The development of new edible coatings with improved functionality and performance for fresh and minimally processed fruits is one of the challenges of the post harvest industry. In the past few years, research efforts have focused on the design of new eco-friendly coatings based on biodegradable polymers, which not only reduce the requirements of packaging but also lead to the conversion of by-products of the food industry into value added film-forming components. This work reviews the different coating formulations and applications available at present, as well as the main results of the most recent investigations carried out on the topic. Traditionally, edible coatings have been used as a barrier to minimize water loss and delay the natural senescence of coated fruits through selective permeability to gases. However, the new generation of edible coatings is being especially designed to allow the incorporation and/or controlled release of antioxidants, vitamins, nutraceuticals, and natural antimicrobial agents by means of the application of promising technologies such as nanoencapsulation and the layer-by-layer assembly.

No effect of coatings was observed in the development of these variables. A decrease of clarity and hue values was observed during storage; the samples coated with the greatest 20 amount of propolis being the lightest. The hue decrease was related with the a* colour coordinate increase, which was significantly more accused for uncoated samples.Regardless of their composition, coatings slowed down the weight losses and controlled the oxygen consumption of the samples. At 10 days of storage, coated samples maintained a better microbial safety than uncoated samples. Although no significant 25 *Manuscript Click here to view linked References effect of the propolis incorporation was observed on the preservation of grape quality during storage, its incorporation in the HPMC coatings contributes to enrich the health characteristics of the coated product.

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ElsevierPastor Navarro, C.; Sánchez González, L.; Chiralt A.; Cháfer Nácher, MT.; González Martínez, MC. (2013). Physical and antioxidant properties of chitosan and methylcellulose based films containing resveratrol. Food Hydrocolloids. 30 (1) This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Resveratrol is a natural antioxidant found in a variety of plant species, such as grapes, 12 and could be used for minimizing or preventing lipid oxidation in food products, retarding the formation of oxidation products, maintaining nutritional quality and 14 prolonging the food shelf life. The aim of this work was to develop and characterize two different polymeric composite films (made with chitosan (CH) and methylcellulose 16 (MC)) containing different amounts of resveratrol. This compound could be incorporated efficiently into both films, but provoke structural changes in the matrices, 18 which became less stretchable (65-70% reduction of deformation at break at the greatest resveratrol content) and resistant to fracture (26 and 54% reduction of tensile at break 20 for MC and CH, respectively, at the greatest resveratrol content) more opaque (significant reduction of the internal transmittance) and less glossy (about 60-65% 22 reduction of gloss at the greatest resveratrol content ). Film barrier properties were hardly improved by the presence of resveratrol; water vapour and oxygen permeability 24 tend to slightly decrease when resveratrol was incorporated into both polymers.

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39Nowadays, the accumulation of non-biodegradable plastics is a paramount environmental 40 concern which still has not been efficiently addressed (Azeredo, 2009). Bioplastics produced from 41 renewable resources are being recognized as a solution to environmental problems concerning waste 42and dependence on fossil fuels (Byun & Kim, 2014). Starch is one of the most widely used and 43promising materials in the bioplastics market due to its biodegradability, availability, renewability and 44 low cost (Wilhelm et al., 2003; Barnett, 2011). Native starch does not have thermoplastic properties; 45 however, with the addition of plasticizers and thermal-shearing processing, native starch gelatinizes 46and turns into thermoplastic starch (TPS), from which films can be obtained by using both solution 47 casting or thermoprocessing (Zhang et al., 2014). 48Biodegradable packaging materials can additionally be carriers of antioxidant and/or 49 antimicrobial agents (Sánchez-García et al., 2008) in order to obtain active packaging products, in 50 which active compounds are released into the food or the surrounding environment (e.g. head space) 51in the package so as to extend the shelf life of food and to improve its safety and quality properties 52 (Realini & Marcos, 2014). 53Oxidation is a chemical process, slower than microbial spoilage, which lies in a primary quality antimicrobials (Gyawali & Ibrahim, 2014;Moreira et al., 2005). 71Lactoferrin and lysozyme could be used for the purposes of conferring active properties to 72 biodegradable films (Jenssen and Hancock, 2009 (Arnold et al., 1977;Reyes et al., 2005). The bactericidal effect has been 79 attributed to its direct interaction with the bacterial membranes (García-Montoya et al., 2012). 80Specifically, LF has the ability to damage the outer membrane of Gram-negative bacteria directly due 81to its interaction with lipolisacharide (LPS) (Ellison et al., 1988). The use of Lysozyme (LZ) in 82antimicrobial packaging applications has been described by several authors (Barbiroli et al., 2012; 83 Gemili et al., 2009, Buonocore et al., 2005 PS was dispersed in distilled water at 2% wt., using magnetic stirring for 5 to 10 minutes. These 127PS dispersions were heated in a thermostatic bath at 99ºC for 30 minutes and stirred every 5 minutes. 128After cooling down with running water, glycerol was added (mass ratio of glycerol to PS was 0.25:1). 129The dispersions were homogenized with a rotor stator ultraturrax D125 for 4 minutes at 13,500 rpm, 137Teflon plates (150mm diameter) were used for film casting. The mass of film forming 138 dispersions corresponding to 1.5 g of solids was cast on each plate. After drying for 48 h at 45 %RH 139and 25ºC, the films were separated from the plates. For the purposes of studying the effect of storage 140 time on the physical properties of the films, the samples were stored, at 25ºC, for 1 or 5 weeks prior to 141analyses in desiccators at 54% RH, by using an oversaturated Mg(NO3)2 solution. In order to assess 142 the role of moisture cont...

The effect of osmotic pretreatments was analyzed as a way to optimize the quality loss of pear slices (cv. Blanquilla) during dried and/or rehydration processes. Pear slices, osmotically pretreated and non‐treated were dried at 45C, until about 10% final moisture, and rehydrated at 45, 55 and 65C in water. The rehydration kinetics of air‐dried pear slices were analyzed by means of Peleg and Fick's models. Kinetics parameters obtained for both models can adequately predict the sample's behavior during rehydration process. Osmotic treatment seemed to slow down the kinetics of dried pear rehydration in terms of water gain and solute loss, with no significant effect on the final solute concentration of the fruit liquid phase. This could be related with the greater viscosity of the fruit liquid phase associated with the sugar gain during the osmotic step and the total loss of this sugar during rehydration. PRACTICAL APPLICATIONS Rehydration is a complex process and its main purpose consists of restoring the properties of the dry raw material. The capacity of the dry material to be rehydrated depends on certain intrinsic properties of the vegetal tissue and also, on how the rehydration process is carried out (process conditions) and on the previous pretreatments applied to the product. These pretreatments are usually used to obtain a better quality of the final product (i.e., better preserved from undesirable changes) and in this sense, applying an osmotic dehydration step prior to the rehydration process could be interesting. Thus, the process optimization of pretreated products, rehydrated under several conditions and pretreatments, is a desirable and useful tool to reformulate and obtain high‐quality products.