本试验旨在研制一种低瘤胃降解率和高瘤胃后释放率的过瘤胃γ-氨基丁酸（γ-aminobutyric acid，GABA）。采用L9(34)正交设计，以GABA含量、包被材料和压力为变量，筛选出保护率较高的样品，分别采用半体内法和体外法测定其瘤胃降解率和瘤胃后释放率。结果显示，固体棕榈油脂作为单一被材比混合被材具有更好的过瘤胃保护效果。当GABA含量50%、用固体棕榈油脂包被、压力11 kPa下制得的样品瘤胃降解率显著低于其他样品，总利用率75.8%；GABA含量50%、固体棕榈油脂与单硬脂酸甘油酯等质量混合物包被、压力9 kPa下制得的样品其瘤胃后释放率最高。利用固体棕榈油脂包被在适宜条件下可调制瘤胃降解率低、瘤胃后释放率高的过瘤胃保护GABA。

The study was conducted to develop a rumen protected γ-aminobutyric acid (GABA) with low ruminal degradability and high post-ruminal dissolution. GABA content, coating material and pressure were used as variables in a L9(34) orthogonal design to select samples with high insoluble rate, then ruminal degradability and post-ruminal dissolution were determined. The results showed as follows: as coating material, solid palm oil product was superior to the mixture of solid palm oil and glyceryl monostearate. The sample produced under the condition of 50% GABA, encapsulated with solid palm oil and under the pressure of 11 kPa was degraded at least in rumen. Its utilization efficiency was 75.8%. The sample produced under the conditions of GABA content of 50%, encapsulated with solid palm oil and glyceryl monostearate equal mass mixture and under the pressure of pressure 9 kPa presented the highest post-ruminal dissolution rate. It is suggested that the solid palm oil can be used as coating material to produced rumen protected GABA with low ruminal degradability and high post-ruminal dissolution.［Chinese Journal of Animal Nutrition, 2010，22（5）:1451-1456］