Growth kinetics of Rhizopus formosa MUCL 28422 on raw cassava flour in solid state fermentation
✍ Scribed by Sonia C Stertz; Carlos R Soccol; Maurice Raimbault; Ashok Pandey; Jose A Rodriguez-Leon
- Publisher
- Wiley (John Wiley & Sons)
- Year
- 1999
- Tongue
- English
- Weight
- 114 KB
- Volume
- 74
- Category
- Article
- ISSN
- 0268-2575
No coin nor oath required. For personal study only.
✦ Synopsis
Solid state fermentations were carried out using a strain of Rhizopus formosa MUCL 28422 for its ability to grow on raw cassava. Optimal substrate composition, as estimated by surface response design experiments, was 10% each of cassava bagasse and soybean ¯our and 80% cassava ¯our. Optimal fermentation conditions were: temperature 32 °C, initial pH and moisture of the substrate 6.5 and 64%, respectively, and inoculum size 10 6 -spores g À1 dry matter. These conditions were employed for studying the kinetics of the biotransformation of cassava ¯our using Oxygen Uptake Rate (OUR) and Carbon dioxide Evolution Rate (CER) during the process. The respiratory quotient was $1, corresponding to an aerobic process in the ®rst 24±26 h. Sporulation started after 26 h of fermentation when the respiratory quotient showed a trend to increase up to $6. Biomass estimation, based on oxygen consumption (Y x/o ) gave a value of 0.531 g biomass g À1 O 2 consumed and the maintenance coef®cient (m) was of the order of 0.068 g O 2 consumed g À1 biomass h À1 . The corresponding value for the speci®c growth rate (m) was 0.16 h À1 .