Bed moisture estimation by monitoring of air stream temperature rise in packed-bed solid-state fermentation

We develop a method for predicting the moisture content of the fermenting solids in an intermittently mixed packed-bed bioreactor on the basis of measurements of the inlet and outlet gas stream temperatures and the assumption that both the gas streams are saturated with water vapor. This method can be used to estimate when an intermittently mixed packed bed should be mixed and how much water should be added during the mixing event. The predictions were experimentally verified for the growth of Aspergillus niger on wheat bran in a thin packed bed. We show that the application of a controller based on our estimation method would have led to adequate moisture control, with significant errors in moisture content prediction only occurring after the last mixing and water-addition event. Our method therefore represents a simple and practical method that can be incorporated into control schemes for intermittently mixed solid-state fermentation bioreactors with forced aeration.

[1]  Arnold L. Demain,et al.  Manual of Industrial Microbiology and Biotechnology , 1986 .

[2]  W. Knol,et al.  Solid-state fermentation of wheat bran by Trichoderma reesei QM9414: substrate composition changes, C balance, enzyme production, growth and kinetics , 1996, Applied Microbiology and Biotechnology.

[3]  A. Rinzema,et al.  Modelling fungal solid-state fermentation: the role of inactivation kinetics , 1999 .

[4]  W. Knol,et al.  The influence of temperature on kinetics in solid-state fermentation , 1998 .

[5]  J Tramper,et al.  A simplified material and energy balance approach for process development and scale-up of Coniothyrium minitans conidia production by solid-state cultivation in a packed-bed reactor. , 1999, Biotechnology and bioengineering.

[6]  Johannes Tramper,et al.  Validation of a model for process development and scale-up of packed-bed solid-state bioreactors. , 2002, Biotechnology and bioengineering.

[7]  J Tramper,et al.  Temperature control in a continuously mixed bioreactor for solid-state fermentation. , 2001, Biotechnology and bioengineering.

[8]  N. Krieger,et al.  Group II Bioreactors: Forcefully-Aerated Bioreactors Without Mixing , 2006 .

[9]  B. K. Lonsane,et al.  Zymotis, a large scale solid state fermenter design and evaluation , 1993 .

[10]  Véronique Bellon-Maurel,et al.  Sensors and measurements in solid state fermentation : a review , 2003 .

[11]  E Latrille,et al.  Indirect measurement of water content in an aseptic solid substrate cultivation pilot-scale bioreactor. , 2001, Biotechnology and bioengineering.

[12]  Shrikumar Suryanarayan,et al.  Current industrial practice in solid state fermentations for secondary metabolite production: the Biocon India experience , 2003 .

[13]  N. Krieger,et al.  A mathematical model describing the effect of temperature variations on the kinetics of microbial growth in solid-state culture , 2005 .

[14]  D. Mitchell,et al.  Response of Rhizopus oligosporus to temporal temperature profiles in a model solid-state fermentation system. , 1999, Biotechnology and bioengineering.

[15]  D. Mitchell,et al.  Estimation of Transfer Coefficients for SSF Bioreactors , 2006 .

[16]  G. Viniegra-González,et al.  Heat transfer simulation in solid substrate fermentation , 1990, Biotechnology and bioengineering.

[17]  N. Krieger,et al.  Biochemical engineering aspects of solid state bioprocessing. , 2000, Advances in biochemical engineering/biotechnology.

[18]  D. Mitchell,et al.  A two-phase model for water and heat transfer within an intermittently-mixed solid-state fermentation bioreactor with forced aeration. , 2002, Biotechnology and bioengineering.

[19]  D. Mitchell,et al.  Mathematical modeling as a tool to investigate the design and operation of the zymotis packed-bed bioreactor for solid-state fermentation. , 2000, Biotechnology and bioengineering.

[20]  N. Krieger,et al.  Recent developments in modeling of solid-state fermentation: heat and mass transfer in bioreactors , 2003 .

[21]  D. Mitchell,et al.  Validation of a model describing two-dimensional heat transfer during solid-state fermentation in packed bed bioreactors. , 1998, Biotechnology and bioengineering.

[22]  J. Lenz,et al.  A survey of computational and physical methods applied to solid-state fermentation , 2004, Applied Microbiology and Biotechnology.

[23]  C L Cooney,et al.  Measurement of heat evolution and correlation with oxygen consumption during microbial growth , 1969, Biotechnology and bioengineering.

[24]  M. Schutyser Mixed Solid-State Fermentation. Numerical modeling and experimental validation , 2003 .

[25]  David A. Mitchell,et al.  New developments in solid-state fermentation , 2000 .

[26]  Sergio Revah,et al.  Heat transfer in citric acid production by solid state fermentation , 1996 .