Reduced calorie emulsion-based foods: Protein microparticles and dietary fiber as fat replacers

- Whey protein microparticles can replace fat droplets in reduced calorie products.
- These microparticles increase viscosity and lightness of food emulsions.
- Digestible and indigestible polysaccharides can increase viscosity of reduced fat products.
- Protein microparticles with low calorie count and added healthy benefit have potential use in reduced-calorie foods.

The potential of using microparticulated whey protein (MWP) in combination with either modified starch or locust bean gum (LBG) as fat mimetics to fabricate reduced calorie emulsion-based sauces and dressings was studied. The influence of food matrix composition (protein, polysaccharide, and fat content), ionic strength, and pH on the properties of thermally processed model emulsions (90 °C/10 min) was investigated. Increasing protein concentration (2.5-7.5%) increased the mean (d3,2) particle diameter due to the formation of large protein aggregates. All MWP-containing systems had a creamy white appearance with high lightness (L* > 75). Addition of fat droplets (5%) further increased their lightness (L* > 90) due to enhanced light scattering. Addition of starch, LBG, or MWP increased emulsion viscosity due to the increased effective volume fraction of the dispersed phase. Addition of calcium chloride (10 mM) and pH adjustment (2-8) caused little change in the physicochemical properties of the mixed systems. Overall, the appearance and rheological properties of the mixed systems were similar to commercial sauces and dressings. This study demonstrates that reduced calorie food emulsions with appearance and consistency similar to those of full-fat versions can be formulated using protein microparticles and polysaccharides.