Solid-state fermentation process

A solid-state fermentation process for the production of ethanol from apple pomace by Saccharomyces cerevisiae was described by Khosravi and Shojaosadati (2003). A moisture content of 75% (wt/wt), an initial sugar concentration of 26% (wt/wt), and a nitrogen content of 1 % (wt/wt) were the conditions used to obtain 2.5% (wt/wt) ethanol without saccharification and 8% (wt/wt) with saccharification. The results indicate that... 

Adinarayana, K., Ellaiah, P., Srinivasulu, B., Bhavani Devi, R., and Adinarayana, G. (2003b). Response surface methodological approach to optimize the nutritional parameters for neomycin production by Streptomyces marinensis under solid-state fermentation. Process Biochem. 38,1565-1572. 

Stredansky, M. and Conti, E. (1999). Xanthan production by solid state fermentation. Process Biochem. 34, 581-587. 

Kumar, D., Jain, V.K., Shanker, G., and Srivastava, A. 2003. Utilisation of fruits waste for citric acid production by solid state fermentation. Process Biochemistry 38 1725-1729. 

The equipment in the solid-state fermentation process is relatively simple and the capital investment is low. However, new types of fermentor for large-scale cellulase production need to be developed. 

Kim et al. studied the solid-state fermentation processes of T. reesei and Sporotrichum cellulophilum. The optimal water content for growth phase of T. reesei and S. cellulophilum is 57 and 70%, respectively, but is the same as the cellulase production phase (50%) [31]. 

In the solid-state fermentation process, the water activity is variable because of evaporation and metabolism. In order to keep the water activity constant, the humidity of the supplied air should be controlled or a humidifier should be installed in the fermentor. The relationship between the water activity within the solid substrate and the equilibrium relative humidity (ERH) of the surrounding air can be expressed as ... 

Parameters to describe a solid-state fermentation process for cellulase production include physical properties such as temperature, pH, humidity and water activity, particle size, pile and real densities, pore size and porosity, etc. chemical components such as medium composition, gas-phase composition, amount and properties of microorganisms, activities of cellulases, etc. and kinetic para-... 

Figure 3 Industrial scale Solid state fermentation process...

Solid-state fermentation processes involve the same general steps as are involved in SLF, namely upstream processing of substrate and inoculum, fermentation, and downstream processing and waste disposal, although there are differences in how some of the steps are carried out (Fig. 2). A typical process has the following features ... 

Huang SY, Wang HH, Wei CJ, Malaney GW, Tanner RD (1986) Kinetic responses of the koji solid state fermentation process. In Wiseman A (ed) Topics in enzyme and fermentation biotechnology, vol 10. Ellis Horwood, Chichester, p 88... 

Figure 11.8 Membrane as support of the biofilm in a solid-state fermentation process. Adapted from Wang and Chen (2009).

Pandey A. Recent process developments in solid-state fermentation. Process Biochem 1992 27 109-17. 

Gujarath, A.M., Sadaphal, A., and Bathe, G.A, (2015) Multi-objective optimization of solid state fermentation process. Mater. Manuf. Processes, 30, 511-519,... 

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