TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Components: The triglyceride mixture comprises 80-99.5% triglyceride and 0.5-20 wt.% free fatty acids. Preferred Process: The triglyceride-rich phase is contacted with a heterogeneous esterification catalyst in a second reactor, under conditions suitable for esterification, to produce a second product stream. The dried first product stream is contacted with an amount of methanol of 3-40 wt.% of a total of the dried product stream and methanol. The method involves additional steps of: separating water and methanol from the second product stream to produce a dried second product stream; contacting the dried second product stream with methanol to produce a second methanol-rich phase and a second triglyceride-rich phase; and separating the second methanol-rich phase and recycling it to the second reactor. The method of esterification of free fatty acids in triglycerides with methanol involves: contacting heterogeneous esterification catalyst in a first reactor with a reaction mixture comprising methanol and a triglyceride mixture containing 70-99.8 wt.% triglycerides and 0.2-30 wt.% free fatty acids, under conditions suitable for esterification, to produce a first product stream; separating water and methanol from the first product stream to produce a dried first product stream; contacting the dried first product stream with a recycled mixture comprising methanol to produce a first methanol-rich phase and a first triglyceride-rich phase; separating the first methanol-rich phase and recycling it to the first reactor; contacting the first triglyceride-rich phase with a heterogeneous esterification catalyst in a second reactor to produce a second product stream; and separating the second product stream into a phase comprising methanol and a second triglyceride-rich phase, and recycling the phase comprising methanol to the contacting step. The final triglyceride phase is contacted with an alcohol in a third reactor under conditions suitable for transesterification. The method further involves contacting the second triglyceride-rich phase with methanol to produce a second methanol-rich phase and a final triglyceride phase; and separating the second methanol-rich phase and recycling it to the second reactor. EXAMPLE - To simulate a single-stage reactor product resulting from 95% conversion of 10 wt.% free fatty acid in 90 wt.% triglyceride, 100 parts (by weight) canola oil, 0.55 parts free fatty acid (oleic acid), 11 parts fatty acid methyl ester (methyl oleate) were mixed. No water was included to simulate prior evaporation of product water. Then 50 parts of methanol were added to this mixture. After shaking and settling, liquid samples were taken and analyzed by gas chromatography of the resultant methanol-rich (top) and oil-rich (bottom) phases. The ratio of free fatty acid in the methanol-rich phase to the free fatty acid in the oil-rich phase was 1.3/0.6, or 2.2, while the corresponding ratio of fatty acid methyl ester was 0.1/7.0, or 0.01. The extraction of a dried product stream with methanol removed undesired free fatty acid and recycling it contributed to production of the desired fatty acid methyl ester, and this was done without removing amounts of free fatty acid methyl ester from the product stream.