Process for the fermentation of fungal strains

A process for fermentation of fungal strains which secrete glucans with a β-1,3-glycosidically linked main chain and side groups β-1,6-glycosidically bonded thereto, in a cascade of tanks comprising at least a first tank (K1, K31) with a first volume (VK1, VK 31) and a second tank (K2, K32) with a second volume (VK2, VK32), comprising:

• a) fermenting the fungal strains in a first aqueous medium (M1, M31) in the first tank (K1, K31) and the volume of the first aqueous medium (VM1, VM31), resulting in a first mixture (S1, S31),
• b) transferring the first mixture (S1, S31) to the second tank (K2, K32), and
• c) fermenting the fungal strains in the first mixture (S1, S31) in a second aqueous medium (M2, M32) in the second tank (K2, K32) and the volume of the second aqueous medium (VM2, VM32), resulting in a second mixture (S2, S32),
• where the proportion of the volume of the first mixture (VM1, VM31) to the volume of the second tank (VK2, VK32) is in the range between ≧0.1% to ≦50% and where the first mixture (S1, S31) in step b) is passed through at least one high-shear mixer, the high-shear mixer (1) has a shearing geometry, such that the entire first mixture (S1, S31) entirely passes through the shearing geometry of the at least one high-shear mixer.