6. On completion of the process the whole fermented substrate comprises the
product in the case of a food or feed, but other products must be leached out
and recovered in downstream processes. After the recovery of products by
leaching, the waste solids must be disposed of.
This review presents our current state of knowledge with respect to biochemical engineering aspects of these various steps of an SSF process. We define a
biochemical engineering approach as a quantitative approach to characterizing
the key phenomena controlling the performance of a process, with the aim of
using this as a tool in process design and control and optimization of operation,
including the scale-up of laboratory and pilot-scale results to commercial scale.
As will become clear in the review, this biochemical engineering approach
has been developed to the greatest degree for the bioreactor step of SSF
processes.
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Fig. 2. The processes involved in a typical SSF process. Note that the general categories of
substrate preparation, inoculum preparation, fermentation, downstream processing, and
waste disposal also occur in SLF. However, the need to handle solids makes SSF more complicated