Dos Santos Thaís Paes Rodrigues, Franco Célia Maria Landi, do Carmo Ezequiel Lopes, Jane Jay-Lin, Leonel Magali
1College of Agronomic Science (FCA), São Paulo State University (UNESP), Botucatu, São Paulo Brazil.
2Center for Tropical Roots and Starches (CERAT), São Paulo State University (UNESP), Botucatu, São Paulo CEP 18610-034 Brazil.
J Food Sci Technol. 2019 Jan;56(1):376-383. doi: 10.1007/s13197-018-3498-y. Epub 2018 Nov 13.
This study aimed to understand the physicochemical characteristics of sweet potato starch following spray-drying and extrusion processes for desirable applications. Spray-dried starch showed formation of agglomerates and decreased in average granular size from 16.5 μm of the native starch granules to 14.1 μm. Spray-drying reduced the percentage crystallinity from 25.3 to 22.6% and showed a slight decrease in the molecular weight of amylopectin from 3.1 to 2.6 × 10 g mol. In addition, changes in the pasting and gelatinization properties, higher final viscosity (454.4 RVU), and less enthalpy change (8.73 J g) were reported after spray-drying. Thus, spray-drying resulted in partially gelatinized starch, which can be selected for making more viscous products. Extruded sweet potato starch displayed an amorphous structure, showed total loss of crystallinity, and significant reduction in molecular weight of amylopectin to 0.41 × 10 g mol, reflecting complete gelatinization of starch granules during extrusion. Extruded starch showed significant changes in pasting properties, including a display cold viscosity (9.4 RVU). Therefore, extruded starch was suitable for products that require quick solubility and a low final viscosity. Thus, the spray-drying and extrusion processes produce sweet potato starches with particular characteristics that can be used for different and potential applications in industries.
本研究旨在了解喷雾干燥和挤压工艺处理后的甘薯淀粉的理化特性，以实现理想的应用。喷雾干燥淀粉呈现出团聚体的形成，平均颗粒尺寸从天然淀粉颗粒的16.5μm降至14.1μm。喷雾干燥使结晶度百分比从25.3%降至22.6%，支链淀粉的分子量略有下降，从3.1×10 g/mol降至2.6×10 g/mol。此外，喷雾干燥后报告了糊化和凝胶化特性的变化，最终粘度较高（454.4 RVU），焓变较小（8.73 J/g）。因此，喷雾干燥产生了部分糊化的淀粉，可用于制作更粘稠的产品。挤压后的甘薯淀粉呈现出无定形结构，结晶度完全丧失，支链淀粉的分子量显著降低至0.41×10 g/mol，这反映了挤压过程中淀粉颗粒的完全糊化。挤压淀粉的糊化特性发生了显著变化，包括呈现出冷粘度（9.4 RVU）。因此，挤压淀粉适用于需要快速溶解和低最终粘度的产品。因此，喷雾干燥和挤压工艺生产出具有特定特性的甘薯淀粉，可用于工业中的不同潜在应用。
