Effects of acidic treatment, hydroxypropylation, carboxymethylation and heating combined with enzymatic hydrolysis on structural and physicochemical properties of palm kernel expeller dietary fiber (PKEDF) were studied. The carboxymethylation, hydroxypropylation and heating combined with enzymatic hydrolysis effectively improved soluble dietary fiber (SDF) content, water retention capacity (WRC), emulsifying ability index (EAI), water swelling capacity (WSC), viscosity and α-amylase inhibition activity of PKEDF. The carboxymethylation also significantly (p < 0.05) increased emulsion stability index (ESI), but decreased oil retention ability (ORA) and brightness of PKEDF. Besides, the enzymatic hydrolysis with heating significantly enhanced ORA of PKEDF (p < 0.05). In contrast, the acidic treatment decreased the WRC, ORA and EAI of PKEDF. These effects were mainly attributed to the composition and structural modifications as evident from scanning electron microscopy, Fourier-transformed infrared spectroscopy and X-ray diffraction analysis. The changes in physicochemical properties of PKEDF caused by these modification methods can expand its applications in food and other industries.

研究了酸处理，羟丙基化，羧甲基化和加热结合酶促水解对棕榈仁排出机膳食纤维（PKEDF）的结构和理化性质的影响。羧甲基化，羟丙基化和加热结合酶促水解有效地提高了PKEDF的可溶性膳食纤维（SDF）含量，保水能力（WRC），乳化能力指数（EAI），水溶胀能力（WSC），粘度和α-淀粉酶抑制活性。羧甲基化还显着（p  <  0.05）提高了乳液稳定性指数（ESI），但降低了保油能力（ORA）和PKEDF的亮度。此外，加热加热酶解显着提高了PKEDF的ORA（p  < 0.05）。相反，酸性处理降低了PKEDF的WRC，ORA和EAI。从扫描电子显微镜，傅立叶变换红外光谱和X射线衍射分析中可以明显看出，这些影响主要归因于组成和结构修饰。这些修饰方法引起的PKEDF的理化性质变化可以扩展其在食品和其他行业中的应用。