[ Objective] The paper aimed to study effects of extrusion temperature on free gossypol and nutritional components of cottonseed meal. [ Method ] Dif- ferent extrusion temperatures （90, 100, 110, 120 and 130℃ ） wer...[ Objective] The paper aimed to study effects of extrusion temperature on free gossypol and nutritional components of cottonseed meal. [ Method ] Dif- ferent extrusion temperatures （90, 100, 110, 120 and 130℃ ） were designed, and contents of free gossypol and nutritional components in cottonseed meal were de- termined. [ Result] The optimal temperature for extrusion of cottonseed meal was 120℃, the degradation rate of free gossypol no longer increased with the increas- ing temperature when the temperature exceeded 120℃. The nitrogen solvable index （NSI） in cottonseed meal reduced quickly with the increase of extrusion temper- ature, and the contents of crude fiber, available lysine and total lysine in cottonseed meal decreased significantly, but the contents of total amino acids and essential amino acid reached maximums at the extrusion temperature of 120℃. The content of branched-chain amino acids also reached a maximum at 120℃. [ Conclusion] The extrusion temperature of 120℃ was preferred for lowering free gossypol significantly when maintaining higher nutritional value of cottonseed meal. The paper provided a certain technical basis for extrusion processing of cottonseed meal.展开更多
The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fermentation of cottonseed meal (CSM). Six g...The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fermentation of cottonseed meal (CSM). Six groups of disinfected CSM sub- strate were incubated for 48 h after inoculation with either of the fungi C. capsuligena ZD-1, C. tropicalis ZD-3, S. cerevisae ZD-5, A. terricola ZD-6, A. oryzae ZD-7, or A. niger ZD-8. One not inoculated group (substrate) was used as a control. Levels of initial and final free gossypol (FG), crude protein (CP), amino acids (AA) and in vitro digestibility were assayed. The experiment was done in triplicate. The experimental results indicated that microbial fermentation could greatly decrease (P<0.05) FG levels in CSM. The de- toxification efficiency differed between the species of microorganisms applied. From the perspective of reducing CSM potential toxicity, C. tropicalis ZD-3 was most successful followed by S. cerevisae ZD-5 and A. niger ZD-8. They could reduce FG levels of CSM to 29.8, 63.07 and 81.50 mg/kg based on DM (dry matter), respectively, and their detoxification rates were 94.57%, 88.51% and 85.16%, respectively. If crude protein, amino acids content and their in vitro digestibility were also taken into account, A. niger ZD-8 may be the best choice. The CP content of CSM substrate fermented by C. tropicalis ZD-3 and A. niger ZD-8 were improved by 10.76% and 22.24%; the TAA (total amino acids) contents were increased by 7.06% and 11.46%, and the EAA (essential amino acids) were raised by 7.77% and 12.64%, respectively. Especially, the levels of methionine, lysine and threonine were improved greatly (P<0.05). The in vitro CP digestibility of CSM fermented by C. tropicalis ZD-3 and A. niger ZD-8 was improved by 13.42% and 18.22%, the TAA were increased by 17.75% and 22.88%, and the EAA by 16.61% and 21.01%, re- spectively. In addition, the in vitro digestibility of methionine, lysine and threonine was also improved greatly (P<0.05).展开更多
基金Supported by Guide Project of Xinjiang Academy of Agricultural and Reclamation Science(60YYD201308)
文摘[ Objective] The paper aimed to study effects of extrusion temperature on free gossypol and nutritional components of cottonseed meal. [ Method ] Dif- ferent extrusion temperatures （90, 100, 110, 120 and 130℃ ） were designed, and contents of free gossypol and nutritional components in cottonseed meal were de- termined. [ Result] The optimal temperature for extrusion of cottonseed meal was 120℃, the degradation rate of free gossypol no longer increased with the increas- ing temperature when the temperature exceeded 120℃. The nitrogen solvable index （NSI） in cottonseed meal reduced quickly with the increase of extrusion temper- ature, and the contents of crude fiber, available lysine and total lysine in cottonseed meal decreased significantly, but the contents of total amino acids and essential amino acid reached maximums at the extrusion temperature of 120℃. The content of branched-chain amino acids also reached a maximum at 120℃. [ Conclusion] The extrusion temperature of 120℃ was preferred for lowering free gossypol significantly when maintaining higher nutritional value of cottonseed meal. The paper provided a certain technical basis for extrusion processing of cottonseed meal.
基金Project (No. 30471255) supported by the National Natural ScienceFoundation of China
文摘The objective of this work was to investigate the effect of six individual strains of fungi on the reduction of gossypol levels and nutritional value during solid substrate fermentation of cottonseed meal (CSM). Six groups of disinfected CSM sub- strate were incubated for 48 h after inoculation with either of the fungi C. capsuligena ZD-1, C. tropicalis ZD-3, S. cerevisae ZD-5, A. terricola ZD-6, A. oryzae ZD-7, or A. niger ZD-8. One not inoculated group (substrate) was used as a control. Levels of initial and final free gossypol (FG), crude protein (CP), amino acids (AA) and in vitro digestibility were assayed. The experiment was done in triplicate. The experimental results indicated that microbial fermentation could greatly decrease (P<0.05) FG levels in CSM. The de- toxification efficiency differed between the species of microorganisms applied. From the perspective of reducing CSM potential toxicity, C. tropicalis ZD-3 was most successful followed by S. cerevisae ZD-5 and A. niger ZD-8. They could reduce FG levels of CSM to 29.8, 63.07 and 81.50 mg/kg based on DM (dry matter), respectively, and their detoxification rates were 94.57%, 88.51% and 85.16%, respectively. If crude protein, amino acids content and their in vitro digestibility were also taken into account, A. niger ZD-8 may be the best choice. The CP content of CSM substrate fermented by C. tropicalis ZD-3 and A. niger ZD-8 were improved by 10.76% and 22.24%; the TAA (total amino acids) contents were increased by 7.06% and 11.46%, and the EAA (essential amino acids) were raised by 7.77% and 12.64%, respectively. Especially, the levels of methionine, lysine and threonine were improved greatly (P<0.05). The in vitro CP digestibility of CSM fermented by C. tropicalis ZD-3 and A. niger ZD-8 was improved by 13.42% and 18.22%, the TAA were increased by 17.75% and 22.88%, and the EAA by 16.61% and 21.01%, re- spectively. In addition, the in vitro digestibility of methionine, lysine and threonine was also improved greatly (P<0.05).
