Browsing by Author "Crespo, Carla F."

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    Characterisation and Evaluation of a Novel Feedstock, Manihot Glaziovii, Muell. Arg, for Production of Bioenergy Carriers: Bioethanol and Biogas
    (2014) Moshi, Anselm P.; Crespo, Carla F.; Badshah, Malik; Hosea, Ken M. M.; Mshandete, Anthony M.; Elisante, Emrode; Mattiasson, Bo
    The objective of this study was to characterise and evaluate a wild inedible cassava species, Manihot glaziovii as feedstock for bioenergy production. Tubers obtained from 3 different areas in Tanzania were characterised and evaluated for bioethanol and biogas production. These bioenergy carriers were produced both separately and sequentially and their energy values evaluated based on these two approaches. Composition analysis demonstrated that M. glaziovii is a suitable feedstock for both bioethanol and biogas production. Starch content ranged from 77% to 81%, structural carbohydrates 3–16%, total crude protein ranged from 2% to 8%. Yeast fermentation achieved ethanol concentration of up to 85 g/L at a fermentation efficiency of 89%. The fuel energy of the bioethanol and methane from flour-peels mix ranged from 5 to 13 and 11 to 14 MJ/kg VS, respectively. Co-production of bioethanol and biogas in which the peels were added to the fermentation residue prior to anaerobic digestion produced maximum fuel energy yield of (15–23 MJ/kg VS).
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    High Bioethanol Titre from Manihot Glaziovii through Fed-Batch Simultaneous Saccharification and Fermentation in Automatic Gas Potential Test System
    (Elsevier, 2014) Moshi, Anselm P.; Crespo, Carla F.; Badshah, Malik; Hosea, Ken M.; Mshandete, Anthony M.; Mattiasson, Bo
    A process for the production of high bioethanol titre was established through fed-batch and simultaneous saccharification and fermentation (FB-SSF) of wild, non-edible cassava Manihot glaziovii. FB-SSF allowed fermentation of up to 390 g/L of starch-derived glucose achieving high bioethanol concentration of up to 190 g/L (24% v/v) with yields of around 94% of the theoretical value. The wild cassava M. glaziovii starch is hydrolysable with a low dosage of amylolytic enzymes (0.1–0.15% v/w, Termamyl® and AMG®). The Automatic Gas Potential Test System (AMPTS) was adapted to yeast ethanol fermentation and demonstrated to be an accurate, reliable and flexible device for studying the kinetics of yeast in SSF and FB-SSF. The bioethanol derived stoichiometrically from the CO2 registered in the AMPTS software correlated positively with samples analysed by HPLC (R2 = 0.99).