Relatively high‐branched cationic (NCS) and linear cationic starches (HCS) are prepared, to construct multilayers with whey protein concentrate (WPC) via layer‐by‐layer (LbL) deposition. As expected, the pH responsive behavior of the multilayers is observed to depend on the charge reversal of WPC. The build‐up and break‐down of multilayers differ with the conformation of the cationic starches. WPC tends to be trapped in the NCS layers, while WPC adsorbs onto the HCS layer and increases the coverage laterally. Despite the strong screening effect of salt in 0.1 m NaCl, both multilayers show a significant structural change at pH < pI (4.3) of WPC due to the emergent repulsive force in the multilayers. The HCS‐based multilayer shows a clear structural dissociation, while the NCS‐based multilayer undergoes a structural disruption along with swelling of the entangled NCS layers. Finally, anthocyanins are post‐loaded into the NCS‐based multilayer and their pH‐dependent release is in agreement with the structural integrity driven by WPC. Given the rapid pH response and the feasible post‐loading technique, the potential of such multilayers to act as pH‐triggered active coatings is evident.

中文翻译：

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乳清蛋白浓缩物驱动的具有pH响应行为的淀粉基多层膜：淀粉构象的影响

制备了相对较高支化的阳离子（NCS）和线性阳离子淀粉（HCS），以通过逐层（LbL）沉积与乳清蛋白浓缩物（WPC）构建多层。如所预期的，观察到多层的pH响应行为取决于WPC的电荷反转。多层的堆积和分解随阳离子淀粉的构象而不同。WPC倾向于被困在NCS层中，而WPC吸附到HCS层上并横向增加覆盖率。尽管盐分在0.1 m内有很强的屏蔽作用由于多层中出现排斥力，两个多层的NaCl在WPC的pH <pI（4.3）时均显示出显着的结构变化。基于HCS的多层显示出清晰的结构解离，而基于NCS的多层经历了结构破坏以及缠结的NCS层膨胀。最后，花青素被后装到基于NCS的多层膜中，它们的pH依赖性释放与WPC驱动的结构完整性一致。鉴于快速的pH响应和可行的后装技术，这种多层材料可作为触发pH的活性涂料的潜力是显而易见的。