Effects of Soy Proteins and Hydrolysates on Fat Globule Coalescence and Whipping Properties of Recombined Low-Fat Whipped Cream

The interaction and synergetic effect of soy protein isolate (SPI) and its hydrolysates with different concentrations of monoglycerides were explored at the air-water/oil interfaces in recombined low-fat whipped cream (20%). The creams were made with 20% palm oil, 18% carbohydrate, 0.22% stabilizers, and 0.25-1.00% monoglycerides. The proteins used were native soy protein isolate (NSPI), commercial soy protein isolate (CSPI), soy protein hydrolysates by pepsin (SPHPe), soy protein hydrolysates by papain (SPHPa), and SC (sodium caseinate). Overrun, stability, rheological behavior, and texture of recombined low-fat whipped cream were studied. Results indicated that increasing concentration of monoglycerides was effective in improving the textural, whipping properties, and stability of recombined low-fat whipped cream. Increasing concentration of monoglycerides in the mix prompted the displacement of adsorbed protein from fat globules, built up a firmer structure of fat aggregates, and stabilized the trapped air bubbles in the structure of recombined low-fat whipped cream. At the same level of monoglycerides, SPHPa whipped cream produced a similar overrun, stability, and texture as SC. Due to the high proportion of beta-conglycinin in SPHPe, a low degree of fat globule partial coalescence occurred and led to low overrun and weakened structure in recombined low-fat whipped cream.