Customization of liquid-core sodium alginate beads by molecular engineering

Detailed alginate molecular structural factors that modulated the texture of liquid core alginate beads were investigated. Under the same CaCl2 concentration and contacting time, a higher bursting force can be generated from both high Mw and low M/G alginate beads. G-block took part in faster dimerization, producing a compact gel network and long chains providing an elastic response generated by interchain interaction. Within same bursting force, high Mw beads were elastic than high G ones. Shorter chain length and higher M residue allowed more water to trap in the gel network, causing accretion in thickness and downed gel strength. The lowest shell thickness (0.11 +/- 0.01mm) was measured from the highest Mw and M/G sample, while the thickest (0.78 +/- 0.08mm) was from the lowest Mw and M/G alginate. The beads became brittle with a shortened chain length. Thus, alginate-based food products with a desired textural profile can be designed by varying alginate structures.

Automated summary

This study investigated the detailed molecular structural factors that modulate the texture of liquid core alginate beads. It was found that both high molecular weight and low M/G ratio alginate beads generate higher bursting force. The G-block plays a role in faster dimerization, resulting in a compact gel network and long chains that provide elastic response through interchain interaction. Alginate structures can be varied to design alginate-based food products with desired textural profiles.