Investigating the interaction mechanism of native pectin and protein in enhancing 3D printing accuracy of edible flower gels

Edible flowers are valued for their bioactive, nutritional, and aesthetic properties. This study explored the 3D printability of five edible flowers and identified the essential role of their native biopolymers through integrated analyses of composition, functionality, viscoelasticity, and structure. Heat treatment significantly enhanced printing precision in pectin- and protein-rich gels. The most substantial improvement occurred in pectin-rich roselle (59.96 % to 99.81 %) and protein-rich lotus (90.63 % to 96.25 %). Higher printability was linked to biopolymer-network rearrangement via hydrogen and disulfide bonds and electrostatic interactions, which reduced free water and lowered cellulose crystallinity (up to 11.00 %). These changes improved gel network flexibility, increased storage modulus, and improved microstructural regularity, resulting in smoother layer deposition. In contrast, cellulose-rich gels lacking sufficient pectin and protein underwent recrystallization (4.84 %) and densification after heating, reducing viscoelasticity and printability. These findings provide mechanistic insights for optimizing edible-flower gels for 3D food printing.