Acquisition, Characterization, and Optimization of Distilled Bioethanol Generated from Fermented Carrot (Daucus carota) Residues

Bioethanol is a liquid biofuel produced from the digestion of biomass and usable waste of organic origin. The objective of this research was to obtain bioethanol from carrot (Daucus carota) residues of the Peruvian Chantenay variety, with a high content of lignocellulosic substances. The in-batch process method of enzymatic hydrolysis, with Aspergillus niger amyloglucosidase, and fermentation, with Saccharomyces cerevisiae yeast, was applied. The ferment was steam distilled and chemically characterized. The process was evaluated by controlling pH and enzyme/yeast mass ratio through the response surface optimization. The optimum conditions for the best values of TSS and % ethanol content for the distilled product were a time of 300 min, yeast/enzyme mass ratio of 24.0, and pH of 4.98. The results showed a significant decrease in sugars in the hydrolysis and fermentation stages, optimum alcohol content in the distilled product of 92.48% (v/v), lower organic compound content, and net calorific value of 23.82 MJ/kg, which is higher than those reported in the literature.

Automated summary

Bioethanol was successfully obtained from carrot residues using a specific enzymatic hydrolysis and fermentation process. The resulting product exhibited superior ethanol content and net calorific value compared to previous studies.