物理改性处理对小米水溶性膳食纤维理化性质及结构的影响

利用高温高压、蒸煮、超声三种手段分别对小米水溶性膳食纤维进行物理改性，以探究不同物理改性对小米水溶性膳食纤维的理化性质及结构的影响。结果表明，改性后小米水溶性膳食纤维的化学基团无明显变化，表面出现裂痕，结构疏松多孔，有团聚现象，热稳定性上升，持水力、水膨胀力、持油力、结合脂肪能力均得到提高，其中经超声处理后四种能力提高最为显著（P<0.05），分别提高101.82%，36.67%，63.86%，33.08%；通过测定处理后的水溶性膳食纤维总抗氧化能力，发现经超声处理后的水溶性膳食纤维总抗氧化能力较强（P<0.05）。综上所述，三种物理改性手段均对小米水溶性膳食纤维的理化性质及结构特性具有一定影响，其中经超声处理后的小米水溶性膳食纤维理化性质改善较明显。

Effect of physical modification on physicochemical properties and structure of soluble dietary fiber of millet

Physical modification of soluble dietary fiber of millet was carried out by means of high temperature-high pressure, cooking and ultrasonic treatment, in order to explore the influence of different physical modification on the physical and chemical properties and structure of soluble dietary fiber of millet. The results show that the modified soluble dietary fiber from millet chemical group has no obvious change, surface crack, porous structure, has a reunion phenomenon, thermal stability, hold water, water expansion force, oil force, combined with fat ability are improved, which after ultrasonic treatment four ability to improve the most significant (P < 0.05), respectively increased by 101.82%, 36.67%, 63.86%, 33.08%. By measuring the total antioxidant capacity of water-soluble dietary fiber after ultrasonic treatment, it was found that the total antioxidant capacity of the soluble dietary fiber of millet after ultrasonic treatment was stronger (P<0.05). In conclusion, the three physical modification methods have certain influence on the physical and chemical properties and structural characteristics of soluble dietary fiber of millet, among which the physical and chemical properties of soluble dietary fiber of millet after ultrasonic treatment are significantly improved.