a b s t r a c tThe manufacture of composite biofilms of alginate and LM-pectin crosslinked with calcium ions requires a two-step contact with Ca 2+ : initially a low-structured pre-film is formatted which is further crosslinked in a second contact with a more concentrated Ca 2+ solution containing plasticizer. This research evaluated the influence of the plasticizer (glycerol) concentration (1-15% w/v) in this finishing reticulation step on final films characteristics. The results indicated that the extent of the simultaneous Ca 2+ crosslinking and plasticization with glycerol was determined by the level of structural organization obtained in the pre-reticulation. Increasing the glycerol concentration of the crosslinking solution increased film solubility in water, moisture content, volumetric swelling and flexibility and decreased the resistance to tensile stress. Transparent alginate and pectin composite films with acceptable mechanical properties, low solubility and limited degree of swelling were obtained with 10% glycerol in the second contact solution.

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Biopolymeric chitosan is considered a promising encapsulating agent for textile applications due to its biocompatibility, lack of toxicity, antibacterial activity, high availability, and low cost. After cellulose, it is nature's most important organic compound. Also, chitosan has unique chemical properties due to its cationic charge in solution. Microencapsulation technologies play an important role in protecting the trapped material and in the durability of the effect, controlling the release rate. The application of chitosan microcapsules in textiles follows the current interest of industries in functionalization technologies that give different properties to products, such as aroma finish, insect repellency, antimicrobial activity, and thermal comfort. In this sense, methods of coacervation, ionic gelation, and LBL are presented for the production of chitosan-based microcapsules and methods of textile finishing that incorporate them are presented, bath exhaustion, filling, dry drying cure, spraying, immersion, and grafting chemical. Finally, current trends in the textile market are identified and guidance on future developments.

The preparation of alginate films with suitable properties requires a two-step contact with reticulating agents: initially a weakly structured pre-film is formatted which is further crosslinked in a second stage by immersion in a more concentrated solution. The present work evaluated the effects of a combined crosslinking procedure using calcium and barium ions on the physical and morphological properties of alginate-based films containing natamycin as antimicrobial agent. The release behavior of natamycin in water was evaluated as well as the antimicrobial activity against four target microorganisms, which are common cheese product contaminants. Films attributes were affected by the type of ion used in the second stage while the natamycin release rate and the antimicrobial activity were influenced by the ion used in the first stage. Films crosslinked with Ba 2þ in the first and Ca 2þ in the second stage (BaeCa films) exhibited physical properties very similar to films crosslinked with calcium in both stages. Release kinetics of natamycin in water fitted well to Fick's second law diffusional model, with effective diffusivity values ranging from 0.40 Â 10 À11 to 1.74 Â 10 À11 cm 2 /s. BaeCa films presented the lowest natamycin diffusion coefficient and the smallest inhibition zone diameter against the four microorganisms tested.