Optimisation of fermentation conditions in the production of ethanol from Palmer mango

Abstract

The objective of this work is to analyse the production potential and optimize the aqueous pulp extract of Palmer mangoes for the production of ethanol. The concentration of total sugars obtained was measured by phenol sulphuric acid method in the pulp and by chromatography; the results showed 83.33 g L-1 and 80.51 g L-1 respectively. By means of preliminary tests at 30°C, it was established that the period of 10 hours presented the biggest yield of ethanol. This was followed by fermentation, with 13 tests and two repetitions in the central point, after which the samples were centrifuged to determine the alcohol content. The optimisation indicated a formula containing 3.0 g L-1 of yeast extract, 8.0 g L-1 of yeast, and 0.35 g L-1 of NH4H2PO4, for an alcohol content of 34.5 g L-1 with a yield of 88.27%.Sugar cane juice, diluted under the same conditions, was also fermented and passed through the same procedures; however the resulting alcohol content of 35.68 g L-1 with a yield of 70.74% proved to be inferior value to that presented when the aqueous extract of Palmer mango was used.

Keywords

• fermentation
• ethyl alcohol
• response surface methodology