Department of Chemical Engineering, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
Department of Chemical Engineering, Federal University of Rio Grande do Norte, Natal, RN, Brazil.
Carbohydr Polym. 2022 Nov 15;296:119963. doi: 10.1016/j.carbpol.2022.119963. Epub 2022 Aug 6.
The objective of this study was to evaluate the modification of red rice starch by a combination of hydrothermal pretreatments and α-amylase hydrolysis. In vitro digestibility and the morphological, structural, functional, thermal, textural and rheological properties of red rice starch were evaluated. The starch submitted to autoclave (A3) obtained the highest hydrolysis yield (37.66 %) after 300 min. The morphological analysis showed that for the native starch, the granules presented a polyhedral shape and increased in diameter (2.36-394.12 μm) due to hydrothermal pre-treatments. α-Amylase (9 U mg) from Aspergillus oryzae modified the structure of red rice starch, presenting technological properties different from native starch. X-ray diffraction (XDR) were altered after the starch granules were cooked, showing a rupture in the amylose and amylopectin molecules, which justifies the greater absorption capacity of oil and milk. Cohesiveness, adhesiveness and apparent viscosity decreased according to HPT temperature and pressure, as well as α-amylase action.
本研究旨在评估湿热预处理和α-淀粉酶水解联合对红米淀粉的修饰作用。体外消化率以及红米淀粉的形态、结构、功能、热学、质构和流变特性均得到了评估。经过 300 分钟，高压釜处理（A3）的淀粉获得了最高的水解产率（37.66%）。形态分析表明，对于原淀粉，颗粒呈多面体形且由于湿热预处理而直径增大（2.36-394.12μm）。来自米曲霉的α-淀粉酶（9Umg）修饰了红米淀粉的结构，表现出与原淀粉不同的工艺特性。X 射线衍射（XDR）在淀粉颗粒蒸煮后发生变化，表明直链淀粉和支链淀粉分子发生断裂，这解释了其对油和牛奶更大的吸收能力。根据 HPT 温度和压力以及α-淀粉酶的作用，内聚性、粘性和表观粘度降低。
