摘要
研究了单频40 kHz、80 kHz以及双频40 kHz+80 kHz超声处理对红薯淀粉结构和性质的影响。扫描电镜分析表明,超声处理能够使淀粉颗粒表面出现损伤甚至有孔洞出现。红外光谱分析表明,超声作用没有改变淀粉的分子基团,但破坏其结晶结构,使红外结晶指数下降。淀粉-碘复合物吸收光谱分析表明,超声破坏淀粉支链结构和淀粉长链,直链淀粉含量增加。Brabender曲线表明,淀粉经超声处理后黏度降低,双频超声处理后的淀粉峰值黏度比原淀粉降低15.66%。此外,超声处理后淀粉的透明度提高,双频超声处理30 min时,透射比最大,比原淀粉增加5.3%,但是随着超声时间继续增加,透明度呈现减小的趋势。单频40 kHz、80 kHz和双频40 kHz+80 kHz比较,双频超声处理对淀粉的结构和性质影响效果最明显,80 kHz次之,40 kHz影响程度最小。
The treating effects of single frequency ultrasound of 40 kHz, 80 kHz and dual-frequencyultrasound of 40 kHz ＋ 80 kHz on structure and properties of sweet potato starch were investigated. Usingscanning electron microscopy, many dents and holes were found on the surface of starch granules afterultrasonic treatment. FT-IR analysis indicates that above ultrasounds doesn＇t destroy the functional groups ofstarch, but damage its crystal structure. As a result, its crystalline index decreases. The analysis of theadsorption spectra of starch-iodine complex shows that above ultrasounds destroy amylopectin and starch chains,and the amylose content increases. Brabender curves show that the viscosity of starch could be reducedeffectively by ultrasonic treatment, and the peak viscosity of starch treated with dual-frequency ultrasound is15.66% lower than that of the native starch. In addition, the transmittance of the starch increases by ultrasonictreatment. The starch treated by dual-frequency ultrasound for 30 min shows the maximum transmittance, and itis a 5.3% increase as compared with the native starch. However, continuously increasing ultrasonic treatmenttime could lead to the decrease of the transmittance of the starch. Compared to single frequency of 40 kHz and80 kHz, dual-frequency ultrasonic treatment causes the most obvious changes for the structure and properties ofthe starch, 80 kHz is the second, and 40 kHz the smallest.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2014年第2期370-375,共6页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金面上项目(31071608)
国家高技术研究发展计划(863计划)资助(2012AA021505)
天津东丽区科技创新专项基金项目(2010312)
天津科技大学自然科学基金项目(20110104)
关键词
双频超声
红薯淀粉
结构
性质
dual-frequency ultrasound
sweet potato starch
structure
property
