Seed train for large scale enzyme production

A process for producing an enzyme or an enzyme composition, the process comprising:

• a) preparing a fungal inoculum comprising fungal cells in an inoculum bioreactor,
• b) transferring the inoculum to a first of three or more production bioreactors, said first production bioreactor being ready for inoculation,
• c) culturing the fungal cells in the first production bioreactor to produce the enzyme or enzyme composition,
• d) emptying a second of the three or more production bioreactors, said second production bioreactor having reached the end of fermentation, and preparing the second production bioreactor for a new production fermentation,
• e) after (b), but before completion of (d), preparing a second fungal inoculum comprising fungal cells in the inoculum bioreactor,
• f) transferring the second inoculum to the second of the three or more production bioreactors, said second production bioreactor being ready for inoculation,
• g) culturing the fungal cells in the second production bioreactor to produce the enzyme or enzyme composition,
• h) emptying a third of the three or more production bioreactors, said third production bioreactor having reached the end of fermentation, and preparing the third production bioreactor for a new production fermentation,
• i) after (f), but before completion of (h), preparing a third fungal inoculum comprising fungal cells in the inoculum bioreactor,
• j) transferring the third inoculum to the third of the three or more production bioreactors, said third production bioreactor being ready for inoculation,
• k) culturing the fungal cells in the third production bioreactor to produce the enzyme or enzyme composition,
• l) emptying the first of the three or more production bioreactors, said first production bioreactor having reached the end of fermentation, and preparing the first production bioreactor for a new production fermentation, and
• m) after (j), but before completion of (l), repeating at least (a), and after completion of (h) repeating at least (b)-(e),
• wherein the first, second and/or third production bioreactor have a gross vessel volume of 20,000 l to 300,000 l, the inoculum bioreactor has a gross vessel volume of 300 l to 15,000 l and the ratio of the gross vessel volume of the inoculum bioreactor to the gross vessel volume of the first production bioreactor is from 2% to 4.5%, and/or the ratio of the gross vessel volume of the inoculum bioreactor to the gross vessel volume of the second production bioreactor is from 2% to 4.5%, and/or the ratio of the gross vessel volume of the inoculum bioreactor to the gross vessel volume of the third production bioreactor is from 2% to 4.5%.