关键词: 黑曲霉, 固态发酵, 甘薯渣, 营养价值

Abstract: [Objective] This experiment was conducted to investigate the nutritional improvement of sweet potato residue by solid-state fermentation (SSF)using Aspergillus niger and the optimal fermentation parameters were investigated. [Method] Single factor experiment design was adopted to investigate the effects of inoculation size, fermentation time, moisture and temperature on nutritional improvement of sweet potato residue and a orthogonal experiment design was further used to optimize the fermentation parameters described above. [Results] The results showed as following:① Inoculated 1×10⁶ germ per gram fermentation materials with Aspergillus niger strain 3.287, controlled the ratio of substrate vs water ratio to 1:1.3and fermented at 38℃ for 4 days get a best nutritional improvement of sweet potato residue. ② Fermented sweet potato residue under the optimized condition described above and calculated base on dry matter, crude protein was increased from 6.67% to 9.14% (P<0.05);crude fat was increased from 2.71% to 4.75% (P<0.05);the reducing sugar increased from 4.42% to 7.34%. Moreover, the enzyme activity of CMCase, FPA, β-glucosidase and amylase reached to 3.12, 2.45, 2.13 and 3.02 U per gram dry matter, respectively. [Conclusion] The SSF with Aspergillus niger offers an effective alternative to improving the quality of unconventional feed sources such as sweet potato residue.

Key words: Aspergillus niger, solid-state fermentation, sweet potato residue, nutritional value