Department of Food Science and Technology, Shahreza Branch, Islamic Azad University, Shahreza, Iran.
Department of Food Science and Technology, Najafabad Branch, Islamic Azad University, Najafabad, Iran.
Int J Biol Macromol. 2024 Sep;276(Pt 2):133992. doi: 10.1016/j.ijbiomac.2024.133992. Epub 2024 Jul 18.
In this study, the effect of hydrothermal process, ultrasound and combined freezing-ultrasound process on the physical and structural characteristics of wheat starch (Triticum aestivum) was investigated. Two heat-moisture treatments for 2 h (HMT2) and 4 h (HMT4), high-intensity, high-frequency ultrasound under two treatment times (10 to 20 min) (UT10 and UT20) as pre-treatment and sonication after freezing as post-treatment (FUT) on wheat starch suspension was applied. The modifications of starch crystallinity, chemical bonds of starch treated, morphology, thermal, swelling, pasting, and physicochemical characteristics were evaluated. Finally, the starches treated under these conditions were used as ink for a 3D printer, and the characteristics of the printed product were evaluated. The results demonstrate that heat-moisture modified starch increased swelling and size of granules and lowered syneresis values. Sonication promoted molecular depolymerization and reduction of starch swelling and crystallinity. Combined treatment (Sonication and freezing) showed higher peak apparent viscosity during gelatinization and pasting, and the FUT starch-based hydrogels showed the best printability (better ability to stack layers on top of each other and build the desired 3D shape), indicating better reproducibility of this ink. These results showed that FUT is a suitable process for improving the synergy and properties of wheat starch-based hydrogels, which are suitable as inks for use in 3D printers.
本研究考察了湿热处理、超声和冷冻-超声联合处理对小麦淀粉（Triticum aestivum）物理和结构特性的影响。采用 2 小时（HMT2）和 4 小时（HMT4）的两种热湿处理、两种处理时间（10-20 分钟）的高强度高频超声（UT10 和 UT20）作为预处理，以及冷冻后进行超声处理（FUT）对小麦淀粉悬浮液进行处理。评估了淀粉结晶度、淀粉处理的化学键、形态、热学、溶胀、糊化和物理化学特性的变化。最后，将这些条件下处理的淀粉用作 3D 打印机的墨水，并评估打印产品的特性。结果表明，湿热改性淀粉增加了颗粒的溶胀和粒径，并降低了脱水收缩值。超声处理促进了分子的解聚，并降低了淀粉的溶胀和结晶度。联合处理（超声和冷冻）在凝胶化和糊化过程中表现出更高的峰值表观黏度，基于 FUT 淀粉的水凝胶表现出最好的打印性能（更好地堆叠层并构建所需的 3D 形状的能力），表明这种墨水具有更好的可重复性。这些结果表明，FUT 是一种改善小麦淀粉基水凝胶协同作用和性能的合适方法，可作为 3D 打印机用墨水。
