Starch-Based Multilayer with pH-Responsive Behavior Driven by Whey Protein Concentrate: The Effect of Starch Conformation
Journal
Starch/Staerke
Journal Volume
72
Journal Volume
72
Journal Issue
7-8
Journal Issue
7-8
Start Page
1900277
ISSN
00389056
Date Issued
2020-07-01
Author(s)
Chang, Shing-Yun
Abstract
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.
Subjects
anthocyanins
cationic starch
layer-by-layer multilayers
pH-triggered release
whey protein concentrates
Publisher
Wiley-VCH Verlag
Type
journal article