Interfacial structures and processing stability of surimi particles-konjac glucomannan complexes stabilized pickering emulsions via one-step and layer-by-layer

Abstract

Pickering emulsions fabricated by tailoring protein-polysaccharide complexes have attracted increasing attention. In this study, surimi particles (SPs) and konjac glucomannan (KGM) were utilized to prepare Pickering emulsions via one-step or layer-by-layer methods. Firstly, SPs and SPs-KGM particles were prepared and characterized, then the interfacial structures and stability including storage, heating, freeze-thawing (FT) of Pickering emulsions were determined. Results showed that introduction of KGM could not cause phase separation of the SPs suspension (aqueous phase) within 24 h at 4 °C, which might relate to the entanglement structures, hydrogen bonding and weak charge repulsions between SPs and KGM. According to microstructure images, the KGM with linear chains enabled SPs based Pickering emulsions possessing small droplets, and these droplets coated with a uniform and dense interface layer. Moreover, the KGM combined with SPs endowed both the Pickering emulsions and interfacial layers with superior viscoelastic properties. After 14 days of storage at 4 °C, the stability index of Pickering emulsions with SPs and KGM reached 100% regardless of the mixing methods. Unlike the poor stability of single SPs stabilized emulsions, the emulsions prepared with SPs and KGM remained comparatively stable under heating and FT conditions. In conclusion, the KGM improved the interfacial properties of SPs stabilized Pickering emulsions whether using one-step or layer-by-layer approach, further promoting the processing stability of these systems.