Textural and sensory qualities of low-calorie surimi with carrageenan inserted as a protein substitute using coaxial extrusion 3D food printing

This study proposed a method to produce the low-calorie surimi by inserting a protein substitute (PS) solution composed of carrageenan into surimi using coaxial three-dimensional (3D) printing. Carrageenan was selected for its zero-calorie and highly elastic gel-forming properties. To determine the optimal PS insertion conditions, different κ- and ι-carrageenan composition ratios were tested. Although all PS solutions tested formed a gel during the cooling process, rheological properties indicated PS(kC2.5%-iC0.5%) had the highest similarity to surimi. 3D-printed surimi up to 50% replacement ratio of PS showed the higher printing accuracy and post-processing stability, lower cooking loss, and more similar color when compared with 70% replacement ratio of PS. Using 3D printing to insert PS into surimi effectively reflected the salinity of surimi, despite its low-calorie content. This coaxial system could be adapted in addition to fiber inserts or other 3D printed food products requiring the use of independent two materials.