Interfacial properties of whey protein foams as influenced by preheating and phenolic binding at neutral pH
Interfacial properties of whey protein foams as influenced by preheating and phenolic binding at neutral pH
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DOI：
10.1016/j.foodhyd.2018.04.020
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发表时间：
2018-09-01
影响因子：
10.7
通讯作者：
True, Alma D.
中科院分区：
文献类型：
--
作者：
Cao, Yanyun;Xiong, Youling L.;True, Alma D.
研究了预热和酚处理对乳清分离蛋白（WPI）在空气-水界面上的吸附行为和随后的起泡性能的影响。在pH 7.0下，天然WPI（NWPI）和热解折叠（80 ℃，9分钟）WPI（HWPI）与没食子酸（GA）或表没食子儿茶素没食子酸酯（EGCG）相互作用。酚类处理使蛋白质的二级结构紊乱程度略有增加，表面疏水性显著降低，而EGCG的作用更为显著。通过等温滴定量热法进一步证实了蛋白质-酚结合。NWPI和HWPI（10 mg/mL）能够在空气-水界面上吸附形成弹性膜，吸附过程以蛋白质在界面上的解折叠和重排为主。预热显著提高了乳清蛋白在气-水界面上的动态表面压力（pi），降低了乳清蛋白在气-水界面上的动态弹性（E-d）。热诱导的蛋白质聚集导致泡沫稳定性增强。GA和EGCG诱导不同的模式的时间依赖性的p进化，这是密切相关的酚浓度。两种酚类化合物均通过减弱蛋白质在界面处的相互作用来抑制蛋白质膜的艾德。然而，发泡性能显着增强，除了240 μ mol/g的EGCG处理的HWPI，这是由泡沫图像证实在所有酚浓度。(c)2018爱思唯尔有限公司版权所有
The impact of preheating and phenolic treatment on the adsorption behavior at the air-water interface and subsequent foaming properties of whey proteins isolate (WPI) was investigated. Native WPI (NWPI) and heat-unfolded (80 degrees C for 9 min) WPI (HWPI) were interacted with gallic acid (GA) or epigallocatechin gallate (EGCG) at pH 7.0. Phenolic treatment slightly increased the unordered secondary structure and significantly decreased the surface hydrophobicity of proteins whereas the effect of EGCG was more remarkable. The protein-phenolic binding was further confirmed by isothermal titration calorimetry. NWPI and HWPI (10 mg/mL) were able to adsorb at the air-water interface to form an elastic film and the adsorption process was dominated by protein unfolding and rearrangement at the interface. Pre-heating significantly improved the dynamic surface pressure (pi) and depressed the dilatational elasticity (E-d) of whey proteins adsorbed at the air-water interface. The heat-induced protein aggregation led to an enhanced foam stability. GA and EGCG induced different patterns of time-dependent p evolution, which were closely related to the phenolic concentration. Both phenolics suppressed the Ed of protein film via weakening protein interactions at the interface. However, foaming properties were significantly enhanced at all phenolic concentrations except for the 240 mu mol/g EGCG-treated HWPI, which was corroborated by the foam image. (c) 2018 Elsevier Ltd. All rights reserved.