Dynamic membrane-assisted fermentation of food wastes for enhancing lactic acid production.
A dynamic membrane (DM) module was inserted into a fermentation reactor to separate soluble products from the fermented mixture to increase lactic acid (LA) production from food wastes under acidogenic conditions (uncontrolled pH, pH 4 and 5). With a high total suspended solid content (20-40g/L) in the fermenter, a stable DM could be maintained through regular backwashing. By effectively intercepting suspended solids and lactic acid bacteria (LAB), the fermenter was able to increase microbial activity and largely promote LA yield. Hydrolysis and acidogenesis rates increased with pH, and the highest LA yield (as high as 0.57g/g-TS) was obtained at pH 4. The microbial community analysis showed that the relative abundance of Lactobacillus increased to 96.4% at pH 4, but decreased to 43.3% at pH 5. In addition, the DM could be easily recovered by intercepting larger particles in less than 2h after each cycle of periodic backwashing.
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, China.
Jialing
J
Tang
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, China; Engineering Technology Research Center for Wastewater Treatment and Reuse, Shaanxi Province, China. Electronic address: xcwang@xauat.edu.cn.
Xiaochang C
XC
Wang
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, China.
Yisong
Y
Hu
School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China; Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, Sydney, NSW 2007, Australia.
Huu Hao
HH
Ngo
Department of Civil and Environmental Engineering, Tohoku University, Sendai 9808579, Japan.
Yuyou
Y
Li
D019149:Bioreactors / Q000382:microbiology; D005285:Fermentation; D005502:Food; D019344:Lactic Acid / Q000096:biosynthesis*; D007778:Lactobacillus
D019344:Lactic Acid
Acidogenic fermentation; Dynamic membrane (DM); Food waste; Lactic acid; pH