摘要
对琼胶与β-环糊精复配物的干热改性工艺进行了研究。利用粒度分析仪、流变仪、差示扫描量热计(DSC)、X-射线衍射仪、红外光谱等探究了干热处理不同时间对琼胶与β-环糊精复配物理化性质变化的影响,并分析了干热反应引起的结构变化。结果表明,经过干热处理后,琼胶与β-环糊精复配物的凝胶强度、熔点、透明度、稳态剪切黏度及颗粒粒径均降低,色泽增加,且干热时间越长变化越明显。对临界剪切速率值的分析表明干热处理打断了分子链,使分子链变短、刚性变大。热分析表明,干热处理后复配物的相变吸热焓降低,结晶结构破坏,同时X-射线衍射图也表明了这一特征。红外结果表明,干热后在3000~3800 cm-1处的红外特征峰向高波长移动,分子间的氢键作用力减小。因此,通过复配和干热改性,可改变琼胶的理化性质,特别是制备低熔点且具有合适凝胶强度的产品,满足其在食品工业中不同应用的需求。
The dry-heating treatment of agar/β-cyclodextrin mixture was studied.The effect of different dry-heating time on physicochemical properties of agar/β-cyclodextrin mixture and the changes of structures caused by dry-heating treatment were investigated by dynamic light scattering,rheometer,differential scanning calorimeter,X-ray diffraction and fourier transform infrared.The results showed that the gel strength,melting point,transparency,steady shear viscosity and particle size of agar/β-cyclodextrin mixture decreased and the yellow color of the mixture increased after dry-heating treatment.With the increasing of dry-heating time,these changes were more obvious.The analysis of critical shear rate indicated that dry-heating treatment broke the molecular chains and made the chains short and rigid. Thermal analysis showed that the transformation enthalpy of agar/β-cyclodextrin mixture decreased and the crystal structure damaged after dry-heating treatment. While the X-ray diffraction pattern also showed this characteristic. Fourier transform infrared spectra exhibited that the peaks around 3000 -3800 cm-1 of all samples shifted to higher wavelengths,which indicated that hydrogen bonds between molecules weakened after dry-heating treatment.Thus,dry-heating treatment can change the physicochemical properties of agar,especially can produce agar of low melting point and suitable gel strength,thus to satisfy different applications in the food industry.
作者
李煜
付晓婷
许加超
高昕
LI Yu, FU Xiao-ting, XU Jia-chao, GAO Xin(College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China)
出处
《食品工业科技》
CAS
CSCD
北大核心
2018年第19期34-39,共6页
Science and Technology of Food Industry
基金
国家海洋局海洋公益项目(201405040)
江苏省重点研发计划项目(BE2015335)
关键词
琼胶
Β-环糊精
复配物
干热处理
理化性质
agar
β- cyelodextrin
mixture
dry- heating treatment
physicochemical properties
