Effect of Extrusion Temperature on Free Gossypol and Nutritional Components of Cottonseed Meal

摘要

[Objective] The paper aimed to study effects of extrusion temperature on free gossypol and nutritional components of cottonseed meal. [Method]Different extrusion temperatures( 90,100,110,120 and 130℃) were designed,and contents of free gossypol and nutritional components in cottonseed meal were determined. [Result]The optimal temperature for extrusion of cottonseed meal was 120℃,the degradation rate of free gossypol no longer increased with the increasing temperature when the temperature exceeded 120℃. The nitrogen solvable index( NSI) in cottonseed meal reduced quickly with the increase of extrusion temperature,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.