Obtención de etanol de segunda generación a partir de banano deshidratado residual mediante fermentación alcohólica

Abstract

This research work was developed with the aim of obtaining second generation ethanol from the residual dehydrated banana puree through an alcoholic fermentation, and in turn take advantage of these by-products which are discarded without any use. The corresponding tests for the physical-chemical characterization of the residual dehydrated banana were the following: ºBrix by refractometry, Total acidity by acid-base volumetry, Reducing sugars by uv-visible spectrophotometry method, moisture and ash by thermogravimetric method. The by-product of the dehydrated banana puree was obtained from agricultural plants where this type of food is processed before it is discarded, then these wastes go through a grinding and sieving process to obtain small particles. A mixture was made for one liter of product, which used 15% dehydrated banana puree residues and 85% water at a temperature of 75 ° C until the particles dissolved in the water, then the finished mixture was sterilized for 30 minutes at 115 ° C in an autoclave to subsequently cool to a temperature of 28 ° C to add the inoculum of lyophilized Saccharomyces cerevisiae yeast. The fermentation was carried out for 7 days at two temperatures of 25ºC and 30ºC in amber glass bottles of 1 liter with their respective water traps that allows the exit of co2 resulting from alcoholic fermentation. Samples were taken every 24 hours determining pH, ºBrix and reducing sugars. The following percentages were obtained as a result of the chemical physical characterization of the residual dehydrated banana puree: pH 4.85; 20 º Brix, ashes 2.64%; Acidity 0.14%; Humidity 4.09% and reducing sugars 31.08%. The following values were obtained in both treatments of the fermentation phase, treatment 1 to 25 ° a pH of 4.50; 8.18% ethanol and 16.21% reducing sugars. In treatment 2 at 30 ° C a pH of 4.63; 8.49% ethanol and 15.64% reducing sugars. In conclusion, the discarded dehydrated banana puree is an ideal organic compound and a good raw material to be transformed to obtain second generation ethanol for different uses. It was determined and concluded that treatment number 2 is the most efficient for obtaining ethanol, since this treatment reduced more sugar from dehydrated banana puree residues and therefore obtained higher ethanol production, which indicates that the temperature of 30ºC is ideal compared to treatment 1.