peer reviewed | Partial coalescence influences to a great extent the properties of final food products such as ice cream and whipped toppings. In return, the partial coalescence occurrence and development are conditioned, in such systems, by the emulsion's intrinsic properties (e.g. solid fat content, fat crystal shape and size), formulation (e.g. protein content, surfactants presence) and extrinsic factors (e.g. cooling rate, shearing). A set of methods is available for partial coalescence investigation and quantification. These methods are critically reviewed in this paper, balancing the weaknesses of themethods in terms of structure alteration (for turbidity, dye dilution, etc.) and assumptions made for mathematical models (for particle size determination) with their advantages (good repeatability, high sensitivity, etc.).With the methods proposed in literature, the partial coalescence investigations can be conducted quantitatively and/or qualitatively. Good correlation were observed between some of the quantitative methods such as dye dilution, calorimetry, fat particle size;while a poor correlation was found in the case of solvent extraction method with other quantitativemethods. The most suitableway for partial coalescence quantification was implied to be the fat particle size method, which would give results with a high degree of confidence if used in combination with a microscopic technique for the confirmation of partial coalescence as the main destabilization mechanism.

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).