Modulating physicochemical and interfacial properties of faba bean proteins under thermal treatment and pH shifting:...

Faba bean protein represents a promising source of plant-based protein with the potential to serve as a natural emulsifier in oil-in-water (O/W) emulsions. However, the emulsifying properties of native faba bean protein exhibit limitations. To enhance these, various modification techniques are essential to improve the functional performance of faba bean proteins. In this study, Faba bean protein isolate (FPI) was subjected to heat treatment (80 °C and 100 °C), pH shifting (pH 10 and 12), and a combined approach of both methods (100 °C and pH 10). The effects of these treatments on the physicochemical and interfacial properties of FPI, as well as the stability of FPI-stabilized oil-in-water emulsions were investigated. The results indicated that heat treatment, pH shifting, and combined heat treatment and pH shifting increased the solubility, surface hydrophobicity, and interfacial activity of FPI, with pH shifting having greater effects than heat treatment. In addition, the enhancement of emulsion stability through heat treatment was limited. Conversely, emulsions stabilized by pH-shifting and combined heat treatment and pH shifting treated FPI exhibited reductions in particle size, narrower particle size distributions, and improved creaming stability. Overall, the findings of this study provide valuable insights into the relationship between physicochemical and interfacial properties and the emulsion characteristics of FPI. The pH-shifting and combined heat treatment and pH shifting treated FPI showed promise as functional ingredients and potential emulsifiers and stabilizers in diverse emulsion systems and food applications.