大豆萌发期脂肪氧化酶与脲酶活性变化及钝化方法效果评价

为探究大豆萌发期抗营养因子含量变化规律及钝化方式,以黑龙江地区的黑科56、黑农71为原料,测定此两种萌发大豆在不同萌发时间阶段中脂肪氧化酶和脲酶两种抗营养因子的活性变化,并在萌发20 h酶活性至最低时,分别以烘烤、微波、沸水漂烫3种方法处理萌发豆,比较对脂肪氧化酶与脲酶的钝化效果,筛选出适宜的钝化方式并确定其工艺参数。结果表明,萌发20 h黑科56与黑农71脂肪氧化酶活性分别为100.8 U和99 U,脲酶活性分别为4.73 U/g和4.82 U/g;钝化方式效果最佳为沸水漂烫,其工艺参数为:沸水漂烫40 s,两个品种与未漂烫的大豆相比,脂肪氧化酶活性均降低至10.9 U;脲酶活性分别降低至0.18 U/g(黑科56)和0.13 U/g(黑农71)。通过顶空固相微萃取-气相色谱-质谱联用法对钝化后的两种萌发大豆主要豆腥味物质进行了定性、定量分析,且得出脂肪氧化酶活性与豆腥味物质含量呈极显著正相关。

The Effect Evaluation of Lipoxygenase and Urease Activity and Passivation Method in Soybean Germination

In order to investigate the changes of anti-nutritional factors and the passivation method in soybean germination,Heike 56 and Heinong 71 in Heilongjiang Province were used as raw materials to determine the activity changes of anti-nutritional factors of the lipoxygenase and urease in these two germinated soybeans at different germination time. When the enzyme activity was the lowest at 20 h,the germinated beans were treated separately by baking,microwave and boiling water. The passivation effect of lipoxygenase and urease was compared. Choose the suitable passivation methods and their process parameters. The activity of lipoxygenase of Heike 56 and Heinong 71 were 100.8 U and 99 U,respectively,and the urease activities were 4.73 U/g and4.82 U/g,respectively. The best passivation method was boiling water blanching. The process parameters were boiling water blanching for 40 s,compared with unbleached soybeans,the lipoxygenase activity of both species was reduced to 10.9 U,urease activity was reduced to 0.18 U/g(Heike 56)and 0.13 U/g(Heinong 71).Qualitative and quantitative analysis of bean flavor content from the two main germinated soybean after passivation was carried out by headspace solid phase microextraction(HS-SPME) coupled with gas chromatography-mass spectrometry(GC-MS). It was concluded that the activity of lipoxygenase was significantly positively correlated with the bean flavor substance.