 2, 6703 HD Wageningen, The Netherlands b Ege University, Graduate School of Natural and Applied Sciences, Department of Food Engineering, Bornova 35100, Izmir, Turkey c Department of Food Engineering, University of Agriculture, Faisalabad, Pakistan abstract article info Article history: Received 11 June 2013 Accepted 7 October 2013 Available online xxxx Editor Proof Receive Date 8 November 2013 Keywords: Electrospraying Browning Edible coating Lipid Water in oil emulsion Electrospraying is an efficient practice for coating complex food products. Water-in-oil emulsion and chocolate based coatings were electrosprayed on food model systems (apple slices and candy tablets). The emulsion based coatings penetrated into the products, while chocolate based coating stayed on the target surfaces. These coatings were evaluated to prevent the browning and water loss from the apple slices. Emulsion based coatings were effective in preventing the browning of apple slices, depending on the composition of the continuous phase, but were unable to retard the water migration significantly owing to coating penetration inside the products, leaving a very thin film on the surface. In that respect, chocolate based coatings were more effective in reducing the water vapour flux compared to emulsion based coatings. The results indicated that solid lipid based coatings were more effective in water vapour flux reduction than liquid lipid based coatings. Industrial relevance: Electrospraying is an efficient coating technique which can reduce the processing cost for industrial processes. This technique has been successfully applied for food product to increase the shelf life of minimally processed food. The result found in this study can be used at industry to obtain food product with desired sensory attributes along with prolonged shelf life. © 2013 Elsevier Ltd. All rights reserved. 1. Introduction Minimal processed fruits and vegetables are popular with consumers who demand healthy alternatives to conventional snack foods. They are highly nutritious but mostly suffer from shorter shelf-life. Being living tissues, physiology, and biochemistry processes continue to take place after cutting, slicing, and coring or shredding. Damage to skin and cell wall, both due to handling or processing, can cause the loss of nutrients, ions, and accelerate the enzymatic reactions resulting in microbial growth, production of undesirable volatile compounds, colour & texture change, and weight loss. To avoid these, adequate processing and storage are necessary (Balla & Farkas, 2006; Raybaudi-Massilia, Mosqueda- Melgar, & Tapia, 2010; Tapia et al., 2008; Wu & Chen, 2013). The most practical and common methods used to overcome these problems and to prolong the shelf-life of fresh-cut products are modified atmosphere packaging, dipping in the solutions of antimicrobials & antioxidants, or storage at low temperature (b 5 °C). However, edible coatings, as an alternative approach, have gained much attention in the last decades. Edible coatings, from natural resources, are environmentally-friendly that can reduce the deleterious effect brought about by minimal processing and enhance the quality. Their barrier properties are aimed to extend shelf life by reducing moisture and solute migration, gaseous exchange, oxidative reaction rates, and suppressing physiological disorders on fresh-cut fruits. Moreover, edible coatings can also serve as carriers of food additives, e.g. anti- browning and antimicrobial agents, colourants, flavours, nutrients, and spices (Khan, Mujawar, Schutyser, Schroën, & Boom, 2012; Khan, Schutyser, Schroën, & Boom, 2012a; Khan, Schutyser, Schroën, & Boom, 2012b; Valencia-Chamorro, Palou, Río, & Pérez-Gago, 2011; Wu & Chen, 2013). However, specific studies on fresh-cut fruits are rather limited and their industrial implementation is still incipient (Rojas-Grau, Soliva- Fortuny, & Martın-Belloso, 2009). In fresh fruits and vegetables, weight loss and respiration rate can be reduced by using edible coatings which can also increase their visible quality. Moreover, edible coatings can partly replace synthetic packaging and may even lead to natural and biodegradable materials applied to fruits. It will reduce the packaging requirement and waste disposal problems. Edible coatings are being applied to food by spraying, dipping, and co-acervation and most recently also through, electrospraying which produces thin and uniform coating (Khan, Maan, Schutyser, Schroën, & Boom, 2013; Khan, Mujawar, Schutyser, Schroën, & Boom, 2012; Khan, Schutyser, Schroën, & Boom, 2012). In electrospraying, micro- droplets are generated by applying a potential difference over a droplet emerging from a nozzle (Jaworek, 2007, 2008). The charged droplets follow a trajectory to the nearest grounded surface as a result of electrostatic attraction, leading to a high transfer efficiency (80%) compared to conventional methods (Luo, Loh, Stride, & Edirisinghe, 2012; Maski & Durairaj, 2010; Oh, Kim, & Kim, 2008) which might reduce the processing cost. Innovative Food Science and Emerging Technologies xxx (2013) xxx–xxx ⁎ Corresponding author. Tel.: + 0232-3884000/3016. E-mail addresses: mki.khan@yahoo.com (M.K.I. Khan), sebnem.tavman@ege.edu.tr (Ş. Tavman). INNFOO-01077; No of Pages 5 1466-8564/$ – see front matter © 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ifset.2013.10.006 Contents lists available at ScienceDirect Innovative Food Science and Emerging Technologies journal homepage: www.elsevier.com/locate/ifset Please cite this article as: Khan, M.K.I., et al., Anti-browning and barrier properties of edible coatings prepared with electrospraying, Innovative Food Science and Emerging Technologies (2013), http://dx.doi.org/10.1016/j.ifset.2013.10.006