Fabrication and characterization of complex coacervates utilizing gelatin and carboxymethyl starch

Abstract

BackgroundIn comparison to native polysaccharides, modified polysaccharides have greatly expanded applications due to their improved compatibility and interactions with proteins and active compounds in the realm of food‐related areas. Nonetheless, there is a noticeable dearth of research concerning the utilization of carboxymethyl starch (CMS) as a microcapsule wall material in food processing despite its common use in pharmaceutical delivery. Therefore, the development of an economical and safe embedding carrier using CMS and gelatin (GE) holds immense importance within the food processing industry. In this work, the potential of innovative coacervates formed by the combination of GE and CMS as a reliable, stable, and biodegradable embedding carrier was evaluated by turbidity measurements, thermogravimetric analysis (TGA), X‐ray diffraction (XRD), Fourier‐transform infrared (FT‐IR) spectroscopy, and rheological measurements.ResultsThe results indicate that GE‐CMS coacervates primarily resulted from electrostatic interactions and hydrogen bonding. The optimal coacervation was observed at pH 4.6 and a GE/CMS blend ratio of 3:1 (w/w). However, the addition of NaCl reduced coacervation and made it less sensitive to temperature changes (35–55°C). Compared to individual GE or CMS, the coacervates exhibited higher thermal stability, as shown by TGA. Importantly, XRD analysis shows that the GE‐CMS coacervates maintained an amorphous structure. Rheological testing reveals that the GE‐CMS coacervates exhibited shear‐thinning behavior and gel‐like properties.ConclusionOverall, attaining electroneutrality in the mixture boosts the formation of a denser structure and enhances rheological properties, leading to promising applications in food, biomaterials, cosmetics, and pharmaceutical products.This article is protected by copyright. All rights reserved.