# Cooperative Stabilization of Pickering Emulsions by Starch and Chitin Nanoparticles: Roles of Ball-Milling, Gelatinization, Adsorption, and Viscosity Behavior

## TL;DR

Starch and chitin nanoparticles together stabilize oil-water emulsions better than either alone, offering a sustainable and cost-effective solution.

## Contribution

A synergistic stabilization mechanism of Pickering emulsions using starch and chitin nanoparticles is revealed, with a 1:1 ratio showing optimal performance.

## Key findings

- A 1:1 ratio of starch and chitin nanoparticles provides superior emulsion stability compared to other ratios.
- Thermal pretreatment improves emulsion stability, maintaining droplet size for four months.
- Chitin nanoparticles form a colloidal network in the continuous phase, preventing droplet mobility and Ostwald ripening.

## Abstract

We demonstrate enhanced Pickering emulsion stabilization
by modified
starch nanoparticles (SNP) through their combination with chitin nanocrystals
(ChNC). The effect of the biopolymer’s ratio on the emulsion
stabilization mechanisms was elucidated based on their role at the
interface and bulk phases. The stabilization achieved with a 1:1 (SNP:ChNC)
ratio surpasses that of other ratios studied, exhibiting a synergistic
effect compared with neat SNP and the 10:1 and 5:1 systems. Emulsion
stability was further improved by applying thermal pretreatment to
the aqueous phase before homogenization. The heat-treated 1:1 emulsion
maintained a consistent droplet size (∼3.4 μm) over four
months, even after slow creaming. This stability is attributed to
SNP adsorption at the oil–water interface, providing a mechanical
barrier to droplet’s coalescence, while ChNC is also present
in the oil–water interface and forms a colloidal network in
the continuous phase, hindering droplet’s mobility and preventing
Ostwald ripening. These findings expand the application of chitin
as an emulsifier and address the rising demand for healthier and sustainable
emulsified formulations with reduced costs.