Effects of phenols with different structure characteristics on properties of potato starch: Action rule and molecular mechanism

Four phenols (protocatechuic acid, ellagic acid, naringin, and tannic acid), could affect the particle size and microstructures of potato starch, while the action sequence was as: tannic acid > naringin > ellagic acid > protocatechuic acid. Meanwhile, all phenols could decrease the thermal stability of potato starch and changed its crystallinity. In addition, hydrogen bonds were determined as the main molecular force between phenols and potato starch. Furthermore, molecular dynamics simulation indicated that phenols could significantly affect the spatial configuration of starch molecules by changing the formation of hydrogen bonds, and phenols with more hydroxyl groups and higher molecular weight exhibited stronger binding effects than simple phenols. All present results suggested that the hydroxyl groups amount and molecular weight of phenols could affect their effects on starch molecules, so as to significantly affected the properties of potato starch, which showed the potential application in chemical and food industries. Novelty impact statement Phenols affected the properties of potato starch and changed the spatial configuration of starch molecules by a hydrogen bond. Phenols action sequence was: tannic acid > naringin > ellagic acid > protocatechuic acid, and more hydroxyls and higher molecular weight promoted the effects of phenols on starch.