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The concern about consuming eco-friendly products has motivated research in the development of new materials. Therefore, films based on natural polymers have been used to replace traditional polymers. This study consists of a production of films based on gelatin reinforced with black pepper essential oil-loaded nanoemulsions and Cloisite Na+. The films were characterized by water vapor permeability, mechanical and thermal properties, surface contact angle, X-ray diffraction and scanning electron microscopy. It was observed that the films containing the nanoemulsion have higher permeability values and an increase in their mechanical resistance. The addition of nanoclay contributed to an increase in the surface hydrophobicity of the film and an increase in the tensile strength, at break, by about 150%. The addition of essential oil nanoemulsions led to an increase in thermal stability. The presence of clay dispersion contributed to the formation of a surface that was slightly rougher and grainier. The addition of the black pepper essential oil nanoemulsion resulted in an increase in porosity of the gelatin matrix. Through X-ray diffraction analysis, it was possible to conclude that both the polymeric gelatin matrix and the essential oils nanoemulsion are intercalated with the clay dispersion.

Every year, the residues generated by the disposal of packaging materials produced from fossil fuels have been growing, denoting a major environmental problem that can be mitigated by the development of biodegradable materials from natural polymers, particularly edible films. This work aimed at the development of pectin films added by cupuassu puree and chitosan nanoparticles and to evaluate the improvement of the physical–mechanical performance of the composite films. The nanostructures displayed an average size of 110 nm and a zeta potential of approximately +40 mV. The films were produced by casting, and they exhibited manageability, homogeneity, and continuity. Based upon the mechanical analysis of maximum stress and elongation, it was concluded that the nanoparticles functioned as fillers, increasing the toughness of the pectin films. Water vapor permeability assays demonstrated that the nanostructured films containing cupuassu exhibited improved barrier properties. The glass transition temperature of the films was not strongly affected by the addition of nanoparticles. Conversely, the initial degradation temperature decreased with the addition of nanoparticles and cupuassu puree. The outcomes of this research pave a new route for the development of nonconventional food packaging materials.

A bioactive film based on gelatin and corn starch with corn stigma extract (CSE) was developed for application to protect the quality of chilled beef. The physical and functional properties of the films were evaluated. It was found that the incorporation of CSE did not affect the thickness and moisture of the films, but reduced the solubility in water. The opacity of the active films was slightly higher than that of the control film. The incorporation of the CSE extract in the films considerably increased the bioactive and antioxidant properties. The application of CSE reduced lipid oxidation by 60% compared with the control (without additive). It is important to emphasize that the pH values remained low until the 7th day of shelf life. The active film also showed antimicrobial activity against mesophilic and psychrotrophic bacteria. The overall results emphasized the potential use of bioactive compounds from the CSE for the production of films intended for food packaging. Practical applications This study proved the antioxidant and antimicrobial action of corn stigma extract (CSE) incorporated in films to package refrigerated beef. The CSE demonstrated a strong antioxidant action, reducing lipid oxidation by 60% compared with the control, decreasing the count of mesophilic and psychrotrophic bacteria. The compiled results confirm that the active film containing CSE extract can be used as an alternative packaging.

Cellulose is everywhere and renovates in nature continuously and rapidly, while petroleum does not. Unlike the latter, cellulose biodegrades and may represent a carbon sink. Inspired by the multiscale architecture of cellulose, we report on all-cellulose composites comprising cellulose ether as a matrix and highly pure bacterial cellulose nanocrystals (BCNCs) as fillers. Optimum performance as a packaging material was achieved by engineering BCNC surface chemistry as well as the filler-in-matrix dispersion, targeting the replacement of unsustainable, fossil-derived plastics intended for single-use applications. Cost could pose a hurdle, eliminated through the valorization of underutilized scraps from industrial operations, which is also in line with the circular bioeconomy in terms of the integral use of biomass. As far as performance, the optically transparent hydroxypropyl methylcellulose (HPMC) films presented improved tensile strength (from 61 ± 6 to 86 ± 9 MPa) and Young's modulus (from 1.5 ± 0.2 to 2.7 ± 0.4 GPa) while reduced elongation at break (from 15 ± 2 to 12 ± 2%) and water vapor permeability (from 0.40 ± 0.02 to 0.31 ± 0.01 g mm h −1 m −2 kPa −1 ) when filled with only 5 wt % of (120 ± 31) nm long, (13 ± 3) nm wide, 88% crystalline BCNC. This dual, win−win effect of BCNCs on the mechanical and barrier properties of HPMC films was enabled by a suitable dispersion state, achieved via high-energy mixing, and quenched by casting. This study adds to the current literature on all-cellulose composites and helps pave the route for the technical and economical feasibilities of replacing non-renewable, non-biodegradable plastics in short-term applications by materials that are both renewable and biodegradable, that are also produced through green protocols and isolated from surplus biomass, and that still perform similarly or even better.

. The aim of this work was to produce biodegradable films based on the pectin and cocoa puree reinforced with chitosan nanoparticles. Nanoparticles were obtained by the ionotropic gelation. Films were produced according to the "casting" method, through a colloidal solution composed of water, cocoa puree, chitosan nanoparticles solution and different concentrations of pectin (2% and 3% w/w). Films were analyzed by thickness measurements, water vapor permeability, mechanical properties and scanning electron microscopy. Nanoparticles were characterized by zeta potential and showed spherical shape with a diameter of about 110 nm and zeta potential value of approximately +30 mV. Pectin 2% and 3% cocoa films exhibited tensile strength (mPa) of 15.1 ± 0.7 and 22.9 ± 1.6, respectively. After nanostructures addition, values increased to 25.2 ± 0.7 and 29.8 ± 1.3. Increasing concentration polymer and chitosan nanoparticles to improve tensile strength values. Films contained 3% of pectin exhibited more significant decrease in water vapor permeability values when chitosan nanoparticles were added, from 2.470 ± 0.101 to 1.904 ± 0.125 g mm / kPa h m 2. Results of the analyzes demonstrated that nanocomposites produced with pectin of different concentration showed satisfactory properties for application as packaging for food.Keywords: edible films; chitosan nanoparticles; pectin. INTRODUÇÃOOs resíduos gerados pelo descarte de embalagens produzidas por fontes não renováveis vêm crescendo a cada ano e constituem um grande problema do ponto de vista ambiental. Boa parte destes resíduos provém das embalagens usadas em produtos alimentícios, impulsionando pesquisas com foco no desenvolvimento de filmes comestíveis biodegradáveis obtidos através de biopolímeros. 1,2Atualmente, o mercado global vem buscando oferecer produtos e alimentos mais naturais, com mais qualidade e segurança, por conta da demanda crescente dos consumidores, que estão cada vez mais exigentes e mais preocupados com a qualidade de vida, saúde e bem-estar. Para atender às necessidades do mercado, estão sendo desenvolvidas as chamadas "embalagens ativas", que são aquelas que, além de servirem como barreira entre o meio externo e interno, exercem uma outra função na preservação do alimento. 3Filmes comestíveis podem ser uma alternativa para estender a vida de prateleira dos alimentos, servindo como barreira à passagem de gases e podendo também carrear substâncias capazes de retardar a contaminação por micro-organismos. 4,5 Os biopolímeros mais utilizados na formação dos filmes comestíveis são as proteínas, os polissacarídeos e os lipídeos. Dentre as proteínas, merecem destaque a gelatina, caseína, ovoalbumina, glúten de trigo, zeína e proteínas miofibrilares. Os polissacarídeos que se destacam são o amido, a quitosana, a pectina e a celulose. Já os lipídios, pode-se destacar o uso dos monoglicerídeos acetilados, ácido esteárico, ceras e ésteres de ácido graxo. 6 Além do componente principal para a formação da matriz polimérica, as soluções filmogênicas são constituíd...

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Recebido em 13/04/2018; aceito em 25/06/2018; publicado na web em 21/08/2018 INFLUENCE OF LEMON NANOEMULSION IN FILMS GELATIN-BASED. The development of films from natural polymers is an alternative to reduce the consumption of packaging obtained from non-renewable sources. The formation of edible films requires a polymeric material that forms a homogeneous and continuous matrix. The gelatin is a natural polymer, cheap and abundant, characteristics that instigate its use. The aim of this study was preparing and characterize gelatin films and evaluate the influence of lemon essential oil nanoemulsion on gelatin matrix for an innovative application of the product. The films were characterized for their water vapor permeability (WVP) test, contact angle, thickness and mechanical analysis (tensile strength and elongation at break). The particle size showed an average of 170.6 nm and zeta potential around -10.9 mV. The incorporation of lemon nanoemulsion increased the water vapor permeability of the gelatin and the elongation, but decreased tensile strength due to the interaction with the hydrophobic portion of the polymer matrix.Keywords: gelatin; lemon essential oil; nanoemulsion. INTRODUÇÃOO aumento da demanda por produtos saudáveis e ecologicamente corretos, assim como a preocupação com segurança alimentar e ambiental têm estimulado pesquisas de desenvolvimento de filmes a partir de biopolímeros.1-3 Atualmente, grande parte das embalagens utilizadas são de fontes não-renováveis de energia, como o petróleo, e por levarem um longo tempo para se degradarem no ambiente, causam sérios problemas de acúmulo de resíduos. 4,5 Nesse contexto, é de grande interesse a busca pela substituição de embalagens convencionais por outras que sejam biodegradáveis e até mesmo comestíveis.2,6 Diversos são os materiais obtidos de recursos renováveis que possibilitam tais inovações. Entre eles, os mais utilizados para formação de filmes comestíveis são determinados polissacarídeos, proteínas e lipídeos. 7Em relação às proteínas, a gelatina tem se mostrado promissora para formação de filmes, além de ser abundante, ter baixo custo, excelente biocompatibilidade e biodegradabilidade.8 Seu processamento é feito a partir da hidrólise controlada de colágeno fibroso insolúvel, extraído de ossos e peles de animais durante o abate.9,10 A gelatina é um biopolímero composto por sete aminoácidos diferentes, possui estrutura de tripla-hélice e temperatura de desnaturação proteica em torno de 40 °C. 11,12Em geral, filmes comestíveis sintetizados a partir de proteí-nas possuem melhores propriedades mecânicas do que filmes de lipídeos e polissacarídeos. 13 No entanto, devido à elevada natureza higroscópica e baixo ponto de fusão da gelatina a adição de outros componentes como, por exemplo, polissacarídeos, proteí-nas, lipídeos ou polímeros naturais geram filmes compostos que podem combinar vantagens e melhorias em suas propriedades. [13][14][15] O óleo essencial de limão (Citrus limon L.) adicionado a um filme polimérico pode alterar determinadas caracter...