(473e) Applicability of Legume-Based Protein- and Starch-Rich Ingredients in 3D Food Printing: Correlating Rheological Behavior to Printing Properties

3D food printing is an emerging technology that enables the production of more sustainable, nutritional, and creatively diverse food products. The rheological behavior of food materials directly impacts their extrusion, deposition, and stability during and after 3D printing and post-processing cooking procedures. While legumes offer nutritional benefits and are becoming increasingly popular in plant-based diets, their complex rheological properties due to their diverse particle size distribution, protein/starch ratios, and structure challenge their applications in 3D food printing.

Methods

In this study, yellow pea protein and starch isolates were combined in different ratios (ranging from 1:9 to 9:1 protein to starch) to create model legume mixtures. The goal was to determine the ideal protein-starch mixture and water content for extrusion-based 3D printing, without any additives. The ease of extrusion, shape stability after printing, and the outcome of post-processing cooking steps were assessed and correlated to the rheological characteristics of yellow pea pastes.

Results

All pastes demonstrated shear thinning behavior, including optimally formulated and unsuitable pastes for 3D printing. No specific threshold was observed to distinguish the most effective pastes from those clogging the nozzle or expanding after printing based on their storage and loss modulus. Pastes containing identical amounts of solid and water contents but with higher protein concentration exhibited elevated complex viscosity, indicating the demand for more water in protein-rich compositions to achieve optimal results in 3D printing. Greater height was achieved through 3D printing of protein-rich pastes due to their higher yield stress during stress sweep tests. This accounted for the higher deformation of starch-rich pastes after cooking as the post-processing step. The starch-rich pastes experienced a lower water loss rate, leading to a softer structure upon baking than the pastes enriched with protein.

Significance

This study may provide valuable insights into optimizing paste formulation of legume-based ingredients in 3D printing and achieving desired textural and structural attributes in printed food products.

Acknowledgment

The project was funded through USDA-NIFA-AFRI Grant #2020-67021-31141.