Study On The Changes Of Amylase System And Enzyme Activity During Millet Germination

In recent years,with the improvement of people’s living standard,the dietary structure of residents has been paid attention to,and people’s consumption of coarse cereals is increasing.Although millet is rich in nutrients and resources,it is also a barrier to food due to its sensory properties.Some studies have shown that the hydrolysis of millet starch into low molecular sugar can be promoted by changing the germination conditions of millet,thus producing high quality starch syrup products for fermentation industry,so as to promote the long-term development of millet industry.In this study,millet was used as raw material and treated by soaking,germination and drying.The activity of total amylase and the yield of Malt were investigated,the single factor test and response surface test were used to explore the optimum technological conditions for millet germination.Secondly,the effects of drying temperature and time on the activities of Alpha-amylase,-Amylase and limit enzymes were studied.Then two kinds of exogenous materials,Gibberellin and metal ions,were added into millet to explore the effect of exogenous additives on amylase activity.Finally,the quality of Millet Buds was evaluated and the mashing process was optimized.The research not only broadens the edible field of millet,but also provides the high quality syrup made from Millet Malt as the main raw material of fermentation industry.The main findings are as follows:Based on the single factor of soaking time,germinating time and germinating temperature,the response surface test was carried out with amylase activity as the response value,the parameters of germinating conditions of millet were as follows:Soaking Time20min,germinating time 64h,germinating temperature 16°C,amylase activity 218.01 U/g.In the process of Germination,the activity of Alpha-amylase,Amylase and limit of Alpha-amylase were studied.It was found that the activity of the enzyme showed a smooth and then a sharp increase,and the activity of amylase showed a more uniform increase,Amylase has a certain activity at the early stage of Germination.And-amylase activity was much higher than alpha-amylase activity.During the drying process,the activity of Alpha-amylase increased at first and then decreased with the increase of drying time.The activity of amylase decreased obviously with the increase of drying time due to the poor heat resistance.The addition of Gibberellin and metal ions can effectively stimulate the hydrolysis of starch to low molecular sugar.When the concentration of K⁺and Na⁺was 60mg/kg and40mg/kg respectively,the amylase activity reached the highest,when the concentration of Mg²⁺was 30mg/kg,when the concentration of Ca²⁺was 20mg/kg,and when the concentration of Zn²⁺was 20mg/kg,the activity of amylase reached the highest,the optimum addition of Gibberellin was 0.1 mg/kg.The effects of different exogenous materials on the activity of Alpha-amylase were as follows:Ca²⁺>Zn²⁺>Na⁺>K⁺>Mg²⁺.The effects of different exogenous substances on-amylase activity were as follows:Ca²⁺>K⁺>Zn²⁺>Na⁺>Mg²⁺.The effects of different exogenous additives on the activity of ultimate enzymes were as follows:Zn²⁺>Mg²⁺>Na⁺>Ca²⁺>K⁺.The addition of exogenous substance can promote the activity of amylase.The optimum conditions of saccharification were as follows:The ratio of material to water was 1:5,the amount of saccharifying enzyme was 30U/g,and the amount of amylase was 70U/g.Under these conditions,the yield and reducing sugar content of wort were66.89%and 9.85 g/100 m L,respectively.