Submerged vs. Solid‐State Conversion of Soybean Meal into a High Protein Feed Using Aureobasidium pullulans

Abstract The goal of this study was to assess the performance of Aureobasidium pullulans in converting soybean meal (SBM) into high protein feed using the submerged and solid‐state processes. High solid loading rates (SLR) were evaluated for each process, i.e., 10–25% for submerged and 35–70% for static solid‐state fermentation. During the submerged fermentation, 10% SLR was considered the best performer due to the high amount of cell density, low residual carbohydrates, and high protein titers, while 40% SLR resulted in the high protein yields and low residual carbohydrates during the static solid‐state fermentation. The solid‐state fermentation was conducted in a 14‐L paddle‐type reactor at 50% SLR, and periodic mixing resulted in a protein titer of ~58% at 72 hours of fermentation. Overall, results showed the feasibility of scaling up these processes in converting SBM to a high protein feed ingredient for animal diet.