Over the last years, considerable research has been conducted to develop and apply edible films and coatings made from a variety of agricultural commodities and/or wastes of food product industrialization. Such biopolymers include polysaccharides, proteins, and their blends. These materials present the possibility of being carriers of different additives, such as antimicrobial, antioxidant, nutraceuticals, and flavorings agents. In particular, the use of edibles films and coatings containing antimicrobials has demonstrated to be a useful tool as a stress factor to protect foodstuff against spoilage flora and to decrease the risk of pathogen growth. The more commonly antimicrobials used are organic acids, chitosan, nisin, the lactoperoxidase system, and some plant extracts and their essential oils. For the selection of an antimicrobial, it must be considered the effectiveness against the target microorganism and also the possible interactions among the antimicrobial, the film-forming biopolymer, and other food components present. These interactions can modify the antimicrobial activity and the characteristics of the film being these key factors for the development of antimicrobial films and coatings. The main objective of this article is to review the bibliography of the last years concerning the main hydrocolloids and antimicrobials used for developing edible films and coatings, the methods used to evaluate the antimicrobial activity, the applications and the legislation concerning edible films and coatings. Also, the different strategies related to the modification of structural characteristics and the future trends in the development are discussed. The information update will help to improve the design, development, and application of edible films and coatings tending to increase the safety and quality of food products and to prepare for food legislation changes that might be necessary while identifying future trends concerning a better functionality of edible films thought as a stress factor for lengthening shelf life of food products.

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The enormous quantity of food wastes discarded annually forces a look into alternatives for this interesting feedstock.

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In this study, the effects of cooling rate, degree of supercooling, and storage time on the microstructure and rheological properties of a vegetable shortening composed of soybean and palm oils were examined. The solid fat content vs. temperature profile displayed two distinct regions: from 5 to 25°C, and from 25°C to the end of melt at 45-50°C. A peak melting temperature of 42.7°C was determined by DSC. Discontinuity in the crystallization induction time (determined by pulsed NMR) vs. temperature plot at 27°C also suggested the existence of two separate groups of crystallizing material. Isothermal crystallization kinetics were characterized using the Avrami and Fisher-Turnbull models. In using DSC and powder X-ray diffraction, the α polymorph formed upon fast cooling (>5°C/min), and the β′ form predominated at lower cooling rates (<1°C/min). An α to β′ transition took place upon storage. Fractal dimensions (D f ) obtained by microscopy and image analysis showed no dependence on the degree of supercooling since D f remained constant (~1.89) at crystallization temperatures of 5, 22, and 27°C. Crystallization at 22°C at 1°C/min and 15°C/min yielded D f values of 1.98 and 1.93, respectively. Differences in microstructure were observed, and changes in particle properties increased the parameter λ at higher degrees of supercooling.Hydrogenation of unsaturated FA in edible oils allows for the conversion of liquid oils into semisolid fats. These fats are characterized by altered melting and textural characteristics and by a higher oxidative stability. Modified plastic vegetable fats are often the key ingredients in margarines and specialty tailored fats like shortening (1).Shortenings are commonly used in dough formulations where the fats need to be mixed with other ingredients at room temperature and possess a high level of stability at elevated baking temperatures. Therefore, a smooth material that is spreadable at room temperature and has a specific melting profile, solid fat content (SFC), and polymorphic behavior is desired.It is well known that the solid-like behavior of plastic fats is due to the presence of a fat crystal network (2-5). The influence of microstructure on the macroscopic rheological properties of shortening is therefore the focus of this study. The nature of this crystal network, including its spatial distribution, and the number, size, and shape of its constituent microstructural elements can be dramatically altered by changes in crystallization conditions. Effects of cooling rate, the degree of supercooling, and storage time on crystallization and melting behavior and mechanical properties, including the storage modulus (G′) and loss modulus (G″), were investigated. Powder X-ray diffraction (XRD) spectroscopy and DSC were also used to investigate the effects of various crystallization conditions on polymorphism in the shortening. MATERIALS AND METHODS Sample and chemicals.A commercially available allvegetable oil-based shortening (Golden Crisco Doré, Procter & Gamble, Toronto, Ontario, Canada) c...