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Summary: In this work, soy protein isolates (SPIs) were subjected to microparticulation, turning soy protein ingredients into microparticles with improved thermal stability which could be used in high‐protein foods. The pH is a critical determinant in microparticulation. Our work is mainly to investigate the effect of pH on the formation and properties of protein microparticles. To clarify the effects of pH conditions on the properties of the resulting particles, microparticulation was performed at different pH conditions (7.0, 6.0 and 5.0). Aggregation behaviours described by the parameters calculated from the protein dispersion viscosity combined with the observation of the morphology change were used to analyse the particle formation process. For the microparticles prepared at pH 5.0, soy proteins were more inclined to aggregate into clusters on a micro‐scale which had a flexible conformation. After spray drying, This powder could be easily dispersed in water, creating a dispersion with a protein concentration of 10 wt%. At this concentration, the thermal gelation capacity of the proteins was observed to decrease. Conversely, the tendency of protein aggregation was largely restricted when soy protein microparticulation was carried out at pH 7.0. As these soy protein particles in nano‐scale were dispersed in water, a decrease rather than an increase was recorded in the viscosity of this dispersion after it was heated, suggesting that these particles had improved thermal stability. This work has demonstrated that implementing appropriate pH conditions during microparticulation can prepare soy protein particles with different sizes and rheological properties, which might meet the demands of various food processing. [ABSTRACT FROM AUTHOR]

Summary: In this study, we aimed to evaluate the potential of the γ‐zein hydrolysate (γ‐ZH) as a new delivery system for hydrophobic bioactive molecules such as curcumin (Cur). γ‐ZH‐Cur complexes (γ‐ZH‐Cur) with a particle size of 50–60 nm were successfully formed via the hydrogen bonding and hydrophobic interactions. Compared to α‐ZH, the complexation of Cur in γ‐ZH showed a better improvement in the water solubility and physicochemical stability of Cur and showed sustained release and greater potential for absorption of Cur. The differences in the loading capability, the physicochemical storage and the bioaccessibility of Cur between γ‐ZH and α‐ZH may be associated with the differences in the amino acid composition and typical sequence of peptides. These results indicate that γ‐ZH has a better ability to serve as a novel delivery for the hydrophobic bioactive molecules compared to α‐ZH. [ABSTRACT FROM AUTHOR]

This work focused on the effect of glycosylation on the gelation ability of β-conglycinin induced by microbial transglutaminase ( MTGase). Rheological results indicated that the gels of β-conglycinin-dextran conjugate products exhibited higher G′ value (172.2 ± 8.6 Pa) compared with those of dry-heated β-conglycinin (75.2 ± 5.1 Pa), β-conglycinin (53.3 ± 4.0 Pa) and β-conglycinin-dextran mixture (38.6 ± 2.6 Pa) after 4 h incubation with MTGase. The gels prepared from β-conglycinin-dextran conjugate products had higher hardness, fracturability, springiness and cohesiveness values determined by textural profile analysis. The turbidity of β-conglycinin-dextran conjugate products solution incubated with MTGase increased faster than those of the other three protein samples. The conjugated dextran in β-conglycinin-dextran conjugate products could inhibit extensive protein-protein interactions which might result in the formation of more ordered and stronger gel network structures during MTGase cross-linking process. A compact and homogeneous gel networks in β-conglycinin-dextran conjugate products gels were also observed by scanning electron microscopy. [ABSTRACT FROM AUTHOR]