Encapsulating powder ingredients into hydrogel with programmable release ability is highly demanded in many fields including food engineering, medical and healthcare fields. However, directly adding water-insoluble powders into pre-gel solution makes the mixture susceptible to clogging problems during processing, thus limiting the loading rate. To address this problem, a new way to encapsulate water-insoluble powder ingredients without addition of any organic solvent named bubble-assisted encapsulation method is developed in this study. The powders were firstly encapsulated in hydrogel bubbles and further dispersed by T-shaped microfluidic flow to form the core/shell-structured powder in hydrogel microcapsules (P/H microcapsules). The obtained P/H microcapsules had an exceptionally high loading rate of water-insoluble powders up to 94.76%. The P/H microcapsules were freeze-dried for long-term storage, and meanwhile, the as-prepared microcapsules were able to swell rapidly to soft state before use. Moreover, with the well-defined core–shell structure, the P/H microcapsules were endowed with dual release capabilities to external stimuli. The bubble-assisted encapsulation method that enables direct dense encapsulation of powder ingredients at a high loading rate appears promising for water-insoluble food or pharmaceutical ingredients delivery.

在包括食品工程、医疗和保健领域在内的许多领域，都非常需要将粉末成分封装到具有可编程释放能力的水凝胶中。然而，直接将水不溶性粉末添加到预凝胶溶液中会使混合物在加工过程中容易出现堵塞问题，从而限制了加载速率。为了解决这个问题，本研究开发了一种无需添加任何有机溶剂即可封装水不溶性粉末成分的新方法，称为气泡辅助封装方法。粉末首先被包裹在水凝胶气泡中，然后通过 T 形微流体流动进一步分散，形成水凝胶微胶囊（P/H 微胶囊）中的核/壳结构粉末。所得P/H微胶囊的水不溶性粉体负载率高达94.76%。将 P/H 微胶囊冷冻干燥以进行长期储存，同时，所制备的微胶囊在使用前能够迅速膨胀至柔软状态。此外，由于具有明确定义的核壳结构，P/H 微胶囊具有对外部刺激的双重释放能力。气泡辅助封装方法能够以高装载率直接致密封装粉末成分，似乎有望用于水不溶性食品或药物成分的输送。