Evaluación del mucílago de cacao (theobroma cacao l) para la obtención de etanol de segunda generación

Abstract

This research was carried out in order to evaluate the cocoa mucilage (Theobroma Cacao L) for the production of second generation ethanol through the alcoholic fermentation process, with which it is intended to take advantage of this by-product that is generated in the harvest of the beans of cocoa, since it has fermentative properties. To start the fermentation process, the cocoa mucilage was first collected under aseptic conditions, the physicochemical characteristics of the sample were determined by the respective analyzes such as: pH (potentiometry), ° Brix (refractometry), titratable acidity (acid-base titration), humidity (thermo gravimetric), ash (calcination) and reducing sugar content (3,5-dinitrosalicylic acid). The fermentation process begins when the reducing sugars present in the mucilage are transformed into ethanol and there is the formation of carbon dioxide (CO2), where the pH increased and the fermentation temperature was constant. In this investigation, 4 treatments were carried out, in which two types of fermentation, spontaneous and controlled, were established. To carry out spontaneous fermentation, the cocoa mucilage was placed in an incubator with constant stirring at a temperature of 25 ° C. In the controlled fermentation, the sample was autoclaved first at a temperature of 121 ° C for 15 minutes, in order to eliminate microorganisms that could affect the fermentation process. It was allowed to cool for an hour until reaching a temperature of 30 ° C, to proceed with the inoculation, commercial Saccharomyces cerevisiae yeast (1 g / L) was used, it was fermented under the same conditions as the spontaneous fermentation treatment , using an incubator. The controlled fermentation treatments performed were; pH adjustment, nutrient addition (NH4) 2SO4 and yeast. The fermentation process was 7 days, in which a pH control, quantity of reducing sugars and ethanol concentration were carried out, taking sample every 24 hours.