Abstract: Three lactoferrin-pectin complexes (MLFP, MPLF and MLFP) were prepared by treatment with dynamic high pressure microfluidization (DHPM) in different sequences. MLFP was obtained by mixing lactoferrin (LF) pretreated by DHPM with pectin (P), MPLF was obtained by mixing pectin pretreated by DHPM with LF, and MLFP was obtained by mixing LF with pectin and then treating the mixture by DHPM. The present study was undertaken to explore the effect of DHPM treatment sequences on the properties and structure of LF-P complexes. The results showed that DHPM treatment increased the dispersibility, but reduced the emulsifying properties of LF-P complexes. Among the three complexes, MLFP had the highest dispersibility and emulsifying properties, while MLFP had the lowest dispersibility and emulsifying properties. This result was consistent with the results of interfacial tension measurement. The particle sizes of the complexes were significantly reduced compared to the control prepared without DHPM treatment (P < 0.05), in the increasing of MPLF < MLFP < MLFP < control. The formation of the complexes was driven by electrostatic interaction between pectin and LF, as confirmed by ζ-potential measurement and infrared spectroscopy, and DHPM treatment promoted this interaction. This study provides a theoretical basis for exploring the changes in the structure and properties of food components during food processing.

Key words: lactoferrin, pectin, complex, dynamic high pressure microfluidization, interaction