Comparison between enzymatic and chemical interesterification of high oleic sunflower oil and fully hydrogenated soybean oil

Structured lipids (SL) were prepared by enzymatic interesterification (EI) and chemical interesterification (CI) of high oleic sunflower oil (HOSO), and fully hydrogenated soybean oil (FHSO) in a weight ratio of 50:50 w/w. The EI was catalyzed by the immobilized lipase Lipozyme TL IM (Thermomyces lanuginosus) free of organic solvents at a concentration of 7% w/w, 70 degrees C for 9h, and samples were collected for analysis at 3, 6, and 9h. The original blend and the reaction products were evaluated for fatty acid (FA) composition, triacylglycerols (TAG), solid fat content (SFC), thermal analysis, and regiospecific distribution of FA. The EI provided considerable rearrangement of triglycerides classes, with lower levels of trisatured and tri-unsaturated TAG, and higher levels of monoun- and diunsaturated TAG. The SL obtained by EI reduced SFC with a linear and wide melting range by thermal analysis, lowering the melting point. Lower acyl migration was observed in EI within 3h of reaction, with similar results between both techniques at the maximum reaction time. The SL obtained by EI may have wide applications in specialty fats for confectionery and bakery products. Practical Applications: SL via enzymatic catalysis have been the focus of considerable attention in food industry. We report in this study, the comparison between enzymatic and chemical interesterification of a fully hydrogenated vegetable oil, and high oleic vegetable oil. The results show that the enzymatic process with 3h of reaction time present more selectivity, lower acyl migration of sn-2 position of the unsaturated fatty acid, and better nutritional value, when compared with the chemical process. These SL were projected to have broad applications in foods, as bakery/confectionery fats, and as a crystallization additive for lipids. The enzymatic process with 3h of reaction time showed the advantage of selectivity for production of new TAG and lower acyl migration sn-2 position of the unsaturated fatty acid when compared with the other reaction times, evidenced by NMR 13C. These SL were projected to have broad applications in foods, as bakery/confectionery fats and as a crystallization additive for lipids.