Seung In Hong

Impact of Roasting on the Chemical Composition and Oxidative Stability of Perilla Oil

The impact of roasting was observed with regard to certain changes in the chemical components and oxidative stability of oil expelled from the roasted perilla seeds. The roasting times were established differently at each roasting temperature of 180, 200, and 220 °C. Trans fatty acids in perilla oil were detected, and the level detected increased as the roasting time increased. Moreover, the roasting of perilla seed led to an increase of 4 tocopherols, α-, β-, γ-, and δ-tocopherol, as well as phosphorus in the oil. The oxidative stability of the oils obtained after roasting increased during 60 d of storage at 60 °C. The rate of decrease of tocopherol in the oil from unroasted perilla seed was faster than that of the tocopherol in the oils from roasted perilla seeds during storage.

Lipase-Catalyzed Production of Pinolenic Acid Concentrate from Pine Nut Oil Using a Recirculating Packed Bed Reactor

Pinolenic acid (PLA) concentrate in fatty acid ethyl ester (FAEE) was efficiently produced from pine nut oil via lipase-catalyzed ethanolysis using a recirculating packed bed reactor (RPBR). The effects of reaction temperature, molar ratio, and residence time on the concentration of PLA were explored. Novozym 435 lipase from Candida antarctica showed less selectivity toward PLA esterified at the sn-3 position when temperature was increased from 45 to 55 °C. For the trials of molar ratio between 1: 50 and 1: 100 (pine nut oil to ethanol), there were no significant differences in the yield of PLA. Residence time of substrate in a RPBR affected significantly the PLA content as well as the yield of PLA. Optimal temperature, molar ratio (pine nut oil to ethanol), and residence time for production of PLA concentrate via lipase-catalyzed ethanolysis in a RPBR were 45 °C, 1: 50, and 3 min, respectively. Under these conditions, the maximal PLA content (36.1 mol%) in the concentrate was obtained during the initial 10 min of reaction.

Lipase-catalysed production of triacylglycerols enriched in pinolenic acid at the sn-2 position from pine nut oil

BACKGROUND The purpose of this study was to produce triacylglycerols (TAGs) enriched in pinolenic acid (PLA) at the sn-2 position using the principle of acyl migration, from the pine nut oil containing PLA esterified exclusively at the sn-3 position. RESULTS Two types of lipase-catalysed reactions, i.e. redistribution and reesterification of fatty acids, were successively performed using seven commercially available lipases as biocatalysts. Of the lipases tested, Novozym 435 and Lipozyme TL IM were effective biocatalysts for positioning PLA at the sn-2 location. These biocatalysts were selected for further evaluation of the effects of reaction parameters, such as temperature and water content on the migration of PLA residues to the sn-2 position and TAG content. For both lipases, a significant decrease in TAG content was observed after the lipase-catalysed redistribution of fatty acids for both lipases. The reduced TAG content could be enhanced up to approx. 92%, through lipase-catalysed re-esterification of the hydrolysed fatty acids under vacuum. CONCLUSION TAG enriched in PLA at the sn-2 position was synthesised from pine nut oil via lipase-catalysed redistribution and re-esterification of fatty acid residues using Lipozyme TL IM and Novozym 435 as biocatalysts.

Synthesis of monoacylglycerol containing pinolenic acid via stepwise esterification using a cold active lipase.

High purity monoacylglycerol (MAG) containing pinolenic acid was synthesized via stepwise esterification of glycerol and fatty acids from pine nut oil using a cold active lipase from Penicillium camembertii as a biocatalyst. Effects of temperature, molar ratio, water content, enzyme loading, and vacuum on the synthesis of MAG by lipase‐catalyzed esterification of glycerol and fatty acid from pine nut oil were investigated. Diacylglycerol (DAG) as well as MAG increased significantly when temperature was increased from 20 to 40°C. At a molar ratio of 1:1, MAG content decreased because of the significant increase in DAG content. Water has a profound influence on both MAG and DAG content through the entire course of reaction. The reaction rate increased significantly as enzyme loading increased up to 600 units. Vacuum was an effective method to reduce DAG content. The optimum temperature, molar ratio, water content, enzyme loading, vacuum, and reaction time were 20°C, 1:5 (fatty acid to glycerol), 2%, 600 units, 5 torr, and 24 h, respectively. MAG content further increased via lipase‐catalyzed second step esterification at subzero temperature. P. camembertii lipase exhibited esterification activity up to −30°C.

Enrichment of pinolenic acid from pine nut oil via lipase-catalyzed ethanolysis with an immobilized Candida antarctica lipase

Abstract Pinolenic acid (PLA) enrichment as an ethyl ester from pine nut oil was successfully accomplished in a batch reactor by lipase-catalyzed ethanolysis using Novozym 435 lipase from Candida antarctica as a biocatalyst. PLA is predominantly an sn-3 substituent of the pine nut oil triacylglycerol (TAG), where it accounts for about 39 mol% of the fatty acids esterified at that position. In the presence of ethanol, Novozym 435 exhibited sn-3 regiospecificity with respect to the TAG of pine nut oil. The effect of the molar ratio of reactants on PLA enrichment by ethanolysis was investigated. The molar ratios of pine nut oil to ethanol were varied from 1:20 to 1:100. A fatty acid ethyl ester (FAEE) fraction with higher PLA content was obtained in the early stage of the reaction, although the yield of PLA was small. However, the PLA content of the FAEEs decreased with increasing reaction time, while the yield of PLA increased. The molar ratio of pine nut oil to ethanol that produced the optimum content and yield of PLA in FAEEs was 1:80.

Lipase-Catalyzed Interesterification in Packed Bed Reactor Using 2 Different Temperatures

Lipase-catalyzed interesterification of high oleic sunflower oil and fully hydrogenated soybean oil (70 : 30, wt/ wt) was carried out in a packed bed reactor using an immobilized lipase from Thermomyces lanuginosus (Lipozyme TL IM) and the effect of a stepwise temperature protocol involving the 2 different temperatures, 60 and 70 °C, was investigated. The melting point of a fat that was incubated at 70 °C for 9 min was 57 °C, which suggested that it should be to employ a lower reaction temperature of 60 °C, after the first 9 min of the reaction. There were no significant differences (P < 0.05) in the conversion degree, triacylglycerol profile, and solid fat content between a constant temperature protocol (70 °C) and a stepwise temperature protocol (a combination of 70 and 60 °C). After 50 cycles, the overall residual activities of enzymes employed in stepwise temperature protocol were significantly (P < 0.05) higher than those of enzymes employed in constant temperature protocol.