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Summary: The main objective of this study was to extract phytochemicals from carrot by‐product, encapsulate them in TPP chitosomes (consisting of liposome vesicles coated with chitosan cross‐linked with sodium tripolyphosphate) and incorporate them into chitosan (Ch) films. Physicochemical, antioxidant and antimicrobial properties of films were evaluated. Three concentrations of TPP chitosome suspension were studied: 50%, 60% and 70%, designated TPPCh50, TPPCh60 and TPPCh70 respectively. Microscopy analyses showed that the particles modified the surface and internal structures of the Ch films, providing films with higher average roughness (Control: 12.6 ± 1.8 nm vs. TPPCh70: 96.1 ± 8.0 nm) and decreased gloss (Control: 34.1 ± 3.9 GU vs. TPPCh70: 5.6 ± 1.0 GU). Furthermore, the TPPCh films displayed decreased Ch intermolecular interactions, which produced less mechanically resistant (TS = 15.3 MPa), more elongable (EB = 47.9%), slightly more water‐soluble (SI = 14.7%) and more water‐vapour permeable (WVP = 7.54*10−9 g/msPa) films, mainly at high phytochemical concentration (TPPCh70) as compared to the Control. TPPCh addition in the Ch film improved its antioxidant capacity (3.6 times greater) and UV/Vis light barrier property, but no significant antimicrobial activity was observed. In conclusion, TPPCh films could be used as packaging to preserve foods that are sensitive to oxidation. [ABSTRACT FROM AUTHOR]

The aim of the present study was to propose a new approach on the preparation of a hybrid system composed of chitosan nanoparticles (ChNps) and cellulose nanocrystals (CNCs), as carriers of folic acid (FA). ChNp was prepared by ionic gelation technique using sodium tripolyphosphate (TPP) as crosslinker and CNCs from soybean pods, extracted by chemical pre-treatments and acid hydrolysis. The microscopic observation revealed clusters of fibers amongst the ChNps, arranged in a three-dimensional network as large as 1 to 3 µm in diameter. Zeta potential measurements of the particle suspensions loaded with FA did not differ significantly from those read for empty ChNps (both samples with values around + 23 to + 25 mV). The CNC hybrid system presented higher efficiency of encapsulation (72 ± 8%), compared to cross-linked ChNp system which has no fibers added (62 ± 4%). Moreover, the FA releasing (at pH 3.0 and 7.4) and the protection against light degradation were higher in the hybrid systems. Infrared spectroscopic and thermogravimetric analysis showed a better maintenance of the main vitamin structure when encapsulated by the composite particles. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carrot by-products were used to extract bioactive compounds using green technology. • Bioactives were encapsulated in liposomes, chitosomes and TPP-chitosomes. • TPP-chitosomes had lower tendency of agglomeration after 18 days of preparation. • TPP-chitosomes were the most effective to protect carotenoid-rich extract. The objectives of this study were to extract bioactive compounds from carrot by-products and evaluate their chemical stability after encapsulation in liposomes (L) coated either with chitosan (Ch) or using sodium tripolyphosphate for chitosan complexation (TPP-Ch). The main compounds quantified in this study were carotenoids and total phenolic compounds, which reached encapsulation efficiencies higher than 75%. The TPP-Ch charged with carrot extract showed greater particle size (90.5 nm) and zeta potential (+22 mV) than vesicles without coating (68.0 nm and −2 mV, respectively), indicating that liposomes were successfully coated with chitosan. Regarding results of the carotenoid's encapsulated stability, TPP-Ch particles were more efficient preventing their degradation in all the experimental conditions studied (40 and 70 °C). It is significant that loaded TPP-Ch particles demonstrated similar results for the stability of carotenoid-rich extracts in ethanol, which would therefore be suitable for application in food industry or any aqueous matrices. [ABSTRACT FROM AUTHOR]

• Chitosan solution was directly used for polyphenol extraction from by-products. • Chitosan as solvent facilitates the follow-up encapsulation process. • Active loaded particles attained 52% of encapsulation efficiency. • Active coatings have a potential for extending the shelf life of guavas. Aiming the simplification of the production of chitosan nanoparticles as an encapsulating material, the primary approach of this study was to investigate the extraction of active compounds from acerola-pulp by-products directly in chitosan solution by using tip sonication. The results have shown that chitosan solution can be used as a good solvent, mainly for total phenolic compounds (TPC) extraction (1792.7 mg/100 g of dry by-product). The extract was submitted to ionic gelation process using, as counter-ion, the sodium tripolyphosphate to form loaded nanoparticles with TPC. The suspension was applied as protective coatings on the guavas. The nanoengineered coatings provided an effective barrier that delayed the maturation and maintained the green pigmentation for longer periods along with good firmness. To the best of our knowledge, this was the first study that uses chitosan solution as extraction solvent of TPC from food byproducts in order to facilitate the encapsulation process. [ABSTRACT FROM AUTHOR]