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Graphical abstract Highlights • Rapeseed peptide and d -xylose were used to develop Maillard reaction products. • Reaction with or without cysteine and various temperatures were considered. • High temperature promoted the formation of browning products and volatiles. • Cysteine addition was favor to generation of sulfur-containing compounds. • Furans and nitrogen oxides could be produced without cysteine. Abstract Rapeseed peptide was used to produce flavor enhancer via heating with d -xylose at various temperatures (80–140 °C) at reaction pH 7.4 for 2 h with or without l -cysteine (RXC or RX). Effects of temperatures and l -cysteine on the Maillard reaction products (MRPs) were investigated by the determinations of pH, color, free amino acids (FAA), and volatile compounds, as well as E-nose and E-tongue analyses. Partial least square regression (PLSR) method was further applied to explore the correlations. Results suggested that pH decreased more significantly in RXCs, and a more dark brown color was observed in RXs with the increase of heating temperatures. The lowest bitterness MRPs were obtained by heating at 140 °C with cysteine (RXC-140), while the highest umami and saltiness sample was found in RX-100. Bitter and umami FAAs were present in greater amounts at higher temperatures with cysteine. Furthermore, RXC showed a meat-like flavor due to the generation of sulfur-containing compounds, and more furans and nitrogen-containing compounds were detected in RX, along with a caramel-like flavor. [ABSTRACT FROM AUTHOR]

• SPI was modified by low pH shifting with hydrophobicity enhancement. • SPI-SPSS conjugates were easily obtained by Maillard reaction. • Submicro particles were formed by heating self-assembly reaction. • Improvement of hydrophobicity of SPI could promote submicron gelling properties. In the present study, the soybean protein isolate (SPI) was treated by pH shifting process, as the protein was incubated in low pH solutions (pH 1.5–3.5) for 12 h, following neutralized to pH 7.0 and held for 4 h, which resulted in a conformation unfolding/refolding confirmed by the fluorescence spectra and a substantial increase in α-helix content revealed by circular dichroism (CD) spectra, along with the increased exposure of hydrophobic and sulfhydryl groups. In addition, the heat-induced gelation process and enhanced gel strength of pH 3.0 and 3.5 shifted SPIs were observed. Maillard reaction was then applied and the glycosylated SPI was further applied to the sub-micron gel particles formation. Results showed that low-pH shifting obviously improve the glycosylation ability of SPI as the conjugation degree and browning degree were enhanced. The sub-micron gel particles with core–shell structure and the average sizes of 100–250 nm were formed via heating self-assembly reaction and confirmed through Z-average of particle size, meanwhile, the increasing stability of gel particles in the solution was determined by Zeta potential analysis, suggesting that the improvement of hydrophobicity and glycosylated ability of SPI could promote gelling properties. Hence, the protein modification stage of pH shifting process would provide a great potential application in the formation of nano- or microscale gel particles. [ABSTRACT FROM AUTHOR]