不同稳定化处理对青稞籽粒储藏稳定性的影响

Effect of Different Stabilization Treatments on Storage Stability of Highland Barley Grain

为明确不同稳定化处理对青稞籽粒储藏特性的影响,以未处理青稞为对照,通过比较过热蒸汽、远红外和微波3种方式处理的青稞籽粒在储藏过程中脂肪酶活性、脂肪酸值、过氧化值、丙二醛值等的变化,明确不同稳定化处理效果之间的差异,确定稳定化处理青稞的方式。结果表明,过热蒸汽处理条件为温度190℃,时间为70 s;远红外处理条件为面火、底火均为150℃,烘烤40 min;微波处理条件为功率800 W,时间为150 s。在以上条件下青稞籽粒脂肪酶活力下降至较低水平。在加速储藏过程中,对照和稳定化处理后青稞含水量在前30 d内水分含量会逐渐升高,30 d以后水分含量逐渐下降并趋于平衡,脂肪酶的活性、脂肪酸值及菌落总数和霉菌总数均呈升高趋势,且对照青稞脂肪酸值显著上升(P<0.05),并保持较高的脂肪酶活性;对照、远红外和微波处理青稞在储藏过程中的过氧化值不断上升,过热蒸汽处理相对稳定;丙二醛含量在储藏前20 d时并未发生显著变化(P>0.05),对照在20 d后丙二醛含量开始迅速上升。过热蒸汽处理抑制青稞籽粒脂肪酶活性、脂肪氧化及减菌效果相对较好,远红外、微波次之。因此,确定过热蒸汽处理(190℃、70 s)为青稞籽粒稳定化的有效方式。此结果为提高青稞籽粒储藏稳定性提供了参考。

In order to clarify the effects of different stabilization treatments on the storage characteristics of highland barley grains,untreated highland barley was used as the control,compared the changes in lipase activity,fatty acid value,peroxidation value and malondialdehyde value of highland barley grains treated by superheated steam,farinfrared and microwave during storage to clarify the differences in the effects of different stabilization treatments and determine the optimal method for stabilizing highland barley grains.The results showed that when superheated steam treatment condition is 190℃,70 s,the far-infrared treatment conditions were the surface fire and the bottom fire were both 150℃and baked for 40 min,the microwave treatment conditions were 800 W and 150 s.Under this conditions,the lipase activity of highland barley grain decreased to a low level.During accelerated storage,the water content of control and stabilization treatments highland barley gradually increased in the first 30 days,and gradually decreased and tended to be balanced after 30 days,the lipase activity,fatty acid value,total number of colonies and the total number of molds all showed an increasing trend,and the fatty acid value of the control increased significantly(P<0.05),and maintained a high lipase activity.The peroxide value of the control,far infrared,and microwave treated highland barley increased continuously during storage,while the superheated steam treatment remained relatively stable.The malondialdehyde content did not change significantly in the first 20 days(P>0.05),and the malondialdehyde content of control began to increase rapidly after 20 days.The effect of superheated steam treatment on inhibiting lipase activity,fat oxidation and bacteria reduction of highland barley grains was relatively good,followed by far infrared and microwave.Therefore,superheated steam treatment(190℃,70 s)was determined to be an effective way to stabilize highland barley grains.This result provides a reference for improving the storage stability of highland barley grains.