The Experts below are selected from a list of 3111 Experts worldwide ranked by ideXlab platform
Andree Voilley - One of the best experts on this subject based on the ideXlab platform.
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moisture barrier wetting and mechanical properties of Shellac agar or Shellac cassava starch bilayer bio membrane for food applications
Journal of Membrane Science, 2008Co-Authors: Frederic Debeaufort, Andree VoilleyAbstract:Abstract Edible bilayer membrane composed of agar (AG) or cassava starch (CAS) as a cohesive structural layer and ethanol-cast Shellac layer as a moisture barrier are investigated for their potential use in food preservation as bio-packaging film, membrane or coating. Bilayer membranes containing non-plasticized Shellac exhibit low water vapor permeability (WVP), from 0.89 to 1.03 × 10 −11 g m −1 s −1 Pa −1 . A high value of contact angle (≈92°) and a low liquid water adsorption rate (26 × 10 −3 μL s −1 ) indicate that these barrier layers have a quite hydrophobic surface. However, the rigid and brittle characteristics of Shellac induce a lack of integrity for this layer. It tends to be cracked and scaled off. The incorporation of PEG 200 (plasticizer) into Shellac improves the flexibility that prevents the defects in structure and reinforces the adhesion between the Shellac and the cohesive-structural layer. The use of plasticizer weakly affects the WVP of bilayer membranes; however, the surface hydrophobicity as well as the liquid water adsorption rate is comparable to that of non-plasticized Shellac layer. Furthermore, PEG increases the stretchability of bilayer membranes. Either being plasticized or not, Shellac layer could improve significantly the functional properties of bilayer barriers and give a promising use as biopackaging.
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Moisture barrier, wetting and mechanical properties of Shellac/agar or Shellac/cassava starch bilayer bio-membrane for food applications
Journal of Membrane Science, 2008Co-Authors: Frederic Debeaufort, D. Luu, Andree VoilleyAbstract:Abstract Edible bilayer membrane composed of agar (AG) or cassava starch (CAS) as a cohesive structural layer and ethanol-cast Shellac layer as a moisture barrier are investigated for their potential use in food preservation as bio-packaging film, membrane or coating. Bilayer membranes containing non-plasticized Shellac exhibit low water vapor permeability (WVP), from 0.89 to 1.03 × 10 −11 g m −1 s −1 Pa −1 . A high value of contact angle (≈92°) and a low liquid water adsorption rate (26 × 10 −3 μL s −1 ) indicate that these barrier layers have a quite hydrophobic surface. However, the rigid and brittle characteristics of Shellac induce a lack of integrity for this layer. It tends to be cracked and scaled off. The incorporation of PEG 200 (plasticizer) into Shellac improves the flexibility that prevents the defects in structure and reinforces the adhesion between the Shellac and the cohesive-structural layer. The use of plasticizer weakly affects the WVP of bilayer membranes; however, the surface hydrophobicity as well as the liquid water adsorption rate is comparable to that of non-plasticized Shellac layer. Furthermore, PEG increases the stretchability of bilayer membranes. Either being plasticized or not, Shellac layer could improve significantly the functional properties of bilayer barriers and give a promising use as biopackaging.
Stéphane Desobry - One of the best experts on this subject based on the ideXlab platform.
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physico chemical properties of alginate Shellac aqueous core capsules influence of membrane architecture on riboflavin release
Carbohydrate Polymers, 2016Co-Authors: Ghazi Ben Messaoud, Laurent Probst, Carole Jeandel, Laura Sanchezgonzalez, Elmira Arabtehrany, Stéphane DesobryAbstract:To enhance physico-chemical properties of alginate liquid-core capsules, Shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, Shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that Shellac significantly influenced the capsules properties. The feasibility of Shellac incorporation was closely related to the preparation conditions as confirmed by Infrared spectroscopy. Optical, fluorescence and scanning electron microscopy, highlighted different capsules and membranes architectures. In contrast to simple and composite capsules, coated capsules showed a pH-dependent release of the entrapped vitamin especially after Shellac crosslinking with calcium. Heating of coated capsules above the glass transition temperature investigated by Differential Scanning Calorimetry, led to irreversible structural change due to thermoplastic behavior of Shellac and enhanced riboflavin retention under acidic conditions. This global approach is useful to control release mechanism of low molecular weight molecules from macro and micro-capsules.
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Physico-chemical properties of alginate/Shellac aqueous-core capsules: Influence of membrane architecture on riboflavin release.
Carbohydrate Polymers, 2016Co-Authors: Ghazi Ben Messaoud, Laura Sánchez-gonzález, Laurent Probst, Carole Jeandel, Elmira Arab-tehrany, Stéphane DesobryAbstract:To enhance physico-chemical properties of alginate liquid-core capsules, Shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, Shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that Shellac significantly influenced the capsules properties. The feasibility of Shellac incorporation was closely related to the preparation conditions as confirmed by Infrared spectroscopy. Optical, fluorescence and scanning electron microscopy, highlighted different capsules and membranes architectures. In contrast to simple and composite capsules, coated capsules showed a pH-dependent release of the entrapped vitamin especially after Shellac crosslinking with calcium. Heating of coated capsules above the glass transition temperature investigated by Differential Scanning Calorimetry, led to irreversible structural change due to thermoplastic behavior of Shellac and enhanced riboflavin retention under acidic conditions. This global approach is useful to control release mechanism of low molecular weight molecules from macro and micro-capsules.
Frederic Debeaufort - One of the best experts on this subject based on the ideXlab platform.
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moisture barrier wetting and mechanical properties of Shellac agar or Shellac cassava starch bilayer bio membrane for food applications
Journal of Membrane Science, 2008Co-Authors: Frederic Debeaufort, Andree VoilleyAbstract:Abstract Edible bilayer membrane composed of agar (AG) or cassava starch (CAS) as a cohesive structural layer and ethanol-cast Shellac layer as a moisture barrier are investigated for their potential use in food preservation as bio-packaging film, membrane or coating. Bilayer membranes containing non-plasticized Shellac exhibit low water vapor permeability (WVP), from 0.89 to 1.03 × 10 −11 g m −1 s −1 Pa −1 . A high value of contact angle (≈92°) and a low liquid water adsorption rate (26 × 10 −3 μL s −1 ) indicate that these barrier layers have a quite hydrophobic surface. However, the rigid and brittle characteristics of Shellac induce a lack of integrity for this layer. It tends to be cracked and scaled off. The incorporation of PEG 200 (plasticizer) into Shellac improves the flexibility that prevents the defects in structure and reinforces the adhesion between the Shellac and the cohesive-structural layer. The use of plasticizer weakly affects the WVP of bilayer membranes; however, the surface hydrophobicity as well as the liquid water adsorption rate is comparable to that of non-plasticized Shellac layer. Furthermore, PEG increases the stretchability of bilayer membranes. Either being plasticized or not, Shellac layer could improve significantly the functional properties of bilayer barriers and give a promising use as biopackaging.
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Moisture barrier, wetting and mechanical properties of Shellac/agar or Shellac/cassava starch bilayer bio-membrane for food applications
Journal of Membrane Science, 2008Co-Authors: Frederic Debeaufort, D. Luu, Andree VoilleyAbstract:Abstract Edible bilayer membrane composed of agar (AG) or cassava starch (CAS) as a cohesive structural layer and ethanol-cast Shellac layer as a moisture barrier are investigated for their potential use in food preservation as bio-packaging film, membrane or coating. Bilayer membranes containing non-plasticized Shellac exhibit low water vapor permeability (WVP), from 0.89 to 1.03 × 10 −11 g m −1 s −1 Pa −1 . A high value of contact angle (≈92°) and a low liquid water adsorption rate (26 × 10 −3 μL s −1 ) indicate that these barrier layers have a quite hydrophobic surface. However, the rigid and brittle characteristics of Shellac induce a lack of integrity for this layer. It tends to be cracked and scaled off. The incorporation of PEG 200 (plasticizer) into Shellac improves the flexibility that prevents the defects in structure and reinforces the adhesion between the Shellac and the cohesive-structural layer. The use of plasticizer weakly affects the WVP of bilayer membranes; however, the surface hydrophobicity as well as the liquid water adsorption rate is comparable to that of non-plasticized Shellac layer. Furthermore, PEG increases the stretchability of bilayer membranes. Either being plasticized or not, Shellac layer could improve significantly the functional properties of bilayer barriers and give a promising use as biopackaging.
Sontaya Limmatvapirat - One of the best experts on this subject based on the ideXlab platform.
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Optimum condition of conventional bleaching process for bleached Shellac
Journal of Food Process Engineering, 2019Co-Authors: Suthep Saengsod, Sontaya Limmatvapirat, Manee Luangtana-ananAbstract:Bleached Shellac has attracted wide interest in many industries. Since bleaching using sodium hypochlorite is a vigorous process, it can possess a high impact on physicochemical properties causing the unstable bleached‐Shellac. An investigation into optimum conditions of the bleaching process was, therefore, required to achieve sufficient whiteness, good mechanical properties, and the stable bleached‐Shellac. The studied conditions were variations in solvents, volume, and time of bleaching. Studied parameters, such as color change, acid value, insoluble solid, polarity, water vapor permeability coefficient, mechanical properties, chemical structure, and crystallinity, were detected. The physicochemical properties depended on the bleaching conditions but no effect on the chemical and amorphous structures of Shellac. With the proper control of bleaching process, the simple, and conventional method can be applied in bleaching. The optimum condition was the use of sodium carbonate as a solvent, 20‐ml sodium hypochlorite, and 2‐hr bleaching time. PRACTICAL APPLICATIONS: Shellac has long been used as an edible coating for extending product quality. Although Shellac possesses an outstanding property in moisture protection, the dark color causes an unpleasant for applying in food and pharmaceutical industries. The bleaching process using sodium hypochlorite is commonly used to whiten the Shellac. Due to the vigorous redox reaction of process, extreme changes in properties of Shellac were obtained. The aim was to explore the optimum condition of bleaching process. The studied conditions were, solvent used, amount, and time of bleaching process. With a careful control of process, not only provided a high degree of whiten Shellac but also obtained good physicochemical properties of bleached Shellac. This study could be of help in adding the value of natural polymer without the use of high temperature and power consumption compared with other methods. The bleached Shellac can then be used in wider applications.
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Enhanced Mechanical Properties of Shellac Films by Incorporation of Modified Coconut Oil
Advanced Materials Research, 2014Co-Authors: Potchaman Sittipaisankul, Chutima Limmatvapirat, Manee Luangtana-anan, Sontaya LimmatvapiratAbstract:The purpose of this study was to evaluate the effect of modified coconut oil (MCO) on elasticity change of films prepared from Shellac. The MCO was added into Shellac solution and then cast to thin film. The film containing MCO from 0-30% w/w was then comparatively evaluated. The result indicated that MCO had an direct effect on mechanical properties of films. The percentage elongation was increased while the tensile strength was decreased, as increasing percentage of MCO, suggesting the reduced brittleness of film. The FTIR peak assigned to O-H and C-O stretching was also shift after incorporation of MCO. Therefore, the plasticization of Shellac film might due to the interaction between hydroxyl group of glycerides in MCO and Shellac molecules.
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A New Approach for the Preparation of Bleached Shellac for Pharmaceutical Application: Solid Method
Advanced Materials Research, 2012Co-Authors: Suthep Saengsod, Sontaya Limmatvapirat, Manee Luangtana-ananAbstract:With increased awareness about the environment, raw materials from petroleum based synthetics and the "green" quotient of consumer products have developed, Shellac or Shellac modified resins have gained importance due to their unique nontoxic and hypoallergenic properties. Shellac is water soluble, biologically degradable and has film forming, excellent adhesion, hardness, high gloss and superior in electrical properties. Shellac or Shellac modified resins are also compatible with other resins and can be cross linked making them a wider applications. Shellac is abundant in Thailand, China and India, which produced from lac insects, Laccifer Lacca. The resinous secretion can be purified to become Shellac. The main structure of Shellac consists of polyesters and single esters that have hydroxyl and carboxyl groups [1, . Shellac was first used as a wood polish for music instruments and furniture and later for uses in spar varnishes with antifouling properties for ship paints, phonographic records, wood and wallpaper paints, printing inks, resins for electrical applications and floor polishes. Currently, new applications for using are such as child-safe paints and inks and the coating of fruits and vegetables, food and confectionary, pills, tablets and vitamins in the pharmaceutical industries. Bleached Shellac has been widely used in pharmaceutical and cosmetics instead of native Shellac due to the whiteness. However, conventional method for bleached Shellac used many solvents [3, . Therefore, the aim of this study was to explore a new technique in order to avoid the use of organic solvent prior to the process of bleaching. The comparison was made between bleaching by the conventional and the new methods. The studied properties were acid value, viscosity, color change, water vapor permeability, chemical structure and powder x-ray diffraction.
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fabrication of thermally stabilized Shellac through solid state reaction with phthalic anhydride
Materials Letters, 2011Co-Authors: Danuch Panchapornpon, Chutima Limmatvapirat, Jurairat Nunthanid, Manee Luangtanaanan, Pornsak Sriamornsak, Sontaya LimmatvapiratAbstract:Abstract Shellac has been regarded as an obsolete polymer due to its poor thermal stability. The purpose of the study was to solve the problem by solid-state synthesis of Shellac phthalate (SHL–PHT). Shellac was ground with phthalic anhydride and then thermally activated at various conditions. The solid-state esterification of Shellac was clearly observed after annealing. As indicated by an increase of acid value, the esterification was more pronounced after the increase of annealing temperature and time. The formation of SHL–PHT was confirmed by FTIR spectra and other characterization techniques. The SHL–PHT demonstrated to improve the thermal stability as compared to native Shellac. After aging at high temperature, percent insoluble solid and acid value of the native Shellac dramatically changed while those of SHL–PHT were relatively the same as initial value, especially for the more esterified SHL–PHT. The protection of hydroxyl groups of Shellac by phthalate moieties might be a possible explanation for the improved stability. In conclusion, the study may give an eco-friendly way to synthesize the Shellac derivatives for future applications.
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Effect of molecular weight and concentration of polyethylene glycol on physicochemical properties and stability of Shellac film.
Journal of agricultural and food chemistry, 2010Co-Authors: Manee Luangtana-anan, Jurairat Nunthanid, Sontaya LimmatvapiratAbstract:The effects of molecular weight and concentration of plasticizer on physicochemical properties and stability of Shellac films were investigated. Type of plasticizer was previously reported to have some effects on the stability of Shellac films, and polyethylene glycol (PEG) was the plasticizer of choice for plasticizing Shellac films. In this study, different molecular weights of PEG (200, 400 and 4000) were chosen at a concentration of 10% w/w of Shellac films. Shellac in alcohol was prepared in a free film. The stability of Shellac film was then performed at 75% RH, 40 °C for 3 months. The comparison was made between the film with and without plasticizer. Shellac films were then determined for acid value, insoluble solid, mechanical properties and water vapor permeability coefficient. It was reported that different molecular weights of PEG had some influence on physicochemical properties of the Shellac films. Among different molecular weights of PEG, PEG 400 showed a suitable molecular weight that could protect the Shellac chain at the carboxylic and hydroxyl groups. Therefore, the molecular weight of plasticizer played a crucial role for the protective ability at active sites. Further study was performed to investigate the effect of concentrations of PEG 400 on the stability. The results demonstrated that PEG 400 at a concentration of 10% (w/w) could prevent the polymerization process for only 4 months and a significant change of all parameters was then reported. However, a higher concentration, 20% (w/w) of PEG 400, could prolong the stability of Shellac for 6 months of study. Therefore, the drawback of Shellac as a natural polymer in pharmaceutical and food industries could be tackled by the appropriate size and concentration of plasticizer.
Ghazi Ben Messaoud - One of the best experts on this subject based on the ideXlab platform.
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physico chemical properties of alginate Shellac aqueous core capsules influence of membrane architecture on riboflavin release
Carbohydrate Polymers, 2016Co-Authors: Ghazi Ben Messaoud, Laurent Probst, Carole Jeandel, Laura Sanchezgonzalez, Elmira Arabtehrany, Stéphane DesobryAbstract:To enhance physico-chemical properties of alginate liquid-core capsules, Shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, Shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that Shellac significantly influenced the capsules properties. The feasibility of Shellac incorporation was closely related to the preparation conditions as confirmed by Infrared spectroscopy. Optical, fluorescence and scanning electron microscopy, highlighted different capsules and membranes architectures. In contrast to simple and composite capsules, coated capsules showed a pH-dependent release of the entrapped vitamin especially after Shellac crosslinking with calcium. Heating of coated capsules above the glass transition temperature investigated by Differential Scanning Calorimetry, led to irreversible structural change due to thermoplastic behavior of Shellac and enhanced riboflavin retention under acidic conditions. This global approach is useful to control release mechanism of low molecular weight molecules from macro and micro-capsules.
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Physico-chemical properties of alginate/Shellac aqueous-core capsules: Influence of membrane architecture on riboflavin release.
Carbohydrate Polymers, 2016Co-Authors: Ghazi Ben Messaoud, Laura Sánchez-gonzález, Laurent Probst, Carole Jeandel, Elmira Arab-tehrany, Stéphane DesobryAbstract:To enhance physico-chemical properties of alginate liquid-core capsules, Shellac was incorporated into the membrane (composite capsules) or as an additional external layer (coated capsules). The influence of pH, coating time, Shellac concentration and preparation mechanism (acid or calcium precipitation) were investigated. Results showed that Shellac significantly influenced the capsules properties. The feasibility of Shellac incorporation was closely related to the preparation conditions as confirmed by Infrared spectroscopy. Optical, fluorescence and scanning electron microscopy, highlighted different capsules and membranes architectures. In contrast to simple and composite capsules, coated capsules showed a pH-dependent release of the entrapped vitamin especially after Shellac crosslinking with calcium. Heating of coated capsules above the glass transition temperature investigated by Differential Scanning Calorimetry, led to irreversible structural change due to thermoplastic behavior of Shellac and enhanced riboflavin retention under acidic conditions. This global approach is useful to control release mechanism of low molecular weight molecules from macro and micro-capsules.
