0000000000804824
AUTHOR
P. Gervais
High pressure inactivation of Escherichia coli and its giant spheroplast at subzero temperature
International audience
Water relations of solid state fermentation
International audience; The hydration level of the culture medium affects drastically the physiology of microorganisms. Thermodynamic properties of water in a solid-state medium such as water potential or water activity, and dynamic properties of water such as water diffusion are examined. The mechanisms of water transfer between intra and extracellular media are discussed, and different results on the incidence of the water activity level on the survival, growth and metabolism of microorganisms are reported. Optimal macroscopic and microscopic growth, or metabolic production by fungi occurs in media with water activity values lower than those of classical cultivation media (≈ 1). In solid …
Solid-State Fermentations of the Genus Aspergillus
For the majority of filamentous fungal species, solid-state media are the natural life media. Growth can occur on the surface or within the whole substrate, depending on the porosity. Industrial solid-state fermentations have been developed largely in traditional food industries such as cheese, Oriental fermentations, fermented vegetables, meat, and other products, and in modern biotechnological industries such as antibiotics and enzymes. At the industrial scale, the latter fermentations allow for a decrease in the drying costs of the final products.