Development of structured W/O emulsions with the use of only candelilla wax

Abstract

We investigated the development of water‐in‐oil (W/O) emulsions using only candelilla wax (CW), evaluating the effects of different water to CW oleogel ratios (40:60, 50:50, 60:40) and the CW concentration (0.75% to 3%). The emulsions were developed by shearing the systems with an ultra‐turrax type homogenizer (60 s at 25°C) at the different water to CW oleogel ratios. After 0 and 20 days of storage (25°C) the emulsions were evaluated through microscopy, rheology, water droplet diameter, emulsion stability, and x‐ray diffraction measurements. The results showed that at all water to CW oleogel ratios the surface‐active components of the CW (i.e., triterpenic alcohols, aliphatic alcohols, and fatty acids) stabilized the oil–water interface, while the n‐alkanes and long chain esters formed an oleogel in the oil phase. Independent of the storage time, all the CW emulsions showed frequency independent rheological behavior. However, after applying a strain within the plastic region the 40:60 and 50:50 emulsions formulated with 1.5% to 3% CW provided the higher elasticity and emulsion stability, even after two freeze‐thaw cycles. In particular, the 40:60 and 50:50 emulsions with 1.5% CW had a recovery profile similar to commercial mayonnaise. In contrast, independent of the CW concentration, the 60:40 emulsions showed the lowest recovery profile and highest emulsion instability. These results showed the CW as a multifunctional material capable to develop structured W/O emulsions at room temperature without adding surfactants. The structured W/O emulsions developed by CW could be useful in the formulation of trans‐free, stable low‐fat edible spreads.