Effects of inulin and cellulose mixtures on three-dimensional printability of tofu-based inks

Tofu-based three-dimensional (3D) food ink mixed with high ratios of amylodextrin shows good printability but an unbalanced nutritional profile. In this study, we explored the feasibility of utilizing soluble dietary fiber (DF) inulin and insoluble DF cellulose as alternatives to amylodextrin to enhance the printability of tofu ink while ensuring energy-providing proportions suitable for maintaining a healthy body. Texture property analysis revealed that the effect of low ratios of cellulose on the hardness (>5% cellulose; >20% inulin), adhesiveness (>5% cellulose; >20% inulin), and gumminess (>10% cellulose; >20% inulin) of the tofu ink surpassed that of inulin. However, 3D printing results showed that inulin minimally affected the number of self-sustainable layers (Nself-sustain), whereas in most cases, 5% cellulose typically did not exhibit any effect and primarily reduced Nself-sustain for filled-square printing. Reduced cohesiveness improved printability for filled-square printing (r = −0.777 and −0.904 for Nself-sustain in cellulose and inulin, respectively), suggesting that the printability can be improved by adding a substance that reduces cohesiveness. At the calculated energy-providing proportions suitable for maintaining a healthy body, inulin effectively supported 3D structure formation, unlike cellulose. These results indicate that cellulose is unsuitable for tofu-based ink, whereas inulin slightly enhances its printability. My results revealed the effects of inulin and cellulose on the textural properties, printability, and energy-providing proportions of tofu ink. This study is expected to promote the development of edible inks with good printability and balanced nutrition for 3D food printing.