Experimental data for liquid–liquid equilibrium of fatty systems with emphasis on the distribution of tocopherols and tocotrienols

The present paper reports liquid–liquid equilibrium data for systems composed of degummed soybean oil + commercial linoleic acid + anhydrous ethanol, degummed soybean oil + commercial linoleic acid + ethanol + water, refined rice bran oil + commercial oleic acid + anhydrous ethanol and refined rice bran oil + commercial oleic acid + ethanol + water at 298.15 K, 313.15 K and 323.15 K. α, β, γ and δ tocopherol and tocotrienol contents in both phases were analyzed. The parameters of the NRTL model were adjusted to the experimental data. For higher temperatures and the free fatty acid contents, higher are distribution coefficients of tocopherols and tocotrienols, due to the increase in solubility among the systems components. In contrast, the distribution coefficients of tocopherols and tocotrienols decrease when water is added to ethanol, which represents the increase in retention of tocopherols and tocotrienols in the oil phase. The NRTL model represented well the experimental data, and the global deviations between calculated and experimental data were 1.02% and 0.95% for systems composed of degummed soybean oil and refined rice bran oil, respectively.