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New biodegradable film produced from cocoa shell nanofibrils containing bioactive compounds

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Abstract

Cellulosic nanofibrils from cocoa shells were used in this study to produce biodegradable films from a residue naturally rich in bioactive compounds, while reserving these compounds. The nanofibrils were obtained by mechanical defibrillation without chemical or enzymatic pretreatment. The nanofibril gel was evaluated in biodegradable films, for the first time, with the addition of glycerol as a plasticizer in the proportions of 0, 1, 3, 5, and 7% (w/w). The morphological characteristics, thermal analysis, mechanical properties (rupture tensile, maximum rupture elongation, and Young’s modulus), water vapor permeability, and water solubility of the films were investigated. In addition, the residue was analyzed and compared to the films by the FTIR technique to prove the maintenance of functional groups characteristic of antioxidant activity. The use of 3% and 5% glycerol as a plasticizer showed the best mechanical characteristics—reduced water vapor permeation and increased degradation in water. The pure nanofibril film demonstrated greater thermal stability. It was possible to identify the maintenance of aromatic groups and phenols in the residue from all cocoa shell nanofibril films. This study contributes to the future application of cocoa shell nanofibers in the production of edible films, coatings, and packaging materials. It recommends their application in cocoa and chocolate products due to the compatibility of smell and color.

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Acknowledgments

The authors would like to thank Banco do Nordeste do Brasil (BNB, Brazil), the Coordination for the Improvement of Higher Education Personne (CAPES, Procad 88881.068456/2014-01), the National Council for Scientific and Technological Development (Productivity in Research Grants 302259/2018-0, 302699/2019-8, CNPq, Brazil), the Research Support Foundation of the State of Minas Gerais (PPM-00458-15, FAPEMIG, Brazil), and the Research Support Foundation of the State of Bahia (FAPESB, Brazil) for their financial support.

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Authors and Affiliations

  1. Pos-Graduation Program in Engineering of Chemical and Biochemical Process, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-900, Brazil

    Ozana Almeida Lessa

  2. Post-Graduation Program in Engineering and Food Science, State University of Southwest Bahia, Itapetinga, 45700-000, Brazil

    Iasnaia Maria de Carvalho Tavares & Lucas Oliveira Souza

  3. Pos-Graduation Program in Polymer Sciences and Technology, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-900, Brazil

    Lucas Galhardo Pimenta Tienne

  4. Department of Forest Science, Federal University of Lavras, Lavras, 37200-900, Brazil

    Matheus Cordazzo Dias & Gustavo Henrique Denzin Tonoli

  5. Department of Food Science, Federal University of Lavras, Lavras, 37200-900, Brazil

    Eduardo Valério de Barros Vilas Boas

  6. Department of Biochemical Engineering, School of Chemistry, Federal University of Rio de Janeiro, Rio de Janeiro, 21949-900, Brazil

    Selma Gomes Ferreira Leite & Melissa Limoeiro Estrada Gutarra

  7. Campus Duque de Caxias, Federal University of Rio de Janeiro, Rio de Janeiro, 25265-970, Brazil

    Melissa Limoeiro Estrada Gutarra

  8. Department of Biotechnology, Faculty of Science, University of Sargodha, Sargodha, 40100, Pakistan

    Muhammad Irfan

  9. School of Life Science and Food Engineering, Huaiyin Institute of Technology, Huaian, 223003, China

    Muhammad Bilal

  10. Department of Exact Sciences and Technology, State University of Santa Cruz, Ilhéus, 45662-900, Brazil

    Marcelo Franco

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  1. Ozana Almeida Lessa
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Lessa, O.A., de Carvalho Tavares, I.M., Souza, L.O. et al. New biodegradable film produced from cocoa shell nanofibrils containing bioactive compounds. J Coat Technol Res 18, 1613–1624 (2021). https://doi.org/10.1007/s11998-021-00519-4

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