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In order to develop new plant protein-based lipid substitutes to deal with health problems caused by animal fats or trans -fatty acids, the emulsion stablized by acid-heat (90 °C, pH 2.0) induced aggregation of peanut protein isolate (PPI) was used as template to fabricate oleogels. Heating time affected the structure, morphology of PPI and the adsorption characteristics at the O/W interface. The protein with suitable heating time (2–6 h) formed fibrils structure, which was beneficial to the rapid adsorption of aggregates at the O/W interface. Overheating (exceeding 8 h) led to the aggregate of protein fibrils and inhibited the adsorption of proteins at the O/W interface. Therefore, the heating times of 2 h, 4 h and 6 h were selected to prepare the follow-up emulsion and oleogels. Among the four heating times, the emulsion prepared by PPI heating for 6 h showed the best storage stability, ionic strength stability and shear resistance. The resultant oleogels exhibited the least oil loss and the highest freeze-thaw stability. The margarita biscuits prepared with a substitution rate of 50% oleogels to butter presented similar sensory property to the margaritas prepared with butter, indicating that the oleogels possessed favorable shortening properties. The results indicated that PPI fibrils structure could improve the oleogel formaton properties, making it a potential novel additive for the development of new fat substitute products. [Display omitted] • Peanut protein isolate (PPI) fibrils were formed by acid-heating induction. • Fibrillation improved the emulsifying performance of PPI. • Oleogels obtained by PPI fibril emulsion template showed higher freeze-thaw stability. • Replacing butter with oleogel had no significant impact on biscuit sensory attributes. [ABSTRACT FROM AUTHOR]

To investigate the effect of molecular weight of saccharides and heating time on interfacial behavior of protein, glycated rice bran protein aggregates (gRBPAs) were obtained by incubating rice bran protein (RBP) with glucose (Glu), maltose (Mal) and dextran (Dex) via acid-heat treatment (pH 2.0, 90 °C). Subsequently, the stability and in vitro simulated digestion properties of oil in water (O/W) emulsion stabilized by gRBPAs were analyzed. Structural analysis (circular dichroism and fluorescence spectra) proved that the tertiary structure and secondary structure of RBP changed after glycation, and the contents of β-sheet structure of gRBPAs increased significantly. Besides, the glycation improved the interfacial activity and emulsification of protein obviously. Compared with Glu or Mal, the grafting of Dex could produce larger steric hindrance, which better inhibited the aggregation of emulsion droplets. Furthermore, glycation enhanced the pancreatic lipase (PL) inhibitory activity of gRBPAs obviously, and the emulsions stabilized by gRBPAs exhibited higher anti-digestion ability (62.12–75.00%) compared with RBP (95.27%). Moreover, the free fatty acid (FFA) rate of O/W emulsion was closely related to the surface hydrophobicity, degree of glycation, PL inhibitory activity and interfacial behavior of gRBPAs. Therefore, these findings would be enlightening to intuitively tailor the physicochemical stability and digestibility of O/W emulsion system according to heating time and molecular weight of saccharides. Meanwhile, this work would facilitate the application of O/W emulsion stabilized by glycated protein aggregates in functional foods. [Display omitted] • O/W emulsions stabilized by glycated rice bran protein aggregates were constructed. • Glycation changed the tertiary structure and secondary structure of protein. • Glycation improved the interfacial activity and emulsification of protein. • Glycation tailored the stability and in vitro digestion properties of emulsions. • Interfacial protein content was negatively correlated with FFA release rate. [ABSTRACT FROM AUTHOR]

To design a delivery system with effective protective attribute for lutein and explore the effect of the peptides conjugated with different phenolics on the carrier performance, zein peptide was covalently bonded to three phenolic acids, i.e. vanillic acid, protocatechuic acid, and gallic acid, to form the corresponding phenolic acid-zein peptide conjugates as stabilizers for preparing emulsion gels with sodium alginate and Ca2+. The emulsifying activity of the peptide was significantly increased by 49%–76% after the conjugation. The presence of the hydrophobic methoxy group on the benzene ring of vanillic acid contributed to the highest surface hydrophobicity of the corresponding conjugate, while the more hydrophilic phenolic hydroxyl groups of protocatechuic acid and gallic acid resulted in lower surface hydrophobicity for their conjugates. Among all the emulsion gels, the gel fabricated by vanillic acid-zein peptide conjugate exhibited the tightest network structure, the most favorable thixotropy with the recovery rate of 82%, the highest storage stability and UV protective effect for lutein. The in vitro digestion demonstrated that the gel with a more tight structure achieved the lower free fatty acids release rate and bioaccessibility. These findings suggest that the hydrophobicity of phenolic acids inflences the controllable release and protective effect for hydrophobic bioactives of the emulsion gels based on their covalent conjugates with zein peptides. • Three phenolic acids, VA, PA and GA were covalently conjugated with zein peptide. • Hydrophobicity of phenolic acids affected the interface performance of the conjugates. • Emulsion gels prepared by the conjugates provided effective protection for lutein. • FFA release rate was positively correlated with lutein bioavailability. • Lutein bioavailability was negatively correlated with storage modulus of emulsion gel. [ABSTRACT FROM AUTHOR]