TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: The feedstock is treated with the lipase in the presence of the lower alkyl alcohol to produce a first alkyl fatty acid ester mixture which is then reacted with the lower alkyl alcohol in the presence of the acid catalyst to produce a second alkyl fatty acid ester mixture which is suitable for use as a fuel and/or lubricant. The reaction to produce the first alkyl fatty acid ester mixture is carried out for a time period of 30-90 (preferably 60) minutes, at a temperature of 30-70 (preferably 50) degrees C. The process further involves separating the first alkyl fatty acid ester mixture from solid material by centrifugation. The reaction to produce the second alkyl fatty acid mixture is carried out under continuous reactive distillation conditions, at a temperature of 110-180 (preferably 125-165) degrees C. The unreacted lower alkyl alcohol that is distilled from the reaction is returned to the reaction mixture. The second alkyl fatty acid ester mixture is distilled from the reaction mixture and the distilled second alkyl fatty acid ester mixture is treated by gravity separation to remove unreacted glycerine. The pH of the second alkyl fatty acid ester mixture is adjusted to 6-8 (preferably 7) by adding an agent selected from potassium hydroxide, sodium hydroxide, magnesium hydroxide, ammonia, and calcium hydroxide (preferably magnesium hydroxide). The second alkyl fatty acid ester mixture is filtered to remove suspended solids or treated with a filtering agent. The filtering agent is separated from the second alkyl fatty acid ester mixture by mechanical filtration. The process further involves reacting rice bran oil with a lower alkyl alcohol (preferably n-butanol) in the presence of methane sulfonic acid to form a rice bran oil ester mixture; and mixing the rice bran oil ester mixture with the second alkyl fatty acid ester mixture to form an alkyl fatty acid ester mixture. The n-butanol is formed by enzymatic hydrolysis of a glycerine and soap mixture that is formed during the production of the second alkyl fatty acid mixture. The rice bran oil ester mixture is separated from solid material by centrifugation prior to mixing with the second alkyl fatty acid mixture. The ratio of n-butanol to rice bran oil in the starting reaction mixture is 1:3-1:4 (preferably 1:3.5). The ratio of methane sulfonic acid to n-butanol in the starting reaction mixture is 1:40-1:50. Preferred Components: The lipase is selected from a latex lipase and a plant lipase (preferably rice bran lipase) from a high lipid content grain, legume or seed. The lipase is a combination of a latex lipase and a plant lipase. The latex lipase is a papaya latex lipase. The papaya latex lipase is immobilized on a substrate formed from sucrose and lignite. The substrate is a pyrolised mixture of a saccharide and an acid precipitate from an alkaline extract of lignite. The feedstock is a plant oil or animal fat (preferably tallow). The lower alkyl alcohol is selected from methanol, ethanol, n-propanol, iso-propanol, n-butanol, s-butanol, and t-butanol (preferably ethanol). The ratio of papaya latex lipase to feedstock is 1:10-1:30 (preferably 1:20). The acid catalyst is a mineral acid (preferably sulfuric acid). The filtering agent is selected from diatomaceous earth, activated charcoal, and silicates. The silicate is selected from aluminosilicates and magnesium silicates (preferably magnesium silicate). EXAMPLE - No suitable example is given.