栖热菌4-α-糖基转移酶对玉米淀粉凝胶特性及抗消化性的影响

Effect of Thermus 4-α-Glucanotransferase on the Gel Properties and Anti-Digestibility of Corn Starch

利用栖热菌4-α-糖基转移酶(TSαGT)处理玉米淀粉,通过质构TPA及酶解分析等方法研究该酶对玉米淀粉糊化、凝胶特性和消化性的影响。结果表明,TSαGT可以显著降低玉米淀粉中直链淀粉含量(从30%降低至10%),从而使淀粉糊冻融稳定性提高、糊透明度改善;在0.03～0.09 U/g酶加量条件下,TSαGT可使玉米凝胶硬度略微降低,而胶着性和咀嚼性提高到原来的1.6倍,黏接性、回复性和弹性也得到小幅提高,同时玉米淀粉的慢消化及抗消化淀粉成分分别提高至原来的1.5和1.9倍。因此,TSαGT可应用于玉米淀粉的优化改性,控制合适的酶处理程度可以显著提高玉米淀粉糊及凝胶的应用特性,同时增加其抗消化性。

The effects of 4 -a -glucanotransferase （TSctGT）from thermus on the corn starch paste, gel properties and digestibility of corn starch were investigated. The results showed that TSaGT can obviously decrease the content of amylose from 30% to 10% in corn starch, and therefore improve the freeze - thaw stability and clarity of corn starch paste ; the instrumental texture profile analysis exhibited that, with 0.03 - 0.09 U/g additional content of the enzyme, both the cohesiveness and chewiness of corn starch gel were improved to 1.6 times, the springiness, gumminess and resilience of starch gel were all have small increase as well as the gel hardness of was slightly decreased. The vitro digestibility test according to Englyst method indicated the content of slowly digestible starch and anti - digestible starch were improved to 1.5 and 1.9 times, respectively. Therefore, TSaGT can be applied into the corn optimization ; controlling proper enzyme treatment can improve the application property of corn starch paste and gel; meanwhile to increase the anti -digestibility.