Discovery, characterization and stability evaluation of self-assembled submicroparticles in chrysanthemum tea infusions

Chrysanthemum tea infusions are famous and nutritious beverages worldwide. The results showed that numerous negatively charged spherical particles of 60–1000 nm in diameter generally existed in all chrysanthemum tea infusions prepared from 9 kinds of chrysanthemums for tea use. Taking Chrysanthemum morifolium ‘Hangbaiju’ tea infusion as an example, crushing, heating and increasing flower-to-water ratio were three strategies to prepare optimal submicroparticles with the smallest mean hydrodynamic diameter as 288.40 nm and polydispersity index as 0.25. The submicroparticles were stable when temperature change, dialysis, centrifugation, storage, pH change (2–9) and ionic strength change were applied but unstable when freeze-thaw, lyophilization, ultrafiltration, concentration and pH change (10) were applied. Polysaccharides and phenolics were dominant components of submicroparticles which were maintained by hydrogen bonds and hydrophobic interactions among polysaccharides and phenolics. This study provided a novel perspective to decipher and control supramolecular aggregation in chrysanthemum tea infusions for rational manufacturing.