The selective encapsulation and stabilization of cinnamaldehyde and eugenol in high internal phase Pickering emulsions: Regulating the interfacial properties.

This work aimed to investigate the encapsulation and stabilization mechanism of cinnamaldehyde and eugenol in high internal phase Pickering emulsions (HIPPEs) through regulating their interfacial rheological properties and interfacial microstructure. With the incorporation of cinnamaldehyde, the Schiff base reaction between the cinnamaldehyde and proteins favored the formation of the predominantly elastic and solid-like interfacial layers. In contrast, the hydrogen bonds between eugenol and proteins resulted in the transformation of interfacial layers to viscous dominant with weak viscoelastic responses. Thus, cinnamaldehyde-loaded HIPPEs had a better storage stability than eugenol-loaded HIPPEs, and the retention rate was increased by about 15 %∼20 %. The addition of tea camellia seed oil inhibited the mobility of immobilized water and improved the retention rates of cinnamaldehyde and eugenol by approximately 6 % and 12 % (30 days at 25 °C), respectively. These findings will be beneficial for the development and design of effective essential oil encapsulation systems in the food industry.

High internal phase pickering emulsions stabilized by pea protein isolate-high methoxyl pectin-EGCG complex: Interfacial properties and microstructure.

The pea protein isolate-high methoxyl pectin-epigallocatechin gallate (PPI-HMP-EGCG) complex was used to stabilize Pickering emulsions (PEs) and high internal phase PEs (HIPPEs), and the effect of interfacial rheology on the microstructure, bulk rheology and stability of these emulsions was investigated. The PPI-HMP-EGCG complex with PPI to EGCG 30:1 exhibited partial wettability (81.6 ± 0.4°) and optimal viscoelasticity for the formation of stable interfacial layer. The microstructure demonstrated that the PPI-HMP-EGCG complex acted as an interfacial layer and surrounded the oil droplets, and continuous phases were mainly filled with excessive HMP, which enhanced emulsion stability. The formation of a firm gel-like network structure required a dense interfacial layer to provide the PEs (complex concentration of 0.1%) and HIPPEs (oil-phase up to 0.83) with ideal viscoelasticity and stability. The results provide the guidelines for the rational design of EGCG-loaded HIPPEs stabilized by water-soluble protein/polysaccharide complexes.

Preparation and pH stability of ferrous glycinate liposomes.

Ferrous glycinate liposomes were prepared by reverse phase evaporation method. The effects of cholesterol, Tween 80, ferrous glycinate concentration, hydrating medium, pH of hydrating medium, and sonication strength on the encapsulation efficiency of liposomes were investigated. Encapsulation efficiency was significantly influenced by the different technique parameters. Ferrous glycinate liposomes might be obtained with high encapsulation efficiency of 84.80% under the conditions of optimized technique parameters. The zeta potential and average particle size of liposomes in the hydrating medium of pH 7.0 were 9.6 mV and 559.2 nm, respectively. The release property of ferrous glycinate liposomes in vitro was investigated in simulated gastrointestinal juice. A small amount of ferrous glycinate was released from liposomes in the first 4 h in simulated gastrointestinal juice. The mean diameters of liposomes increased from 559.2 to 692.9, 677.8, and 599.3 nm after incubation in simulated gastrointestinal juice of pH 1.3, 7.5, and 7.5 in the presence of bile salts, respectively. Results showed that the stability of ferrous glycinate in strong acid environment was greatly improved by encapsulation in liposomes, which protected ferrous glycinate from disrupting the extracapsular environment by lipid bilayer. The bioavailability of ferrous glycinate, as the iron source for biological activity including hemoglobin formation, may be increased. The ferrous glycinate liposomes may be a kind of promising iron fortifier.

Optimization of cross-linking parameters during production of transglutaminase-hardened spherical multinuclear microcapsules by complex coacervation.

Gelatin-gum arabic spherical multinuclear microcapsules (SMMs) encapsulating peppermint oil were prepared by complex coacervation. Transglutaminase (TG) was used to harden the SMMs by complex coacervation instead of traditional reagents such as formaldehyde or glutaraldehyde. The effect of various cross-linking parameters on the hardening effectiveness of SMMs containing peppermint oil was investigated. The optimum parameters were as follows: hardening for 6h at 15 degrees C and pH 6.0 with a TG concentration of 15 U/g gelatin. Compared with formaldehyde, TG exhibits similar microcapsule hardening effectiveness.