发芽处理对小麦面粉中内源性β-木糖苷酶的影响

摘要

In order to study the effect of the germination wheat flour onβ–xylosidase enzyme and arabinoxylan(AX),germinate wheat flour(including B flour and M flour )as raw material, the contents of AX and theirβ–xylosidase activities were determined respectively,the effects of germinationon dough rheology properties were studied ,and the correlation with flour physicochemical was analyzed. The results showed that with extending the time of wheat germination,the activities ofβ–xylosidase increased first and then decreased;the contents of water extractable arabinoxylan (WE–AX)gradually increased with the increase of the germination period,and the water unextractable arabinoxylan(WU–AX)contents were reduced,while the total AX contents showed a slight downward trend. With the time of germination increasing,the resistance to stretching of dough decreased and B flour below the M flour.β–xylosidase activity,WE–AX content,and extensibility were positively correlated with germination time,while total AX content,WU–AX content,ash content,resistance to stretching had negative correlation(ρ<0.01);dough extensibility was positively correlated withβ–xylosidase activity,and total AX,WU–AX,flour yield,resistance to stretching were significantly negatively correlated(ρ<0.01).%为研究发芽对小麦面粉中β–木糖苷酶及阿拉伯木聚糖（AX）的影响，以发芽小麦的面粉（包括皮磨粉和心磨粉）为原料，测定发芽后β–木糖苷酶和AX的变化，研究面团的流变学特性，及其与面粉理化指标间的相关性。结果表明：小麦发芽的时间越长，β–木糖苷酶的活力呈先升高后降低的趋势；发芽小麦面粉中水溶性阿拉伯木聚糖（WE–AX）随发芽时间的延长含量逐渐升高，水不溶性阿拉伯木聚糖（WU–AX）含量降低，总AX呈现略微下降的趋势；发芽时间越长，面团的拉伸阻力越小，且皮磨粉低于心磨粉；发芽时间与β–木糖苷酶活性、WE–AX含量和延展性呈高度正相关，与总AX含量、WU–AX含量、灰分含量、拉伸阻力具有较好的负相关性；β–木糖苷酶活性与面团延展性高度正相关，与总AX、WU–AX、出粉率、拉伸阻力呈显著负相关（ρ＜0.01）。