利用聚焦光束反射分析仪(FBRM)分析了玉米淀粉、马铃薯淀粉和木薯淀粉在糊化过程中颗粒总数的变化,实现了淀粉颗粒变化的"动态"监测,并提出用颗粒总数的变化量/颗粒的初始总数来表示糊化度,简化了以往测量糊化度的方法。结果表明:FBRM测得的玉米淀粉颗粒总数呈先增加后减小的趋势,在70℃时下降幅度最大;马铃薯淀粉颗粒总数一直减小,在70℃时下降幅度最大;木薯淀粉颗粒总数也一直减小,但在65℃时下降幅度最大。FBRM测得玉米淀粉在70℃糊化度达到最大值60.05%,马铃薯淀粉在70℃糊化度达到最大值38.83%,木薯淀粉在65℃糊化度达到最大值54.66%;当温度达到75℃时,玉米淀粉,马铃薯淀粉和木薯淀粉总的糊化度分别为93.55%、90.19%和85.85%,它们都没有达到100%。

The change of starch granule during gelatinization was determined by Focus Beam Reflectance Measurement(FBRM),which was an online monitor of the change of starch granule.Besides,a method to determine gelatinization degree by the total number of starch granules was proposed.The method simplifies previous method and provides useful reference model for the research of pasting property of starch.The results showed that: the number of corn starch measured by FBRM was first increased and then decreased,and the number decreased sharply at 70℃;the number of potato starch measured by FBRM showed a steadily decreased,and also had sharpest decline at 70℃;the number of tapioca starch measured by FBRM showed steadily decreasing with the sharpest decline at 65℃.The highest gelatinization degree for corn starch was 60.05% at70℃ and,potato starch was 38.83% at 70℃ and tapioca starch was 54.66% at 65℃;When the temperature reached 75℃,the total gelatinization degree of corn starch,potato starch and tapioca starch came to 93.55%,90.19% and 85.85%,respectively.None of them reached to 100%.