State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi 214122, China; School of Biological Sciences, The University of Hong Kong, Pokfulam, Hong Kong Special Administrative Region, China; School of Food Science and Technology, Jiangnan University, Wuxi 214122, China.
Food Chem. 2022 May 1;375:131677. doi: 10.1016/j.foodchem.2021.131677. Epub 2021 Nov 27.
The existence of microwave non-thermal effects in food processing is still debated. In this study, molecular dynamics (MD) simulations were performed to investigate the conformation, electrostatic profiles, and intramolecular hydrogen bonds (intra-HB) of glucose in aqueous solution under alternating electric fields of microwaves ranging from 0 to 10 V/m at 2.45 GHz. The results showed a field-induced threshold of 10 V/m. At the threshold, alternating microwaves reoriented the flexible moieties and thus enhanced the intra-HB. The conformational transition among gg, gt, and tg conformers at 10 V/m possibly resulted from the uneven electrostatic potential and the increased intra-HB. In practice, the maximum electric field of microwaves is several times weaker than the threshold, verifying the absence of microwave non-thermal effects for glucose molecules in food processing. This study provides a novel strategy to evaluate the potential non-thermal effects of microwaves in food processing and the related underlying food safety issues.
微波非热效应对食品加工的影响仍然存在争议。本研究采用分子动力学（MD）模拟方法，在 2.45GHz 微波频率下，研究了 0 至 10V/m 交变电场中葡萄糖在水溶液中的构象、静电势分布和分子内氢键（intra-HB）。结果表明，存在一个 10V/m 的场诱导阈值。在阈值处，交变微波会重新定向柔性部分，从而增强 intra-HB。在 10V/m 下，gg、gt 和 tg 构象之间的构象转变可能是由于不均匀的静电势和增强的 intra-HB 所致。在实际应用中，微波的最大电场强度远弱于阈值，这验证了微波非热效应对食品加工中葡萄糖分子的不存在。本研究为评估微波在食品加工中的潜在非热效应及相关食品安全问题提供了一种新的策略。
