A mixture of low erucic acid rapeseed (LEAR) oil and tallow (6:4, w/w) was used for enzymatic interesterification using Lipozyme IM – a sn‐1,3‐specific lipase of Rhizomucor miehei, or for chemical interesterification using sodium methoxide. The starting mixture and the products of interesterification were separated by column chromatography into pure triacylglycerols (TAGs) and a non‐TAG fraction containing free fatty acids, mono‐ and diacylglycerols. Subsequently, the starting mixture, the products of chemical and enzymatic interesterification and the pure triacylglycerols were oxidized and their oxidative stability was examined by means of DSC. The investigation showed that the pure triacylglycerols isolated from the product of enzymatic interesterification have a comparable oxidative stability to that of the TAGs prepared from the starting mixture. In contrast, the TAGs obtained from the products of chemical interesterification had inferior oxidative stability. The presence of non‐TAG fraction in the interesterification products lowers their resistance to oxidation. The starting mixture had the highest oxidative stability.

Low‐calorie structured lipids (SL) containing behenic and oleic acids were prepared using interesterification of olive oil with hydrogenated high erucic acid rapeseed oil and acidolysis of olive oil with behenic acid. The reactions were catalyzed by the Lipozyme RM IM enzyme. Triacylglycerols (TAGs), obtained by interesterification (TAG SLHE ), contained 20.9 and 45.3% of behenic and oleic acids, respectively, whereas those obtained by acidolysis (TAG SLB ) contained 34.6 and 49.6% of these acids, respectively. In both cases, behenic acid was mainly incorporated in the sn‐1,3 positions of the TAG molecules (∼93%). The distribution of oleic acid in the individual positions was different for each product. The content of oleic acid in the sn‐2 position of TAG was 50.2 and 80.3% for TAGSLHEand TAGSLB, respectively. The melting temperature of TAGSLHE(45.5%) was higher than that of TAGSLB(37.5%). Because of the suitable solid fat content characteristics of TAGSLBas a function of temperature, it is possible to use TAGSLBin bakery and in confectionery industries for production of margarines and blends, among others.

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Enzymatic acidolysis of rapeseed oil with capric acid was carried out to obtain structured lipids. The reaction was catalyzed by Lipozyme IM lipase from Rhizomucor miehei. I I e enzyme preparations contained 2.8 and 10% water. The reaction conditions were enzyme load of 8% (w/w total substrates), substrate mole ratio of 1:6 (rapeseed oi1:capric acid), and reaction temperature of 65C. The results showed that triacylglycerols (TAG) after transesterification contained mainly oleic, linoleic and linolenic acids (about 90%) in the internal sn-2 position, whereas capric acid was mostly in the external sn-1,3 positions (approximately 40%). The quantity of water in the reaction medium had a significant influence on the yield and quality ofthe TAGfraction.