Design and evaluation of an edible coating, functionalized with active compounds, and pectin obtained from the cocoa shell, for technological purposes in the food industry

Abstract

Despite the significant advances in food preservation, the industry faces high economic losses due to decomposition and a decrease in the product's final quality, affecting its texture, taste, smell, nutritional value, and shelf-life characteristics. Using edible films and coatings is a promising alternative to ensure food quality during processing, distribution, and storage. They consist of thin films of biodegradable natural polymers (polysaccharides, proteins, lipids), thus being an environmentally friendly technology that responds to the growing demand by consumers for natural, safe, healthy foods obtained through minimal processing. With the present research project, we sought to design and evaluate an edible coating (RC), using pectin obtained from the waste generated during the harvest and postharvest of two varieties of cocoa (criollo and trinitario), added with corn starch, glycerol, as a plasticizer, and essential oil of cinnamon nano emulsified, as a bioactive ingredient that generated an antioxidant character to the film. For the assembly of the edible coating, a factorial experimental design 2 ^ 2 in triplicate was established to evaluate the effect of the pectin-starch ratio (P / A), and percentage of pectin on the functionality and strength of the film. Finally, with the results, an optimization process was carried out to determine the best conditions for the elaboration of the coating, and under these conditions, the filmogenic solution was developed. The optimized edible film was made with cocoa pectin at a concentration of (1% w / w), and corn starch (1.22% w / w), thus forming the matrix solution added with glycerol (2% w/w) and cinnamon essential oil nano emulsified (0.02% w/w); which was subjected to physicochemical and mechanical quality tests. The results of the ANOVA of the experimental design showed that there was no significant effect of the independent variables %P and (P/A) on the color of the CR, contrary to what happened with the response variables of the antioxidant activity and resistance of the optimized CR.