The present work deals with the preparation and stabilization of zein colloidal particles using sodium caseinate as electrosteric stabilizer. Colloidal particles with well-defined size range (120-150 nm) and negative surface potential (-29 to -47 mV) were obtained using a simple antisolvent precipitation method. Due to the presence of caseinate, the stabilized colloidal particles showed a shift of isoelectric point (IEP) from 6.0 to around pH 5.0 and thus prevent the aggregation of zein near its native IEP (pH 6.2). The particles also showed good stability to varying ionic strength (15 mM-1.5 M NaCl). Furthermore, stabilized particles retained the property of redispersibility after drying. In vitro protein hydrolysis study confirmed that the presence of caseinate did not alter the digestibility of zein. Such colloidal particles could potentially serve as all-natural delivery systems for bioactive molecules in food, pharmaceutical, and agricultural formulations.

The formation and characterization of a novel class of all‐natural digestible microcapsules containing a liquid lipid core encapsulated by a water‐insoluble protein shell with tunable thickness is demonstrated. As an example of a water‐insoluble protein, zein is used—the protein of corn—which is an attractive biomaterial from a sustainable source. The microcapsules are prepared by a direct and simple method, based on the precipitation of protein from the continuous phase of an oil‐in‐(water/ethanol) emulsion onto the oil droplets without the need of any surfactant. The shell thickness can be controlled by the amount of precipitated protein. An in vitro digestion assay is performed to study the lipid hydrolysis and biodegradability. The rate of lipid hydrolysis and release of fatty acids are highly dependent on the protein shell thickness. All‐natural edible microcapsules with controlled degradation under gastrointestinal conditions can enable new applications for oral delivery systems. They may further be used as a model system for controlled release studies of lipophilic compounds and could promote the sustainable use of underutilized water insoluble proteins as functional biomaterials.

When this particular fat at these amounts is delivered in a meal replacement drink, droplet size does not influence appetite or food intake. This effect is independent of the amount of fat or plasma cholecystokinin changes.

A stable, all‐natural, edible, core–shell microcapsule from zein, a protein of corn, and oil is synthesized by E. Filippidi, K. P. Velikov, and colleagues in a one‐step process without the use of any stabilizers or surfactants. On page 5962, the zein shell thickness can be controlled and imparts functionality, controlling the rate of hydrolysis of the encapsulated oil (triacylglycerides). The capsules pass the gastric phase and break down in the intestine.