ENZYMATIC ISOLATION AND ENRICHMENT OF ERUCIC ACID FROM HEA SEED OILS: CURRENT STATUS
Erucic acid (EA), a fatty acid of 22-carbon chain with one isolated double bond, has broad industrial applications. Currently, erucic acid is isolated from Crucifereae plant oils through steam splitting, namely the Colgate-Emery process, followed by fractional distillation. This two-step process involves drastic conditions, low energy efficiency, and extensive product degradation. Enzymatic approaches, on the other hand, have many advantages including mild operating conditions and high selectivities. To develop a more efficient alternative process, researchers have studied enzymatic approaches for EA isolation and enrichment for about two decades. Lipases have shown three types of specificities in catalyzing high-erucic-acid (HEA) oils, namely fatty-acid-specific, region-specific, and non-specific. With lipases of certain specificities, various processes of hydrolysis, esterification, interesterification, and transesterification have been studied. Research has also been conducted on investigating the effects of process parameters, including operating temperature, lipase content, and water content, on the process efficiency. The enzymatic approach has shown its potential in isolating and enriching EA from different Crucifereae seed oils. This article reviews the current status of the studies, especially the performance of different lipases and corresponding enzymatic reactions, for EA enrichment from Crucifereae plant oils.