Effect of solvent transfer in agar gels on stress relaxation under large deformation

Investigation on characteristics of 3D printing using Nostoc sphaeroides biomass

BACKGROUND

Gel-like constructs can be produced using an extrusion-based 3D food printing (3D-FP) technique. Nostoc sphaeroides biomass is a natural gel material. Considering its good nutrition and rheological properties, these algae were chosen in this study as supply material (ink) for 3D-FP. With this gel material, the extrusion-based 3D printing system was set as a model, and the printing behavior was investigated. Furthermore, the 3D-FP mechanisms were explained through low-field nuclear magnetic resonance and rheological measurements.

RESULTS

Results indicated that although fresh biomass gel was printable, non-uniformity and instability occurred during printing. Blanched inks showed non-smooth printing behavior, which was associated with a decrease in elasticity and viscosity. Printability was improved by increasing the rehydration time to 24 h when rehydrated powder was used. Increasing the rehydration time increased the water-binding degree. Pre-gelatinized potato starch was added to the mixture at ratios ranging from 1 to 100 g kg^-1 . The best printing outcome was observed at 40 g kg^-1 potato starch.

CONCLUSION

We emphasize that elasticity and viscosity balance is an essential parameter to achieve printability. The strategies adopted in this work provide new insights into the development of personalized food regarding texture and nutritional additive content. © 2018 Society of Chemical Industry.

Fabrication of hydrogel-coated single conical nanochannels exhibiting controllable ion rectification characteristics

Herein, we report novel, interesting hydrogel-composited nanochannel devices with regulatable ion rectification characteristics.