Use of pervaporation process for the recovery of aroma compounds produced by P. fermentans in sugarcane molasses

Abstract

Natural fruity aroma was produced during submerged fermentation by Pichia fermentans using sugarcane molasses as a cultivation broth. The aroma compounds were recovered from the fermentation by a pervaporation process using a polydimethylsiloxane membrane (Pervap 4060-Sulzer). Isoamyl acetate, a characteristic compound associated with fruity aromas, was the major compound produced. The pervaporation module was fed at three different temperatures to test the best conditions to recover the natural fruity aroma. The total flux (J _T), partial fluxes of each component (J _i), and enrichment factors (β) were determined within the tested ranges. The process was performed at 45 °C, a feed flow of 1.5 mL/min and 0.1 kPa, for a duration of 13 h to concentrate the natural flavor. The pervaporation process can concentrate the isoamyl acetate from fermented broth from 9 to 61.8 mg/L in the first hour of pervaporation. As a single step of downstream operation, pervaporation was efficient for recovering and concentrating the natural fruity aroma. The obtained product was colorless and had a characteristic banana flavor.

Keywords: Aroma; Biosynthesis; Fermentation; Pervaporation; Yeast.