Production of Protein Bars Using a Mixture of Red Lentil Protein and Κ-Carrageenan by 3d Printing: A Prospective Study on the Feasibility of Producing Protein Hydrogels for Athletes

Abstract

This research aimed to characterize the best proportion of red lentil protein (RLP) and κ-Carrageenan (KC) as ink for 3D printing to prepare hydrogel scaffolds for athletes. In this project, the effect of different concentrations of RLP and KC, pH, heating-time on physicochemical and rheological characteristics of cold-set and heat-set hydrogels were evaluated. The result shows that the hydrogels containing the 5%protein-2%gum for the cold-set and 15%protein-1.5%gum for the heat-set sample were the most desirable sample in terms of hardness and water holding capacity. The rheology results showed that the protein samples containing the highest gum concentration in cold-set hydrogels had the highest solidity and elasticity. Microstructural properties of hydrogels showed that by the increase of gum concentration in a constant ratio of protein, less porosity, and larger pore size, and by raising protein concentration in a fixed proportion of gum, smaller pore size and more porosity can be obtained. FTIR spectroscopy and SDS-page results also demonstrated that between RLP and KC, no specific interactions formed. According to the results, the strength and formability of cold-set hydrogels were better than heat-set hydrogels, so the cold gelation method to produce the product with a 3D printer had better results.

Keywords: Red lentil protein, Cold-set hydrogel, 3D-printing