Ethanol production from rice winery waste-rice wine cake by simultaneous saccharification and fermentation without cooking.
Ethanol production by simultaneous saccharification and fermentation (SSF) of low-value rice wine cake (RWC) without cooking was investigated. RWC is the filtered solid waste of fermented rice wine mash and contains 53% of raw starch. RWC slurry was mixed with raw-starch-digesting enzyme of Rhizopus sp. and yeast for SSF. The yeast strain used was selected from 300 strains for RWC fermentation and identified as Saccharomyces cerevisiae KV25. High efficiency (94%) of ethanol production was achieved at optimal condition of uncooked RWC slurry containing 23.03% of starch. The optimal SSF condition determined was 1.125 unit of raw-starch-digesting enzyme per one gram of RWC, 30 degrees C of fermentation temperature, 4.5 of pH slurry, 36 h-age of seeding culture, initial yeast cell 2 x 10(7) per ml slurry, 17 mM urea as nitrogen additive, 0.25 mM Cu(2+) as metal ion additives, 90 h of fermentation time. In this optimal condition, ethanol production by SSF of uncooked RWC slurry was improved to 16.8% (v/v) from 15.1% (v/v) of pre-optimization.
Vu
Van Hanh
VH
Department of Bioscience and Biotechnology, University of Suwon, Hwaseong 445-743, Korea.
Kim
Keun
K
D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D005656:Fungal Proteins / Q000378:metabolism; D007218:Industrial Microbiology / Q000379:methods*; D012275:Oryza / Q000378:metabolism*; D012233:Rhizopus / Q000201:enzymology; D012441:Saccharomyces cerevisiae / Q000737:chemistry / Q000378:metabolism*; D013213:Starch / Q000378:metabolism*; D014866:Waste Products / Q000032:analysis; D014920:Wine / Q000032:analysis / Q000382:microbiology
D003470:Culture Media; D005656:Fungal Proteins; D014866:Waste Products; D000431:Ethanol; D013213:Starch