Formation and emulsification properties of self‐assembled potato protein microgel particles under different pH conditions

Summary This study evaluated the formation of potato protein microgel particles (PPM) formed by heating a protein solution at pH 2–8 in order to improve emulsifying potential of commercial potato protein (PP). The physicochemical properties (particle diameter, ζ‐potential and contact angle), structural characteristics and emulsifying capacity of PPM were investigated. The results indicated that preparation pH of PPM had significantly influenced the emulsification properties. The PPM samples prepared near the isoelectric point of PP (pI ~ 4.5) had low ζ‐potential, high particle size, lower emulsifying activity index (EAI) and emulsifying stability index (ESI). Meanwhile, compared to PP, PPM prepared at pH (pH = 2, pH = 6–8) stay away from isoelectric point had higher EAI and ESI, evidenced by the appropriate ζ‐potential and contact angel. In conclusion, PPM prepared at specific pH (pH = 6) would enhance the emulsifying properties of potato protein, the findings would broaden the application of potato protein in the food industry.