Modified Tartary buckwheat (Fagopyrum tataricum Gaertn.) starch by gaseous ozone: Structural, physicochemical and in vitro digestible properties
Modified Tartary buckwheat (Fagopyrum tataricum Gaertn.) starch by gaseous ozone: Structural, physicochemical and in vitro digestible properties
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DOI：
10.1016/j.foodhyd.2021.107365
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发表时间：
2021-12-27
影响因子：
10.7
通讯作者：
Xing, Yanan
中科院分区：
文献类型：
--
作者：
Hu, Jingwei;Li, Xiaoping;Xing, Yanan
本研究调查了气态臭氧处理对苦荞淀粉（TBS）的结构、理化和体外消化特性的影响。结果表明，臭氧处理增加了可检测的羰基和羧基含量，提高了直链淀粉含量，并降低了TBS的pH值。通过SEM、CLSM和小角X射线散射（SAXS）对天然TBS和臭氧处理TBS（OTBS）的颗粒微观结构进行表征，结果表明OTBS颗粒光滑度和完整性降低，FITC荧光着色区域减少，结晶层减少，非晶区增加。 FTIR和XRD结果表明，适当的臭氧处理时间（2.5和7.5分钟）由于增加了分子间氧化交联而增强了短程和长程有序结构，而过度处理（15和20分钟）会导致淀粉降解。随着处理时间的增加，表观粘度增加，而击穿粘度、消退粘度、溶胀力和溶解度降低。 OTBS 表现出更高的糊化焓 (Delta H) 和凝胶化后更好的粘弹性（6% OTBS 凝胶，w/w）。此外，OTBS-2.5和OTBS-7.5表现出快速消化淀粉（RDS）含量下降和抗性淀粉（RS）含量增加，表明两种氧化淀粉的可消化特性下降，这为开发TBS作为新的变性淀粉源提供了可行的途径。
The present study investigated the effects of gaseous ozone treatment on the structural, physicochemical and in vitro digestible properties of Tartary buckwheat starch (TBS). The results showed that gaseous ozone treatment increased the detectable carbonyl and carboxyl groups content, improved the amylose content, and decreased pH of TBS. The granule microstructures of native TBS and ozone-treated TBS (OTBS) were characterized by SEM, CLSM and small-angle X-ray scattering (SAXS), showing that OTBS exhibited a reduced granule smoothness and integrity, lessened coloration area of FITC fluorescent as well as decreased crystalline layer and increased amorphous region. FTIR and XRD results revealed that appropriate time of gaseous ozone treatment (2.5 and 7.5 min) enhanced short-range and long-range order structure due to the increased intermolecular oxidation crosslinking, whereas over treatment (15 and 20 min) caused degradation of the starch. With the increasing treatment time, apparent viscosity increased while breakdown viscosity, setback viscosity, swelling power and solubility decreased. OTBS exhibited a higher gelatinization enthalpy (Delta H) and a better viscoelasticity after gelation (6% OTBS gel, w/w). Additionally, OTBS-2.5 and OTBS-7.5 showed a decreased rapidly digested starch (RDS) content and increased resistant starch (RS) content, indicating that the digestible properties of two oxidized starches was decreased, which provide a feasible way to develop TBS as a new modified starch source.