Wang Lijuan, Wang Jingjing, Wang Anheng
College of Grain Engineering and Technology, Shenyang Normal University, Shenyang 110034, China.
Department of Chemistry and Biochemistry, School of Mathematics and Physical Sciences (Chemistry), University of Hull, Cottingham Road, Hull HU67RX, UK.
Foods. 2021 Mar 12;10(3):599. doi: 10.3390/foods10030599.
A massive amount of chalaza with nearly 400 metric tons is produced annually as waste in the liquid-egg industry. The present study aimed to look for ways to utilize chalaza as a natural emulsifier for high internal phase emulsions (HIPEs) at the optimal production conditions to expand the utilization of such abundant material. To the author's knowledge, for the first time, we report the usage of hen egg chalaza particles as particulate emulsifiers for Pickering (HIPEs) development. The chalaza particles with partial wettability were fabricated at different pH or ionic strengths by freeze-drying. The surface electricity of the chalaza particles was neutralized when the pH was adjusted to 4, where the chalaza contained a particle size around 1500 nm and held the best capability to stabilize the emulsions. Similarly, the chalaza reaches proper electrical charging (-6 mv) and size (700 nm) after the ionic strength was modified to 0.6 M. Following the characterization of chalaza particles, we successfully generated stable Pickering HIPEs with up to 86% internal phase at proper particle concentrations (0.5-2%). The emulsion contained significant stability against coalescence and flocculation during long term storage due to the electrical hindrance raised by the chalaza particles which absorbed on the oil-water interfaces. Different rheological models were tested on the formed HIPEs, indicating the outstanding stability of such emulsions. Concomitantly, a percolating 3D-network was formed in the Pickering HIPES stabilized by chalaza which provided the emulsions with viscoelastic and self-standing features. Moreover, the current study provides an attractive strategy to convert liquid oils to viscoelastic soft solids without artificial trans fats.
在液蛋行业，每年会产生近400公吨的大量系带，作为废弃物。本研究旨在寻找在最佳生产条件下将系带用作高内相乳液（HIPE）天然乳化剂的方法，以扩大对这种丰富材料的利用。据作者所知，我们首次报道了将鸡蛋系带颗粒用作Pickering（HIPE）乳液制备的颗粒乳化剂。通过冷冻干燥在不同pH值或离子强度下制备具有部分润湿性的系带颗粒。当pH值调至4时，系带颗粒的表面电荷被中和，此时系带颗粒大小约为1500纳米，具有最佳的乳液稳定能力。同样，当离子强度调整为0.6 M时，系带达到合适的电荷（-6 mv）和大小（700纳米）。在对系带颗粒进行表征之后，我们在合适的颗粒浓度（0.5 - 2%）下成功制备出内相高达86%的稳定Pickering HIPE乳液。由于吸附在油水界面的系带颗粒产生的电屏障作用，该乳液在长期储存过程中对聚结和絮凝具有显著的稳定性。对形成的HIPE乳液测试了不同的流变模型，表明此类乳液具有出色的稳定性。同时，在由系带稳定的Pickering HIPE乳液中形成了渗流三维网络，赋予乳液粘弹性和自立特性。此外，本研究提供了一种有吸引力的策略，可将液态油转化为无人工反式脂肪的粘弹性软固体。
