We designed Air-in-Oil-in-Water (A/O/W) emulsions. First, Air-in-Oil foams were fabricated by whipping anhydrous milk fat. The maximum overrun was obtained at 20 °C. The foams contained 30–35 vol% air and were stabilized solely by fat crystals. To refine the bubble size, foams were further sheared in a Couette’s cell. The average bubble size reached a value as small as 6.5 μm at a shear rate of 5250 s−1. The nonaqueous foams were then dispersed in a viscous aqueous phase containing sodium caseinate to obtain A/O/W emulsions. The shear rate was varied from 1000 to 7500 s−1, allowing to obtain Air-in-Oil globules whose average diameter ranged from 15 to 60 μm. To avoid globule creaming, the aqueous phase was gelled by incorporating hydroxyethyl cellulose. Homogeneous emulsions were obtained with fat globules containing around 22 vol% of residual air. The systems were kinetically stable for at least 3 weeks at 4 °C.

Food grade W/O microemulsions were developed and characterized to be used in blends with sunflower oil as replacers of palm kernel oil in whipped cream alternatives. Creams for whipping are oil-in-water (O/W) emulsions containing significant proportions of partially hydrogenated solid fat. With the addition of sunflower oil and W/O microemulsions up to 6.8% w/w in the final confectionary product we achieved the decrease of saturated fats and also the decrease of the energy required for the formulation. More specifically, by replacing 20% w/w of the oil phase by the proposed edible W/O microemulsions, the homogenization time was reduced from 7 to 5min under the same experimental conditions. In addition solid fat partial replacement permitted the modification of structural and textural characteristics. Droplet size and size distribution measurements were performed using dynamic light scattering (DLS). The existence of rather polydisperse oil droplets with diameters of approximately 1μm upon palm kernel oil partial replacement was detected. Structural characterization of the proposed alternative systems with confocal laser scanning microscopy (CLSM) showed the existence of air bubbles of diameter 6–94μm stabilized by globular oil droplets having diameters ranging from 4.2 to 5.9μm adhered to their surface. Firmness and consistency of the proposed alternative formulations were evaluated using a Stevens-texture analyzer. As a result emulsions after whipping gave products with lower density (362±9g/mL) but higher consistency (208±7g) as compared to the standard whipped cream preparation (150±5g).