Although protein-polysaccharide complexes with different phase behaviors all show potential for stabilizing high
internal phase Pickering emulsions (HIPPEs), it is not clarified which aggregation state is more stable and age-
friendly. In this study, we investigated and compared the stability and age friendliness of HIPPEs stabilized with
egg yolk and carboxymethyl cellulose (EYCMC) in different phase behaviors. The results revealed differences in
particle size, aggregation state, charge potential, and stability of secondary and tertiary structures of EYCMC. The
behavior of EYCMC at the oil-water interface was mainly divided into three phases: rapid diffusion, permeation,
and reorganization. The electrostatic interaction, kinetic hindrance, and depletion attraction were the mecha-
nisms primarily involved in stabilizing HIPPEs by EYCMC. Rheological analysis results indicated that HIPPEs had
excellent viscoelasticity, structural recovery properties and yield stress. HIPPEs were used in 3D printing,
electronic nose testing, IDDSI testing and in vitro digestive simulations for the elderly, demonstrating a fine
appearance, safe consumption and bioaccessibility of β-carotene. Soluble complexes showed the best stability
and age friendliness compared to other aggregated forms. This study serves as a foundational source of infor-
mation for developing innovative foods utilizing HIPPEs.