Effect of pH-shifting and sonication-assisted treatment on properties and stability of vegetable oil-based whipped cream stabilized by kidney bean protein aggregates

Whipped cream stabilized by kidney bean protein aggregates (KPAgs) was constructed, and the effects of pH-shifting and sonication-assisted treatment on the structure of KPAgs and the properties and stability of the resulting whipped cream were invFestigated. The relationship between the properties and stability of whipped cream and the structure of KPAgs was analyzed. The visual appearance, ThT fluorescence, TEM, endogenous fluorescence and FT-IR results showed that KPAgs prepared at pH 2.0 had better gel properties than those at pH 4.5 and 7.0, because the former produced fibril aggregates while the latter two mainly produced particle aggregates. The CLSM results of the emulsion showed that the strength of the protein gel structure decreased with increasing pH during preparation, and gradually failed to form a continuous phase. Kidney bean protein was more suitable than soybean protein for preparing fibril protein aggregates suitable for whipped cream. The protein gel three-dimensional network structure of the kidney bean protein after sonication-assisted treatment was more compact because more KPAgs were generated. Protein fibril aggregates had a higher aspect ratio and structural flexibility than particle aggregates, and were easier to arrange on the interface to form an interface layer, thereby avoiding the aggregation of air bubbles and thus having better whipped cream structural stability.