An exploration on coconut milk stability by protein characterization, sterilization controlling, and alternative...

Coconut milk with high fat-to-protein ratio often encounters physical instability. Characterization of coconut protein could provide better understanding of the roles protein played in stability. The results showed coconut protein predominantly consisted of 11S globulin (53 kDa cocosin with acidic and basic polypeptides linked by disulfide bonds) and 7S globulin (53, 35, and 24 kDa). The easier precipitation of 11S globulin indicated poor emulsifying property, thus partly resulted in instability of coconut milk. Atmospheric pressure sterilization or ultra-high temperature instantaneous sterilization greatly improved the stability of coconut milk, with average particle size of about 4 μm. Furthermore, soy protein isolate or sodium caseinate, as alternatives to Tween 80, significantly enhanced coconut milk stability. Notably, sodium caseinate promoted coconut aroma with high odor activity values of ethyl decanoate/octanoate. This study provided valuable insights into protein characterization, sterilization, and natural protein substitution, offering a theoretical basis for better development of coconut milk.