Sunflower oil enriched with stearic and oleic acids could produce cocoa butter equivalents with higher melting points, according to new research published in Food Chemistry.
“The butters obtained by us displayed quite similar physical properties to conventional cocoa butter,” Joaquín Salas from the Instituto de la Grasa (CSIC), Spain, told CosmeticsDesign-Europ.com
“This means that at the corporal temperature they partially melt and can cover human skin with a thin film just like that butter.
"Moreover, this oil has the properties of any other refined sunflower oil, containing high levels of tocopherols that also protects the skin from oxidation as well as having low allergenicity,” Salas said.
Cocoa butters are valuable fats, extracted from the seeds of the Theobroma cacao tree. The scientists state that the tropical nature of cocoa butter, and susceptibility to pests, can make cocoa supply uncertain and variable.
Likewise, the rising price of cocoa butter has also increased interest in developing cheaper, more readily available alternatives.
Cocoa butter equivalents (CBEs) are fats with a similar composition and melting profile as cocoa butter, and are usually prepared by blending palm oil fractions and stearate-rich tropical butters.
But on top of the issue of price and the problems raising crops, it would also be of great commercial interest to source triglyceride (TAG) rich oils from reliable, sustainable sources – such as oil crops in temperate climates, rather than relying on palm oils and tropical butters.
The new study assessed the potential of high stearic and high oleic (HSHO) sunflower oils as a producer of CBEs.
Enriched sunflower oils were fractioned using solvents, to produce solid fractions that could be used in CBE formulations.
The research used 17 and 20 per cent stearic acid enrichments and studied properties of the oils and oil/solvent ratios. The resulting solids were isolated and chemically compared to CB and CBE sources like mango and shea butters, as well as also determining the melting intervals of the resulting fractions.
The authors found oils with different stearic acid contents produced similar stearins but at different yields depending on the initial TAG content.
They reported solid fractions containing between 65 and 80 per cent saturated-unsaturated-saturated (SUS) displayed properties similar to cocoa butter - consistent with the characteristics of CBEs.
Additionally, mixtures of sunflower CBE and CB were observed to be “fully compatible”, indicating they could be suitably used as cocoa butter equivalents.
Although the research has thus far mainly concentrated on the use of HSHO sunflower oils in food applications, the scientists say they have already been contacted by a leading ingredients player in the cosmetic and personal care segment and are now working towards creating samples for testing.
Source: Food Chemistry
Published online ahead of print, doi: 10.1016/j.foodchem.2010.06.053
“Production of stearate-rich butters by solvent fractionation of high stearic–high oleic sunflower oil”
Authors: J.J. Salas, M.A. Bootello, E. Martínez-Force, R. Garcés