Study on the colloidal and emulsifying properties of different whole-component plant-based particles

In this work, nine different plant materials (lettuce, broccoli, shepherd's purse, orange peel, tangerine peel, lemon peel, lotus root, yam, and ginkgo nut) were used to prepare whole-component colloidal particles through the media milling. The colloidal properties and applicability in forming and stabilizing Pickering emulsions were investigated. The results showed that some particles exhibited good interfacial wettability. These particles could spontaneously absorb at the oil-water interface and effectively decrease interfacial tension. Pickering emulsions stabilized by broccoli colloidal particles exhibited better homogeneity and exceptional stability. While others were unstable to creaming/sedimentation. After slight stratification, the Pickering emulsions stabilized by fruit peel colloidal particles formed a solid gel unexpectedly. The Pickering emulsions stabilized by starch-based colloidal particles were rapidly stratified and coalesced during storage. Colloidal particles prepared from green vegetables and fruit peels demonstrated superior emulsifying capabilities than starch-based colloidal particles. This study indicates that broccoli can be a renewable source of whole-component plant-based stabilizers. It will provide valuable information for the exploitation of natural particle stabilizers and expand the application of plant resources in the food industry.