The Role of Processing Temperature in Flocculated Emulsions

Ecofriendly emulsions can suffer flocculation induced by processing. This destabilization mechanism could lead to a coalescence phenomenon with aging time. This work is based on tuning the preparation temperature of ecofriendly emulsions to reduce the flocculation. Bigger droplet sizes were shown for emulsions processed above 35 °C. Emulsions prepared up to 15 °C showed a crossover point in the mechanical spectra while a gel-type behavior was shown for emulsions processed above this temperature. This fact pointed out two different grades of flocculation. Emulsions with a high flocculation degree showed an increase of droplet size with aging time, which is related to coalescence. A combined analysis of complex viscosity, volumetric diameter, and backscattering with aging time demonstrated that the most stable emulsion was prepared at 5 °C since a reduction of both collision frequency and flocculation during the preparation occurred. This work demonstrated the direct relation between flocculation and processing temperature for these emulsions.