Current status and challenges in heterogeneous catalysis for enzymatic free fatty acid remediation process of rice bran oil

Abstract: Rice bran oil has been regarded as nutritious and healthy oil, because of its balanced fatty acid profile, and richness in bioactive phytochemicals, such as oryzanol, tocopherols, tocotrienols, plant sterols and triacontahexaene. However, rice bran oil with high acid value usually means the issues such as high refining loss, high energy consumption, waste and loss of nutrient component etc. Enzymatic free fatty acid remediation process (EFFARP) has the advantages of mild reaction condition, high catalytic specificity, and environmental friendliness, and has been considered as the promising technology. Furthermore, heterogeneous catalysis is crucial for its durability, efficiency, and substantial reusability. This review deals with enzymatic refining of rice bran oil, overview of production processes of EFFARP, raw materials, reaction systems, acyl donors, lipases, mechanism of heterogeneous catalysis, factors influencing the esterification, problems associated with the current employed catalysts, and the effects of EFFARP on the composition, nutrient components, and antioxidant properties of rice bran oil. Meanwhile, the challenges of EFFARP for its industrial application was described, and countermeasures were proposed. This review suggests that EFFARP of rice bran oil looks promising.