TECHNOLOGY FOCUS - BIOLOGY - Preferred Components: The source oil is derived from plant materials; or derived from one of castor bean plant materials, camelina plant materials, palm plant materials, legume plant materials, Lesquerella species plant materials, Brassica species plant materials, and Brassicacea plant materials. The plant materials are derived from genetically modified plants.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Prepared Process: The recovered non-hydroxy fatty acid methyl esters are washed with a short-chain alcohol to separate therefrom additional hydroxyl fatty acid methyl esters, and separately recovering the washed non-hydroxy fatty acid methyl esters and the additional hydroxy fatty acid methyl esters. The non-hydroxy fatty acid methyl esters are comingled with an organic solvent comprising urea, thus creating mixture of: saturated non-hydroxy fatty acid methyl esters complexed with urea and free unsaturated non-hydroxy fatty acid methyl esters, and separately recovering the saturated non-hydroxy fatty acid methyl esters complexed with urea and the free unsaturated non-hydroxy fatty acid methyl esters. Preferred Components: The short-chain alcohol is one of methanol, ethanol and propanol (preferably methanol). The pentane/hexane is methylpentane/hexane. The organic solvent comprises a short-chain alcohol (preferably 1-3C alcohol). The free unsaturated non-hydroxy fatty acid methyl esters are suitable for use as a cold-tolerant biodiesel. EXAMPLE - Castor oil was dried under vacuum for 30 minutes at 100 degrees C and then cooled to 60 degrees C. Dried potassium hydroxide (KOH) (2 wt./wt.% of oil weight) was dissolved in methanol (20 wt./wt.% of oil weight) in a beaker. Once the oil was cooled to 60 degrees C, the KOH/methanol mixture was added to the oil. The mixture was mixed in the rotary evaporator for 4 hours. Then, the mixture was transferred into a funnel for phase separation. The top layer comprised of castor oil methyl esters. The bottom layer was recovered and discarded. The top layer was transferred to a beaker and heated to 60 degrees C under nitrogen after which, a soap analysis was then done on the heated top layer. Then, Trysil S615 (RTM: silica hydrogel) was added to the heated top layer (1 wt./wt.% Trysil S615 per 1000 parts per million (ppm) of soap) followed by mixing for 15 minutes before filtering to recover and separate the residual soap from the castor oil methyl esters. The castor oil methyl ester fraction, comprising hydroxy fatty acid methyl ester (HFAME) and non-hydroxy fatty acid methyl ester (NHFAME) was then dried under vacuum and stored for subsequent use as the starting material in the HFAME purification process. In a separatory funnel, castor oil methyl esters (10 g) were mixed with a mixture containing 80% methanol (200 g) and methylpentane/hexane mixture (50 g) to obtain a ratio of 1:20:5 (wt./wt./wt.; methyl esters:80% methanol:methylpentane/hexane). The mixture was shaken vigorously for 30 seconds and then allowed to separate into two layers. The NHFAME separated into the top layer while the HFAME separated into the bottom layer. The layers were separated and desolventized to obtain enriched NHFAME and HFAME fractions.