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Chitosan prepared through a mild process using 10% NaOH during deacetylation and a protein concentrate (PCc) obtained from shrimp waste was used to develop active films. Film forming solutions were prepared by solubilizing chitosan with lactic acid without plasticizers addition. The structural properties of films, as observed by optical microscopy, Cryo-SEM, DSC and FTIR, were strongly affected by the addition of the PCc. Films with added PCc were much more tensile resistant but less deformable upon perforation. The presence of PCc also improved film barrier to the light. The films showed good antioxidant and antimicrobial properties, enhanced by the incorporation of PCc. The significance of these films lies in the fact that proteins do not usually appear to enhance antimicrobial properties, and therefore this is especially useful for food applications. [ABSTRACT FROM AUTHOR]

Abstract: Active biodegradable bilayer films based on soy protein isolate, lignin and formaldehyde were developed. These films showed high water resistance and malleability, making them suitable for use in extreme environmental conditions. The presence of lignin in the formulation provided greater protection against light, especially UV. With the addition of 3% w/w citronella essential oil, the films showed good antifungal activity against Fusarium oxysporum pathogen microorganism in bananas. When the bananas were covered by the films during storage, there was a noticeable reduction in total aerobic mesophiles and moulds and yeasts. As the films aged (1, 3, 6 months), in both controlled and environmental conditions, the main active compounds in the citronella essential oil, citronellal and geraniol, were progressively released from the film matrix, citronellal more than geraniol. Over 30 days of soil degradation, the films lost around 30% of weight irrespective of the conditioning time. [Copyright &y& Elsevier]

Abstract: Several shrimp active materials, including protein concentrates, protein hydrolysates and a carotenoid extract, were recovered from shrimp (Litopenaeus vannamei) processing residues (head and exoskeleton) and characterized in terms of chemical composition and antioxidative properties (Ferric ion reducing power and ABTS radical scavenging capacity). Different coating solutions were prepared by solubilizing chitosan, which was obtained from the residual chitinous material, in lactic acid and blending it with the various recovered materials. Chitosan-based solutions were tested for their viscosity and their antioxidative and antimicrobial properties against 26 selected microbial strains. All blend solutions showed higher antioxidant capacity and reduced viscosity as compared to the base chitosan solution. The incorporation of an astaxanthin-rich protein concentrate increased the antimicrobial capacity of the blend solution, but no further effect was observed after extra addition of the carotenoid extract. [Copyright &y& Elsevier]

Physico-chemical, functional properties, and filmogenic characteristics were determined in pulp (P) and whole (W) banana flours (BF), pretreated or not (preT and unT, respectively) with sodium metabisulfite, obtained from cultivars of Ecuadorian Musaceae: Musa acuminata AAA. The proximal composition revealed a high content of fat, protein, ash, and fiber in whole banana flours, while the total starch and amylose content was greater in pulp flours. The starch granules of both pulp and whole green banana flours presented an elongated and lenticular sizes and shapes, which could be related to the amount and variations in amylose and amylopectin structure in the raw materials. Pretreatment with metabilsulfite favors the increase in L* and b* parameters, while a* is reduced; likewise, the presence of the peel tends to darken the untreated flours. Water absorption, solubility and swelling capacity rose above 70 °C, matching the gelatinization temperature observed by DSC (74–78 °C). The temperature of gelatinization was higher for the pretreated whole banana flour, noticeably, the highest enthalpy ΔH gel (32.23 Jg-1) corresponded to the untreated whole banana flour. All banana flours had the ability to form filmogenic suspensions that showed a similar pseudoplastic behavior regardless of the flour composition, except for the pretreated pulp flour, which showed less shear thinning. The viscosity recovery capacity with the decrease in temperature was almost total in the untreated samples, while in the treated samples was lower (~20%). The higher amount of amylopectin favored the viscoelastic properties in the filmogenic suspension, while the lower content of this compound diminished these properties. For the aforementioned, green banana flours are an ingredient of interest and their ability to form filmogenic solutions can be a good alternative for its subsequent industrial application. [Display omitted] • Pulp or whole Ecuadorian green banana flours (M. acuminata AAA) was obtained. • Metabisulphite pretreatments avoids darkening of flours by drying process. • Pulp flour showed less swelling than whole banana flour. • Fiber modifies rheological properties, mainly reducing elastic behavior. • Filmogenic dispersions from banana flours form structured and stable gels matrices. [ABSTRACT FROM AUTHOR]