啤酒原料小麦及其麦芽木聚糖含量与木聚糖酶活的研究

Research of the Content of Arabinoxylans and the Xylanase Activities of Wheats and Their Malts

通过间苯三酚-冰醋酸法测定10种小麦及其麦芽的阿拉伯木聚糖含量、DNS法测定其木聚糖酶酶活,反应在间苯三酚-冰醋酸法和DNS法的最适反应条件下进行。结果表明:间苯三酚-冰醋酸法的最适条件是反应液用量10mL、反应20min,冷却后30min内基本稳定(P>0.05)。DNS反应最适条件为反应液用量3mL、反应15min,反应完成后35min内基本稳定(P>0.05)。8、9、10号小麦中碱溶性阿拉伯木聚糖含量最低(P>0.05),分别为0.5811±0.0127%、0.6605±0.0620%和0.6603±0.0301%;9、10号麦芽中碱溶性阿拉伯木聚糖最低(P>0.05),含量分别为0.9746±0.0085%和0.7797±0.0508%。4、8、10号小麦中水溶性阿拉伯木聚糖含量最低(P>0.05),分别为0.5423±0.0645%、0.4681±0.0127%和0.3828±0.0403%;而在麦芽中,7、8号品种最低(P>0.05),含量为0.3362±0.0518%和0.2429±0.0467%。小麦发芽后,大部分品种碱溶性阿拉伯木聚糖含量升高,增大最多的是4、7、8号品种(P>0.05),只有3号品种略微减少;水溶性阿拉伯木聚糖含量都降低。小麦发芽后木聚糖酶酶活均增大,小麦的酶活都在60.00～75.00IU/g之间,而在麦芽中各个品种间的差异不显著(P>0.05),都在100.00～120.00IU/mL之间。

The contents of arabinoxylans of 10 cultivars of wheat and their malts were determined using the method of phloroglucin-glacier acetic acid,and their xylanase activities were determined using the way of DNS under the optimal conditions,respectively.The results show that the optimal determination condition of arabinoxylans was 10mL phloroglucin-glacier acetic acid reagent,react time 20min,and within 30min after cooled the reaction product was stable（P0.05）.Moreover,the optimal determination conditions of xylanase activities were as follows：3mL DNS,react time 15min,and within 35min the reaction product was stable（P0.05）.In addition,the No.8,No.9 and No.10 of wheat had the lowest contents of AEAX,which were 0.5811±0.0127%,0.6605±0.0620% and 0.6603±0.0301%,respectively（P0.05）;the No.9 and No.10 of wheat malts had the lowest content of AEAX,which were 0.9746±0.0085% and 0.7797±0.0508% respectively（P0.05）.For content of WEAX,the No.4,No.8 and No.10 of wheats（P0.05） and the No.7 and No.8 of wheat malts（P0.05） had the lowest,which were 0.5423±0.0645%,0.4681±0.0127%,0.3828±0.0403%,0.3362±0.0518% and 0.2429±0.0467% severally.After germination,the content of AEAX in most wheats was raised except for the No.3,in which the increase of the No.4,No.7 and No.8 was maximum（P0.05）;all the contents of WEAX were declined,and all the activities of xylanase were raised.In the wheats researched,the xylanase activities were between 0.6 and 0.8 IU/mL,and 0.9-1IU/mL after malting（P0.05）.