湿热处理对马铃薯淀粉超高压糊化的影响

Effect of heat moisture treatment on ultra-high pressure induced pasting process of potato starch

中文关键词:  马铃薯淀粉  超高压糊化  湿热处理

英文关键词:potato starch  ultra-high pressure induced pasting  heat moisture treatment

中文摘要:

      目的 研究湿热处理对马铃薯淀粉超高压糊化的影响。方法 将经过不同时间湿热处理的样品进行不同压力的超高压处理, 采用偏光显微、X射线衍射、差示扫描量热、快速粘度分析等技术对马铃薯淀粉样品颗粒形貌、结晶结构、糊化特性热特性进行研究。结果 湿热处理增加了马铃薯淀粉的相对结晶度及糊化焓值, 提升了糊化温度。同时通过改变淀粉颗粒内部结构, 引起淀粉分子吸水性降低, 进而导致淀粉膨胀性变差, 粘度降低, 粘度曲线由A型向D型转变。无论湿热与否, 淀粉在400~600 MPa超高压处理过程中, 其相对结晶度、糊化焓值均降低, 但与原淀粉相比, 湿热处理后淀粉在超高压处理过程中相对结晶度和糊化焓值降低程度减小。结论 马铃薯淀粉水分含量为30%(m:m)时, 90 ℃湿热处理5~15 h导致淀粉颗粒内部结构更为致密, 增加其压力抵抗性, 延缓了超高压糊化过程。

英文摘要:

      Objective To research the effect of heat moisture treatment on the ultra-high pressure induced pasting of potato starch. Methods The samples treated for different heat moisture treatment time were subjected by ultra-high pressure treatment with different pressures. The granular morphology, crystalline structure and thermal characteristics of potato starches were analyzed by polarizing microscope, X-ray diffraction, differential scanning calorimetry and rapid viscosity analysis. Results The relative crystallinity, gelatinization enthalpy and gelatinization temperature of potato starch increased during heat moisture treatment. At the same time, by changing the internal structure of the starch granules, the water absorption of the starch molecules was lowered, which led to the deterioration of the swelling property of the starch, the viscosity was lowered, and the viscosity curve was changed from the A type to the D type. Regardless of damp heat or not, the relative crystallinity and gelatinization enthalpy of starch decreased during the ultra-high pressure treatment of 400?600 MPa. However, compared with the native starch, the degree of reduction in the relative degree of crystallinity and gelatinization enthalpy decreased for the heat moisture treated starches. Conclusion When the moisture content for potato starch is 30% (m:m), the heat moisture treatment at 90 ℃ for the treated time ranged from 5?15 h leads to the denser internal structure of potato starch granules, increases their pressure resistance and delays the ultra-high pressure induced pasting process.