New biodegradable film produced from cocoa shell nanofibrils
Cellulosic nanofibrils from cocoa shells were used 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 plasticiser in the proportions of 0, 1, 3, 5, and 7% (w/w).
Application in cocoa and chocolate products
The use of 3% and 5% glycerol as a plasticiser 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.
The researchers propose the future application of cocoa shell nanofibers in the production of edible films, coatings, and packaging materials and recommend their application in cocoa and chocolate products due to the compatibility of smell and colour.
The study has been published in Journal of Coatings Technology and Research, Volume 18, November 2021.