pH-dependent protein–alginate interactions shape gel structure, protein release and in vitro digestion.

Title: pH-dependent protein–alginate interactions: physicochemical, structural, and digestion data

Description:
This dataset contains raw and processed experimental data supporting the article “pH-dependent protein–alginate interactions shape gel structure, protein release and in vitro digestion”. It provides a complete record of how pH modulates the interactions between sodium alginate and plant proteins (soy protein isolate, SPI; hemp protein isolate, HPI; and pea protein isolate, PPI), and how these interactions influence bead formation, entrapment efficiency, and gastrointestinal stability.

Contents:

Protein solubility data: Solubility (%) of SPI, HPI, and PPI measured across pH 2–7.

Zeta potential data: Apparent surface charge (mV) of proteins and alginate across pH 2–7, showing charge inversion near isoelectric points.

FTIR spectral data: Absorbance values in the amide I and II regions (1600–1700 cm⁻¹), highlighting conformational changes and protein–alginate interactions at pH 4 and 7.

Bead morphology: Diameter and sphericity factor of alginate–protein beads produced at pH 4 and 7, with confocal microscopy images showing protein and alginate distribution.

Entrapment efficiency (EE): Protein retention capacity of alginate–protein beads, including maximum EE values.

Protein release kinetics: Protein release profiles during simulated gastrointestinal digestion (oral, gastric, intestinal phases) following the INFOGEST protocol.

Peptide size distribution: High-performance size exclusion chromatography (SEC) data showing generation of bioaccessible peptides smaller than 300 Da.

Methodology:
Data were generated using standardized protocols: Pierce™ BCA Protein Assay for solubility and release quantification, Zetasizer Nano ZS for zeta potential, ATR-FTIR spectroscopy for molecular interactions, bead production via external gelation with CaCl₂, confocal laser scanning microscopy for bead structure, and the INFOGEST static in vitro digestion protocol for protein release and proteolysis. SEC analysis was performed to determine peptide size distribution.

Potential Use:
This dataset provides a comprehensive view of pH-dependent protein–alginate interactions, offering valuable insights for researchers in food science, encapsulation technologies, and biopolymer chemistry. It is particularly relevant for the development of plant protein-based delivery systems and controlled-release applications.

Keywords: protein–alginate interactions, solubility, zeta potential, FTIR, hydrogel beads, entrapment efficiency, in vitro digestion, peptide bioaccessibility, soy protein isolate, hemp protein isolate, pea protein isolate.