Anaerobic Solid State Fermentation of Porcine Blood
An anaerobic solid state fermentation (ASSF) of porcine blood by two ferment agents was investigated. The free amino acids (FAA) content was applied as reference indicator, response surface design of Box-Behnken (BBD) was used to select the optimum conditions of ASSF of porcine blood. The optimum conditions were determined as porcine blood moisture of 76.0%, fermentation time of 7d, fermentation temperature of 39.0±0.5 oC, addition of the components of the mixture as follows: wheat bran 10.8 g , corn flour 1.2 g, Active 99 ferment agent I 0.768 g, Active 99 ferment agent II 0.19 g, porcine blood 86.0 g, resulting in FAA content of 23.8 mg/g. Evaluation experiments revealed that FAA content of 22.9 mg/g, which was 96.2% of the predicted value using Eq.2, and achieved a 14-fold increase comparing with the 1.5 mg/g which is the FAA content of unfermented mixture. It was confirmed that the protein of porcine blood was degraded into small peptides by Sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE).