Optimization of the Process Conditions of Walnut Meal Peptides by Solid State Fermentation-Bacillus subtilis and Aspergillus niger
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
The fermentation performance of Bacillus subtilis (10160) and Aspergillus niger (GIM3.452) using walnut meal as raw materials was investigated. The fermentation conditions of the two strains were optimized to achieve theoptimum fermentation parameters. Firstly, the main factors affecting the yield of peptideswere determined during the solid state fermentation (SSF). The yield of the peptides was applied as an indicator to optimize the SSF conditions for fermentation of Bacillus subtilis and Aspergillus niger, respectively. For Bacillus subtilis,the optimum fermentation time, particle size, ratio of material-to-water, inoculum quantity and fermentation temperature were 3 d, 40 mesh, 1:1.25, 5% and 28 ℃, respectively. The peptide content in the resultant fermented products reached 243.97 mg/g (relative to 50.52 mg/g in raw material). For Aspergillus niger fermentation, the optimum fermentation time, particle size, ratio of material-to-water, inoculum quantity and fermentation temperature were 4 d, 40 mesh, 1:1.25, 15% and 28 ℃, respectively. The peptide content in the last products was 158.61 mg/g. Finally, the higher yield of peptides by Bacillus subtilis fermentation relative to that by Aspergillus niger was verified based on the molecular weight distribution analyses.
