OXYGEN TRANSFER IN SOLID-STATE CULTIVATION OF ASPERGILLUS NIGER-TRICHODERMA REESEI CONSORTIUM FOR CITRIC ACID PRODUCTION

The process known as "solid-state cultivation" (SSC) refers to microbial growth on solid supports under limited water conditions. Citric acid is an aerobic bioproduct with several industrial applications, and its production is traditionally microbial. The present work evaluated the oxygen transfer in citric acid production by fungal consortium (Aspergillus niger and Trichoderma reesei) from SSC with sugarcane bagasse with vinasse. Experiments were set up in packed-bed column bioreactor and the results indicate that the highest citric acid in 24 hours at 300 mm bed height, with glucose lead in the solid medium at first 48 hours. Oxygen transfer indicates rates depending of particle bed height, with a kLa profile dependent only on the liquid film thickness controlled by the solid medium moisture.