Other terms have been used to describe solid-state fermentation and related
processes, such as solid-phase fermentation, solid-state cultivation, solid-substrate
fermentation, and moist solids fermentation. Also, some workers have used the
term solid-state fermentation to describe processes which have significant
amounts of free water. Moo-Young et al. [4] proposed use of the more general term
solid-substrate fermentation to describe any process in which solid particles of
substrate are involved, regardless of the amount of free water. Solid-substrate
fermentations therefore include solid-state fermentations and other processes
with increasing amounts of water: a solid matrix with an aqueous phase leaching
through it, slurries of solid particles, and solids suspended in an aqueous phase.
Solid-state fermentation was documented as long as 1000 years BC in
Chinese Confucius classics, where the use of soy sauce was mentioned [1]. This
art of food production spread out and influenced many other Asian countries,
where it is presently used to produce a variety of foods, beverages, and related
products: chiang, sufu, soy sauce, red rice, tempe, ontjom, tape ketan and tape
ketella, miso, hamanatto, natto, sake, and nata de pina, among others [5].
66
D.A. Mitchell et al.
Fig. 1. Comparison of typical solid-state fermentation (SSF) and submerged liquid fermentation (SLF) systems. A stirred-bed SSF bioreactor of the design of Durand and Chereau [2] is
compared with a typical stirred SLF bioreactor. For each bioreactor an expanded view of the
microscale is also shown, in order to highlight differences between the micro-structure of the
two systems. The relative scales make it clear that mixing is possible on much smaller scales
in SLF than in SSF, since in SSF mixing cannot take place at scales smaller than the particle
size. Note that particle sizes in SSF are commonly larger than 1 mm
processes, such as solid-phase fermentation, solid-state cultivation, solid-substrate
fermentation, and moist solids fermentation. Also, some workers have used the
term solid-state fermentation to describe processes which have significant
amounts of free water. Moo-Young et al. [4] proposed use of the more general term
solid-substrate fermentation to describe any process in which solid particles of
substrate are involved, regardless of the amount of free water. Solid-substrate
fermentations therefore include solid-state fermentations and other processes
with increasing amounts of water: a solid matrix with an aqueous phase leaching
through it, slurries of solid particles, and solids suspended in an aqueous phase.
Solid-state fermentation was documented as long as 1000 years BC in
Chinese Confucius classics, where the use of soy sauce was mentioned [1]. This
art of food production spread out and influenced many other Asian countries,
where it is presently used to produce a variety of foods, beverages, and related
products: chiang, sufu, soy sauce, red rice, tempe, ontjom, tape ketan and tape
ketella, miso, hamanatto, natto, sake, and nata de pina, among others [5].
66
D.A. Mitchell et al.
Fig. 1. Comparison of typical solid-state fermentation (SSF) and submerged liquid fermentation (SLF) systems. A stirred-bed SSF bioreactor of the design of Durand and Chereau [2] is
compared with a typical stirred SLF bioreactor. For each bioreactor an expanded view of the
microscale is also shown, in order to highlight differences between the micro-structure of the
two systems. The relative scales make it clear that mixing is possible on much smaller scales
in SLF than in SSF, since in SSF mixing cannot take place at scales smaller than the particle
size. Note that particle sizes in SSF are commonly larger than 1 mm