Department of Food Science, College of Agriculture and Life Sciences, Cornell University, Ithaca, New York, USA.
Dairy Management Inc., Rosemont, Illinois, USA.
J Food Sci. 2024 Sep;89(9):5488-5502. doi: 10.1111/1750-3841.17182. Epub 2024 Aug 1.
The poor thermal stability of lactoferrin (LF) hinders its bioavailability and use in commercial food products. To preserve LF from thermal denaturation, complexation with other biopolymers has been studied. Here we present the complex formation conditions, structural stability, and functional protection of LF by α-lactalbumin (α-LA). The formation of the LF-α-LA complexes was dependent on pH, mass ratio, and ionic strength. Changing the formation conditions and cross-linking by transglutaminase impacted the turbidity, particle size, and zeta-potential of the resulting complexes. Electrophoresis, Fourier-transform infrared spectroscopy, and circular dichroism measurements suggest that the secondary structure of LF in the LF-α-LA complex was maintained after complexation and subsequent thermal treatments. At pH 7, the LF-α-LA complex protected LF from thermal aggregation and denaturation, and the LF retained its functional and structural properties, including antibacterial capacity of LF after thermal treatments. The improved thermal stability and functional properties of LF in the LF-α-LA complex are of interest to the food industry.
乳铁蛋白（LF）的热稳定性差，限制了其在商业食品中的生物利用度和应用。为了防止 LF 发生热变性，研究了与其他生物聚合物的复合。本研究介绍了 LF 与α-乳白蛋白（α-LA）形成复合物的条件、结构稳定性和功能保护。LF-α-LA 复合物的形成取决于 pH 值、质量比和离子强度。改变形成条件和通过转谷氨酰胺酶交联会影响所得复合物的浊度、粒径和 ζ 电位。电泳、傅里叶变换红外光谱和圆二色性测量表明，LF 在 LF-α-LA 复合物中的二级结构在复合物形成和随后的热处理后得以保持。在 pH7 时，LF-α-LA 复合物保护 LF 免受热聚集和变性，并且 LF 保留了其功能和结构特性，包括 LF 经热处理后的抗菌能力。LF-α-LA 复合物中 LF 的热稳定性和功能特性的改善对食品工业具有重要意义。
