Effect of pH and retention time on volatile fatty acids production during mixed culture fermentation

Ewelina Jankowska; Joanna Chwiałkowska; Mikołaj Stodolny; Piotr Oleskowicz-Popiel

doi:10.1016/j.biortech.2015.04.096

Effect of pH and retention time on volatile fatty acids production during mixed culture fermentation

Bioresour Technol. 2015 Aug:190:274-80. doi: 10.1016/j.biortech.2015.04.096. Epub 2015 Apr 30.

Authors

Ewelina Jankowska¹, Joanna Chwiałkowska¹, Mikołaj Stodolny², Piotr Oleskowicz-Popiel³

Affiliations

¹ Institute of Environmental Engineering, Faculty of Civil and Environmental Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland.
² Department of Kinetics and Catalysis, Faculty of Chemistry, A. Mickiewicz University, Umultowska 89b, 61-614 Poznan, Poland.
³ Institute of Environmental Engineering, Faculty of Civil and Environmental Engineering, Poznan University of Technology, Berdychowo 4, 60-965 Poznan, Poland. Electronic address: piotr.oleskowicz-popiel@put.poznan.pl.

PMID: 25965252
DOI: 10.1016/j.biortech.2015.04.096

Abstract

Mixed culture fermentation consists of stable microbial population hence waste could be potentially used as a substrates. The aim of the work was to investigate the impact of pH and retention time on the anaerobic mixed culture fermentation. Trials at different pH (4-12) in unbuffered systems were conducted for 5, 10 and 15days. The highest VFAs concentration was achieved after 15days at pH 10 (0.62g/gVSadded), promising results were also achieved for pH 11 (0.54g/gVSadded). For pH 4 and short retention time propionic acid was the major product instead of acetic acid. For batches run at 15days (besides pH 6) caproic acid presence was noticed whereas at pH 11 occurrence of succinic was quantified. Significant correlation between operational factors and fermentation's effluents was proved. Throughout changing simple operating parameters one could design process to produce desirable concentration and composition of VFAs.

Keywords: Anaerobic digestion; Mixed culture fermentation; Volatile fatty acids.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Bacteria, Anaerobic / chemistry*
Bacteria, Anaerobic / metabolism*
Bioreactors / microbiology*
Coculture Techniques / methods*
Culture Media / chemistry
Fatty Acids, Volatile / biosynthesis*
Fatty Acids, Volatile / chemistry*
Fatty Acids, Volatile / isolation & purification
Fermentation
Hydrogen-Ion Concentration
Metabolic Clearance Rate
Microbial Consortia / physiology

Substances

Culture Media
Fatty Acids, Volatile