摘要
本文利用扫描电镜、紫外光谱、粒度分析仪等分析手段研究果胶浓度、干热温度和干热时间对甘薯淀粉分子结构的影响。结果表明:经过不同时间干热处理,淀粉与果胶共混的颗粒随着时间的延长而形成小团块且逐渐增多、变大;甘薯淀粉与果胶共混干热后,添加不同浓度果胶的淀粉分子链间的聚合度减小(由未添加果胶的620~626 nm降低到浓度为0.05%的603~608 nm),随着温度的增加和时间的延长可使淀粉分子间的聚合度增大,紫外光谱的最大吸收波长均发生蓝移现象;淀粉颗粒中位径、大颗粒体积分数随着果胶浓度、温度、时间的增加而增大,在干热时间为3 h时淀粉颗粒的中位径最大(为15.47μm),大颗粒体积分数最大可达到6.27%,比在1 h时的大颗粒体积分数高出1.81%;淀粉与果胶共混物的直链淀粉的溶出量随着果胶浓度(0.01%~0.04%)、干热温度和干热时间(1~4 h)的增加而得到更好的抑制。果胶协同干热处理对开发新型甘薯变性淀粉具有重要意义。
The effects of pectin concentration, dry-heat temperature and dry-heat time on the molecular structure of sweet potato starch were studied by electron microscopy, ultraviolet-visible spectroscopy and particle size analyzer.The results showed that the granules blended with starch and pectin formed a small clump with the extension of time, and became bigger after heat treatment at different time.The degree of polymerization between starch and pectin was decreased with the increase of pectin concentration（from 620-626 nm without adding to 603-608 nm with pectin concentration of 0.05% ）, and the degree of polymerization between starch chains weakened with the increase of temperature and time, the maximum absorption wavelength of UV spectrum showed a blue shift.The particle size （ D50 ） and the volume fraction of big starch particles of starch granules increased with the increase of pectin concentration, temperature and time.The particle size （D50） of starch granules was the largest at dry-heat time of 3 h（ 15.47 μm）, and the volume fraction of big starch particles could reach 6.27%, which was 1.81% higher than that at 1 h.The declined leakage of amylose was better inhibited by the increase of pectin concentration （0.01%-0.04% ）, dry-heat temperature and time（ 1-4 h）. Dry-heat treatment is a new method of physical modification of starch, which is of great signifieanee to improve sweet potato starch utilization rate and develop new type modified starch.
出处
《食品工业科技》
CAS
CSCD
北大核心
2017年第9期60-65,共6页
Science and Technology of Food Industry
基金
河南科技学院自然科学重大培育项目(2013ZD04)
河南省科技攻关计划(172102110164)
关键词
甘薯淀粉
果胶
干热处理
淀粉分子结构
sweet potato starch
pectin
dry heating treatment
starch molecular structure
