Abstract: The effects of the lipophilic emulsifiers glycerol monostearate (GMS), polyglycerol fatty acid esters (PGE) and propylene glycol monostearate (PGMS) on the crystallization of an anhydrous milk fat-based fat blend and the stability of whipped cream were studied. The purpose of this study was to establish the relationship between the crystallization of the fat blend and the stability of whipped cream in order to provide a theoretical basis for regulating the stability of whipped cream. Results demonstrated that GMS, having hydrophilic glyceryl groups, showed the highest onset crystallization temperature. GMS, as a heterogeneous nucleating facilitator, induced heterogeneous nucleation and led to the formation of tiny and homogenous crystals in the fat blend. Owing to the good emulsifying property of GMS, small and uniform fat globules were well dispersed in the emulsion. These crystals and fat globules contributed to the formation of a firm and compact foam structure in whipped cream. PGE, with hydrophilic polyglycerol groups, showed the largest spatial structure, which provided many nucleation sites to form small and uniform crystals in the fat blend during the crystallization process and finally strengthen the emulsifying stability and bubble stability of whipped cream. PGMS, containing hydrophilic propylene glycol groups and having good oil solubility, could easily adsorb onto the surface of the fat blend and induce heterogeneous nucleation. However, PGMS had low onset crystallization temperature, and the heterogeneous crystals formed by PGMS hindered the crystal growth of the fat blend and reduced the interaction between crystals. The tiny but loose network structure of crystals formed in the fat blend resulted in the formation of a weak foam structure in whipped cream.

Key words: hydrophilic group; lipophilic emulsifier; fat blend; whipped cream; stability