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Transport mechanism of macromolecules on hydrophilic bio-polymeric matrices : d...

The transport mechanism of protein-based bioactive compounds (a peptide fraction from whey protein concentrate, glycomacropeptide and lactoferrin), from chitosan films to liquid medium, was studied. Mathematical models were used to discuss the transport mechanism. Data from release experiments was successfully described by a model which accounts for both Fick and Case II transport – the linear superimposition m...

Molecular mobility, composition and structure analysis in glycerol plasticised ...

This study was developed with the purpose to investigate the effect of polysaccharide/plasticiser concentration on the microstructure and molecular dynamics of polymeric film systems, using transmission electron microscope imaging (TEM) and nuclear magnetic resonance (NMR) techniques. Experiments were carried out in chitosan/glycerol films prepared with solutions of different composition. The films obtained aft...

Κ-carrageenan/chitosan nanolayered coating for controlled release of a model bi...

Multilayer nanocoatings composed of κ-carrageenan, a sulphated anionic polysaccharide, and chitosan, a cationic polysaccharide, were produced by layer-by-layer deposition. The model cationic compound Methylene Blue (MB) was incorporated in different positions of the nanolayered coating and its loading and release behavior was evaluated. UV–VIS spectroscopy and quartz crystal microbalance analysis showed that th...

Evaluation of a hydrothermal process for pretreatment of wheat straw : effect o...

Hydrothermal processes are an eco-friendly processes that provide an interesting alternative for chemical utilization of lignocellulosic materials, in which water and crop residues are the only reagents. In this work the effect of process conditions (size distribution of the wheat straw, temperature and time) was evaluated against production of fermentable products. RESULTS: The use of milled wheat straw fracti...

Nanoemulsions of β-carotene using a high-energy emulsification-evaporation tech...

Nanoemulsions of β-carotene were prepared using a high-energy emulsification-evaporation technique based on a 23 level factorial design. Results show that it is possible to obtain dispersions at a nanoscale range. Process parameters such as time and shear rate of homogenization affected significantly particle size distribution in terms of volume-weighted mean diameter and surface-weighted mean diameter. The obt...

Physico-chemical characterization of chitosan-based edible films incorporating ...

Chitosan packaging films containing different bioactive compounds (a peptide fraction from whey protein concentrate (WPC) hydrolysate, glycomacropeptide (GMP) and lactoferrin) were produced and their mechanical and barrier properties were evaluated. The molecular weight of protein-based compounds was determined using SDS–PAGE. The addition of GMP and lactoferrin to chitosan film caused a significant reduction o...

Antioxidant potential of two red seaweeds from the Brazilian coasts

In this work, in vitro antioxidant activity of two Brazilian red seaweeds, Gracilaria birdiae and Gracilaria cornea, was characterized. The total phenolic content, the radical-scavenging activity and the antioxidant activity were determined in two solvent extracts of the algae. Liquid chromatography mass spectrometry (LC MS/MS) allowed identification of important antioxidant compounds. The ethanol extract of G....

Physical and thermal properties of a chitosan/alginate nanolayered PET film

Nanolaminates have been reported to have applications in different areas, such as the preparation of multilayer films, coating biomedical appliances or multilayer edible coatings with enhanced properties for applications in the food industry. This work aims at characterizing the surface properties, water vapor permeability, and thermal and mechanical properties of a nanolayered film. The film was produced using...

Sucrose in the concentrated solution or the supercooled “state” : a review of c...

Sucrose is probably one of the most studied molecules by food scientists, since it plays an important role as an ingredient or preserving agent in many formulations and technological processes. When sucrose is present in a product with a concentration near or greater than the saturation point—i.e. in the supercooled state—it possesses high potentialities for the food industry in areas as different as pastry ind...

Nano structures for food applications