PROCESS FOR HYDRATING YEASTS IN DEHYDRATED FORM

Process for hydrating a yeast in dehydrated form, comprising: preparing a hydration medium comprising yeast extract in aqueous solution, at a concentration between 1 g/L and 50 g/L, preferably between 5 g/L and 20 g/L, more preferably between 8 g/L and 15 g/L; adding a yeast in dehydrated form to said hydration medium at a concentration between 10 g/L and 200 g/L, preferably between 12 g/L and 100 g/L, more preferably between 15 g/L and 50 g/L; said process being carried out at a temperature between 25°C and 40°C, preferably between 30°C and 35°C, for a time between 30 minutes and 8 hours, preferably between 1 hour and 7 hours, more preferably between 1.5 hours and 6.5 hours. The rehydrated yeast thus obtained can be advantageously used in fermentation processes that allow the production of biofuels usable in diesel or aviation engines such as, for example, ethanol, linear or branched alcohols with different molecular weight, or biochemicals such as, for example, ethanol, glycerol, acetic acid esters (for example, ethyl acetate), arabinitol, lactic acid, succinic acid, microbial oils (bio-oils), or propagated yeast, in particular in fermentation processes carried out in the presence of hydrolyzates deriving from lignocellulosic biomass.