[关键词]
[摘要]
水分子相态转变会导致淀粉基制品的品质发生劣变,这主要是由水分子相态转变引起淀粉凝胶特性改变所致。而淀粉基食品在冻融处理过程中经常会涉及到水分子的相态转变。本文以花桥板栗淀粉为研究对象,采用SEM、XRD、FT-IR研究了水分子相态转变处理次数对花桥板栗淀粉凝胶的微观结构、晶体特性等方面的影响。结果显示,水分子相态转变使得花桥板栗淀粉凝胶结构发生失水收缩现象。随着相态转变次数增加,凝胶结构中的孔径逐渐变大并发生淀粉分子重排。水分子相态转变对其形成新的晶体结构贡献不大,后者晶体结构大多为CB型。随着相态转变处理次数的增加,结晶度从2.97%增加到了12.78%,相态转变7次后,结晶度下降为5.71%。随着相态转变的增加,羟基(-OH)发生红移;而醇羟基、C-O-C中的C-O发生蓝移且分别在转变3次、4次后峰位不发生偏移,但峰高增加。
[Key word]
[Abstract]
The phase transition of water molecules usually leads to the deteriorated quality of starch-based products, which is largely associated with the change in starch gel properties caused by the phase transition of water molecules. Starch-based foods often undergo the phase transitions of water molecules during freeze-thaw process. In this paper, the effects of the number of water phase transformation treatments on the microstructure and crystal characteristics of Huaqiao chestnut starch gel were studied using SEM, XRD and FT-IR. The results indicated that the phase transition of water molecules resulted in dehydration and shrinking of the starch gel structure of Huaqiao Chestnut. As the number of phase transitions increased, the pore size in the gel structure became bigger and structural rearrangements occurred. The phase transition of water molecules did not contribute to the formation of new crystal structures, mainly of CB type. With the increase of the number of phase transformation treatments, the degree of crystallinity increased from 2.97% to 12.78%. And after 7 cycles of transition phases, the crystallinity decreased to 5.71%. With the increase in numbers of transition phase cycle, a red-shift for hydroxyl groups (-OH) occurred in the FT-IR profiles; while for alcohol hydroxyl and the C-O in the C-O-C, no shifts occurred after 3-4 cycles of phase transitions, but the peak intensities increased.
[中图分类号]
[基金项目]
国家林业和草原局948项目(2015-4-36);湖南省科技创新平台与人才计划项目(2017TP1021);长沙市科技计划项目(kc1704007)