Herein, we examined the impact of varying temperatures (20–60 ℃) on the rheological behaviors, moisture migration, and 3D printability of fully gelatinized mung bean starch/soy protein isolate composite inks. As the treatment temperature decreased, both the storage modulus ( G ′) and yield stress ( τ y ) of the inks increased, enhancing the mechanical strength of the extruded filaments. However, this also led to elevated apparent viscosity and minimum flow stress ( τ f ), causing swelling and irregular extrusion patterns, which compromised printing precision. At higher temperatures, the increased mobility of water molecules within the gels facilitated smoother extrusion due to reduced viscosity. Nevertheless, at excessively high temperatures (60 ℃), the extruded filaments exhibited greater spreading, resulting in poor printing resolution. In contrast, gels processed at an optimal temperature of 50 ℃ exhibited the best printability with smooth extruded filaments and high geometric accuracy, thereby enabling the creation of customized shapes via 3D printing. The molecular chain entanglement induced by the short-term starch retrogradation played a significant role in regulating gel properties across different temperatures. Results from this study could provide valuable insights into the temperature-controlled 3D printing of starch-based gels with excellent printing performance.
Zhang et al. (Sat,) studied this question.