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 Food Science and Technology, Jiangnan University, Wuxi 214122, China; Collaborative Innovation Center of Food Safety and Quality Control in Jiangsu Province, Jiangnan University, Wuxi 214122, China.
Int J Biol Macromol. 2021 Dec 15;193(Pt B):1744-1751. doi: 10.1016/j.ijbiomac.2021.11.011. Epub 2021 Nov 6.
The aim of this study was to examine the effect of whey protein isolate (WPI) on the digestibility and physicochemical properties of potato starch (PS) after heat treatment. WPI reduced the digestibility of PS and increased the order and aggregation structure of gelatinized PS. Examination of the rheological properties of the PS-WPI mixed system before and after adding different chemicals (sodium chloride, urea, and sodium dodecyl sulfate) indicated an involvement of hydrogen bonds and hydrophobic interactions in the PS-WPI gelatinization system. The pasting properties, swelling power, and thermal properties indicated that WPI suppressed the swelling and gelatinization of PS. The addition of WPI reduced the amylose leaching rate from the starch granules, indicating that the presence of exogenous protein could prevent amylose diffusion from the starch granules. Native WPI and its hydrolysate also inhibited amyloglucosidase activity. These findings indicated that the mechanism by which WPI reduces PS digestion involves hydrophobic interactions and hydrogen bonding between WPI and PS, as well as enzyme activity inhibition.
本研究旨在探讨乳清蛋白分离物（WPI）对热处理后马铃薯淀粉（PS）消化率和理化性质的影响。WPI 降低了 PS 的消化率，并增加了糊化 PS 的有序性和聚集结构。考察了添加不同化学物质（氯化钠、尿素和十二烷基硫酸钠）前后 PS-WPI 混合体系的流变性质，表明氢键和疏水相互作用参与了 PS-WPI 糊化体系。糊化特性、溶胀能力和热性质表明 WPI 抑制了 PS 的溶胀和糊化。添加 WPI 降低了淀粉颗粒中直链淀粉的浸出率，表明外源蛋白的存在可以阻止直链淀粉从淀粉颗粒中扩散。天然 WPI 及其水解产物也抑制了淀粉酶的活性。这些发现表明，WPI 降低 PS 消化率的机制涉及 WPI 与 PS 之间的疏水相互作用和氢键，以及酶活性抑制。
