RESUMEN
High-pressure homogenization and pH-shifting can be used to modify soybean lipophilic protein (SLP), and to enhance its ability to deliver vitamin B12. The structural changes of SLP were analyzed by multispectral techniques and the results showed that secondary and tertiary structures of SLP were altered by modification. The modification unfolded the SLP structure, released more free hydrogen ions, and increased positive charge density on the protein surface. Also, the solubility of modified SLP increased by maximum of 34.75 %. Furthermore, molecular docking showed that complexes were formed between SLP and vitamin B12 mainly through hydrogen bonding and hydrophobic interactions, and the encapsulation rate of modified SLP was maximally increased by 2.3 %. In vitro digestion showed that modified SLP enhanced stability and bioaccessibility of vitamin B12. This study provides theoretical basis for modification of SLP and effective delivery of bioactive substances.
RESUMEN
In this experiment, the co-constructed O/W emulsions of different soy protein hydrolysates (SPHs) and gum arabic (GA) were investigated. SPHs were prepared by hydrolyzing soy protein isolate (SPI) using different enzymes, and investigated the effects of enzyme types and hydrolysis time on the physicochemical properties of SPHs. Moreover, SPI/GA and SPHs/GA were prepared and used as hydrophilic emulsifiers to construct O/W emulsions. The results showed that the optimal hydrolysis times for bromelain, pepsin and trypsin were 2 h (BSPH2), 3 h (PSPH3) and 3 h (TSPH3), respectively. Compared with SPI/GA emulsions, SPHs/GA emulsions had smaller particle size, more negative charge, higher interfacial adsorbed protein, and more stable emulsion systems. During the digestion process, SPHs/GA emulsions were effective in realizing the release of bioactives. In conclusion, enzymatic hydrolysis can be an effective modification technique, and SPHs/GA can be used as an effective emulsifier for the emulsion system.