Bioconversion of food waste to volatile fatty acids: Impact of microbial community, pH and retention time

Kasra Khatami; Merve Atasoy; Maximilian Ludtke; Christian Baresel; Özge Eyice; Zeynep Cetecioglu

doi:10.1016/j.chemosphere.2021.129981

Bioconversion of food waste to volatile fatty acids: Impact of microbial community, pH and retention time

Chemosphere. 2021 Jul:275:129981. doi: 10.1016/j.chemosphere.2021.129981. Epub 2021 Feb 15.

Authors

Kasra Khatami¹, Merve Atasoy², Maximilian Ludtke³, Christian Baresel⁴, Özge Eyice⁵, Zeynep Cetecioglu⁶

Affiliations

¹ Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm, SE100 44, Sweden. Electronic address: kasrakm@kth.se.
² Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm, SE100 44, Sweden. Electronic address: mervea@kth.se.
³ Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm, SE100 44, Sweden; IVL Swedish Environmental Research Institute, Stockholm, Sweden. Electronic address: mmjlu@kth.se.
⁴ IVL Swedish Environmental Research Institute, Stockholm, Sweden. Electronic address: christian.baresel@ivl.se.
⁵ School of Biological and Chemical Sciences, Queen Mary University of London, E1 4NS, UK. Electronic address: o.eyice@qmul.ac.uk.
⁶ Department of Chemical Engineering, KTH Royal Institute of Technology, Stockholm, SE100 44, Sweden. Electronic address: zeynepcg@kth.se.

PMID: 33662716
DOI: 10.1016/j.chemosphere.2021.129981

Abstract

Bio-based production of materials from waste streams is a pivotal aspect in a circular economy. This study aimed to investigate the influence of inoculum (three different sludge taken from anaerobic digestors), pH (5 & 10) and retention time on production of total volatile fatty acids (VFAs), VFA composition as well as the microbial community during anaerobic digestion of food waste. The highest VFA production was ∼22000 ± 1036 mg COD/L and 12927 ± 1029 mg COD/L on day 15 using the inoculum acclimated to food waste at pH 10 and pH 5, respectively. Acetic acid was the dominant VFA in the batch reactors with initial alkaline conditions, whereas both propionic and acetic acids were the dominant products in the acidic condition. Firmicutes, Chloroflexi and Bacteroidetes had the highest relative abundance in the reactors. VFA generation was positively correlated to the relative abundance of Firmicutes.

Keywords: Anaerobic digestion; Food waste; Inoculum; Volatile fatty acids; pH.

MeSH terms

Anaerobiosis
Bioreactors
Fatty Acids, Volatile
Fermentation
Food
Hydrogen-Ion Concentration
Microbiota*
Refuse Disposal*
Sewage

Substances

Fatty Acids, Volatile
Sewage