Applied Microbiology and Biotechnology

, Volume 68, Issue 5, pp 622–629

Characterization of very high gravity ethanol fermentation of corn mash. Effect of glucoamylase dosage, pre-saccharification and yeast strain

Biotechnological Products and Process Engineering

DOI: 10.1007/s00253-005-1902-9

Cite this article as:
Devantier, R., Pedersen, S. & Olsson, L. Appl Microbiol Biotechnol (2005) 68: 622. doi:10.1007/s00253-005-1902-9

Abstract

Ethanol was produced from very high gravity mashes of dry milled corn (35% w/w total dry matter) under simultaneous saccharification and fermentation conditions. The effects of glucoamylase dosage, pre-saccharification and Saccharomyces cerevisiae strain on the growth characteristics such as the ethanol yield and volumetric and specific productivity were determined. It was shown that higher glucoamylase doses and/or pre-saccharification accelerated the simultaneous saccharification and fermentation process and increased the final ethanol concentration from 106 to 126 g/kg although the maximal specific growth rate was decreased. Ethanol production was not only growth related, as more than half of the total saccharides were consumed and more than half of the ethanol was produced during the stationary phase. Furthermore, a high stress tolerance of the applied yeast strain was found to be crucial for the outcome of the fermentation process, both with regard to residual saccharides and final ethanol concentration. The increased formation of cell mass when a well-suited strain was applied increased the final ethanol concentration, since a more complete fermentation was achieved.

Copyright information

© Springer-Verlag 2005

Authors and Affiliations

  • Rasmus Devantier
    • 1
    • 2
  • Sven Pedersen
    • 1
  • Lisbeth Olsson
    • 2
  1. 1.Starch, Applied Discovery, Research and DevelopmentNovozymes A/SBagsvaerdDenmark
  2. 2.Center for Microbial Biotechnology, BioCentrum-DTUTechnical University of DenmarkKgs LyngbyDenmark