School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, China.
Food Chem. 2021 Mar 1;339:128064. doi: 10.1016/j.foodchem.2020.128064. Epub 2020 Sep 12.
Ultrasonic degradation has become a fascinating strategy for preparing modified pectin, contributing to the improvement of pectin's functional characteristics. In this study, the impacts of structural and conformational characteristics of original and ultrasound-treated citrus pectins on their functional properties were examined. The results showed that compared with ultrasound-treated pectins, untreated pectin presented higher rheological and gelling properties primarily attributed to its larger weight-average molecular weight (M), degree of methoxylation, amount of neutral sugar side chains, and z-average radius of gyration, as well as the more extended flexible-chain conformation. However, the ultrasound-treated pectins had better emulsifying properties than untreated pectin in an oil-in-water emulsion system. These properties, visually suggested by morphology analysis, including enhanced emulsifying capacity, emulsifying stability, reduced mean droplet size and negatively charged zeta potential. Moreover, the M and chain conformation of untreated and ultrasound-treated pectins played more decisive roles in their functional properties than the others.
超声降解已成为一种引人入胜的策略，用于制备改性果胶，有助于改善果胶的功能特性。在这项研究中，考察了原果胶和超声处理后的柑橘果胶的结构和构象特征对其功能特性的影响。结果表明，与超声处理后的果胶相比，未经处理的果胶表现出更高的流变学和胶凝特性，这主要归因于其更大的重均分子量 (M)、甲氧基化程度、中性糖侧链的数量、Z 均旋转半径以及更伸展的柔性链构象。然而，在油包水乳液体系中，未经处理的果胶的乳化性能优于超声处理后的果胶。这些特性通过形态分析直观地表现出来，包括增强的乳化能力、乳化稳定性、降低的平均粒径和带负电荷的 ζ 电位。此外，未经处理和超声处理的果胶的 M 和链构象在其功能特性中比其他因素起着更决定性的作用。
