Preparation and characterization of sesame peptide-calcium chelate with different molecular weight

Sesame peptides could be used to treat underlying diseases and a suitable carrier of nutrients. In this study, sesame peptides were mainly prepared from SSM (sesame meal), and the chelating ability of different molecular weight sesame peptide components to calcium and the physical characterization of the chelates were investigated. After that, the molecular weights were verified by HPLC (high performance liquid chromatography), and the Zeta potential, PDI (polydispersity) of SSMP (sesame meal peptides) of different molecular weights were determined. In the SSMP-Ca chelates, the chelation rate of SSMP-2 (sesame meal peptide components 2) to calcium is 72.72 ± 0.17%. Fluorescence spectrum analysis found that the fluorescence intensity of chelates decreased, and the maximum absorption peak was red-shifted. FT-IR (Fourier Transform Infrared spectroscopy) research showed that the chelate vibration absorption wavelengths of the three characteristic peaks -NH2, COO−, and C = O had change, indicating that the amino and carboxyl groups in sesame peptide participated in the chelation reaction. SEM (scanning electron microscope) analysis showed that SSMP and calcium could form a chelate with specific stability. Most of its microstructures were encapsulated and adhered to each other to create a "bridging effect" and appear as aggregates. These results provided a basis for using sesame peptides in the food or pharmaceutical industry.