School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China; State Key Laboratory of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China.
Department of Food Science, University of Massachusetts, Amherst, MA 01003, USA.
Food Chem. 2021 Aug 15;353:129468. doi: 10.1016/j.foodchem.2021.129468. Epub 2021 Mar 7.
The impacts of two hydrothermal pretreatments, annealing (ANN) and heat moisture treatment (HMT), on oil-absorption by normal maize starch (NMS) during frying were investigated using low-field nuclear magnetic resonance (LF-NMR). The structural organizations of the fried samples were also evaluated using SEM, XRD, ATR-FTIR, and DSC, respectively. Both hydrothermal pretreatments significantly reduced the total oil content in the starch after frying, with the magnitude of the effect depending on the treatment conditions used. SEM showed that the pretreated fried starch granules preserved more of their original morphology. XRD, FTIR, and DSC showed that both pretreatments preserved more of the short-range double helices and long-range organizations within the orthorhombic crystalline structure for NMS during frying. The promoting effect of ANN/HMT on the interactions of starch molecules and the rearrangement of double helices were hypothesized to be responsible for the increased thermal stability of starch granules in the present work. As a result, fried starch pretreated by ANN/HMT were more organized and more compact than fried NMS, thus inhibiting oil absorption during frying.
采用低场核磁共振（LF-NMR）研究了退火（ANN）和湿热处理（HMT）两种水热处理对油炸过程中普通玉米淀粉（NMS）吸油的影响。还分别使用 SEM、XRD、ATR-FTIR 和 DSC 评估了油炸样品的结构组织。两种水热处理均显著降低了油炸后淀粉中的总油含量，其影响程度取决于所使用的处理条件。SEM 表明，预处理后的油炸淀粉颗粒保留了更多的原始形态。XRD、FTIR 和 DSC 表明，两种预处理均在油炸过程中保持了更多的 NMS 中短程双螺旋和长程正交晶结构内的组织。假设 ANN/HMT 对淀粉分子相互作用的促进作用和双螺旋的重排是导致本工作中淀粉颗粒热稳定性增加的原因。因此，经 ANN/HMT 预处理的油炸淀粉比未经处理的 NMS 更有组织且更紧凑，从而抑制了油炸过程中的吸油。
