• Korean Journal of Agricultural Science
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• v.40 no.3
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• pp.227-235
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• 2013

This study was conducted to prove the effect of irradiation on lipases (lipase AK, lipase AH, lipase PS-D, Lipozyme TLIM, Lipozyme RMIM and Novozyme SP435) which were used for interesterification reaction using batch type reactor. Through such interesterification, structured lipid (1(3)-palmitoyl-2-oleoyl-3(1)-stearoyl, POS) was synthesized by lipase treated with irradiation at different doses (0, 3, 7, 14, 29 and 59 kGy) using canola oil, palmitic ethyl ester (PEE) and stearic ethyl ester (StEE). After the reaction, fatty acid composition of triacylglycerol (TAG) in structured lipid was analyzed to compare the lipase activity. The results showed that activity of the irradiated lipase AH, PS-D and Novozyme SP435 with certain dose (3 kGy) were slightly improved. Such change of lipase activity suggested that irradiation might affect on the interesterification properties. Especially, Lipase AK, Lipozyme TLIM and Lipozyme RMIM after at 3 kGy irradiation showed that content of stearic acid ($C_{18:0}$) was increased while palmitic acid ($C_{16:0}$) decreased in the interesterified products.

• Food Science and Preservation
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• v.16 no.2
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• pp.246-252
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• 2009

Diacylglycerol(DAG) was produced by enzymatic esterification of glyceryl mono-oleate(GMO) and conjugated linoleic acid(CLA) in a stirred-batch type reactor. The reaction was catalyzed by lipozyme RMIM(an immobilized lipase from Rizomucor miehei). DAG was isolated by a short-path distillation process and decolorized. DAG oil was composed of 87.3% DAG, 11.4% triacylglycerol(TAG), and 1.5% monoacylglycerol(MAG)(all w/w). Major fatty acids in DAG oil were oleic acid(54%), CLA(31.1%), and linoleic acid(7%). DAG oil iodine,and acid values were 108.8, 2.57, and 1, respectively. The DAG oil solid fat index(SFI) and thermograms were obtained using differential scanning calorimetry.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1559-1563
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• 2009

Scaled-up production of oil containing diacylglycerol (DAG), so called diacylglycerol-oil, was produced by lipase-catalyzed reaction. Mixture of soybean oil and glyceryl monooleate with 1:2 molar ratio was esterified with Lipozyme RMIM in a batch-type reactor at 55$^{\circ}C$ and 300 rpm during 6 hr. After short-path distillation for removal of monoacylglycerol and free fatty acid as reaction by-products, diacylglycerol-oil mainly consisted of DAG (29 area%) and TAG (71 area%). The major compositional fatty acids in diacylglycerol-oil were oleic (44.36 wt%), and linoleic acids (37.36 wt%). Acid value and iodine value of diacylglycerol-oil were 0.13 and 112.6, respectively. Solid fat content (SFC) of diacylglycerol-oil was observed after differential scanning calorimetry (DSC) analysis in which three melting peaks at -25.0, 0.1, and 11.2$^{\circ}C$ were shown.

• Korean Journal of Agricultural Science
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• v.41 no.2
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• pp.141-147
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• 2014

Diacylglycerol-oil (DAG oil) and four kinds of fatty acids [C16:0, C18:0, perillar oil-hydrolyzate(C18:3, 59.7%) and docosahexaenoic acid(DHA, C22:6, 63.7%)] were enzymatically esterified with 1:0.5, 1:1 and 1:1.5 molar ratio (DAG oil: fatty acids) to produce structured DAG. The reaction mixture were catalyzed by addition of sn-1,3 specific Lipozyme RMIM with 10 wt% of total substrates, and reacted for 1, 3, 6 and 24 hr at $62^{\circ}C$ with 220 rpm on the shaking water bath. The produced DAG were analyzed by TLC. In the result, the proportion of each fatty acid [(C16:0, C18:0, perilla oil-hydrolysate(C18:3, 59.7%) and DHA(C22:6, 63.7%)] on DAG products were increased as molar ratios of substrate increased. Among them, DHA showed the least reaction rate in which 24.2 % of DHA was found in the structured DAG molecules after 24 hr reaction with 1:1.5 molar substrate amount ratio.

• Food Science of Animal Resources
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• v.37 no.6
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• pp.813-822
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• 2017

The aim of this study was to prepare diacylglycerol (DAG) by enzymatic glycerolysis of lard. The effects of reaction parameters such as lipase type, reaction temperature, enzyme amount, substrate molar ratio (lard/glycerol), reaction time, and magnetic stirring speed were investigated. Lipozyme RMIM was found to be a more active biocatalyst than Novozym 435, and the optimal reaction conditions were 14:100 (W/W) of enzyme to lard substrate ratio, 1:1 of lard to glycerol molar ratio, and 500 rpm magnetic stirring speed. The reaction mixture was first incubated at $65^{\circ}C$ for 2 h and then transferred to $45^{\circ}C$ for 8 h. At the optimum reaction conditions, the conversion rate of triacylglycerol (TAG) and the content of DAG in the reaction mixture reached 76.26% and 61.76%, respectively, and the DAG content in purified glycerolized lard was 82.03% by molecular distillation. The distribution of fatty acids and Fourier transform infrared spectra in glycerolized lard samples were similar to those in lard samples. The results revealed that enzymatic glycerolysis and molecular distillation can be used to prepare more highly purified DAG from lard.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.6
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• pp.842-853
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• 2014

For developing indigestible lipids, symmetric triacylglycerol (ST) and asymmetric triacylglycerol (AT) were produced by enzymatic interesterification using high oleic sunflower oil, palmitic ethyl ester, and stearic ethyl ester in a shaking water bath. Used enzymes were Lipozyme RMIM for ST and Lipozyme TLIM for AT. To remove ethyl ester from reactants, methanol fractionation (reactant : methanol=1:5, w/v, $25^{\circ}C$) and florisil separation (reactant : florisil=1:8, w/w) were applied. Acetone fractionation (reactant : acetone=1:9, w/v) was implemented to separate triacylglcerol (TAG) species into ST and AT. Fractions I (before fractionation), II (after fractionation, liquid phase) and III (after fractionation, solid phase) were separated from ST, whereas fractions IV (after 1st fractionation, liquid phase) and V (after 2nd fractionation, solid phase) were from AT. From sn-2 fatty acid composition analysis, the sum of palmitic acid (C16:0) and stearic acid (C18:0) was 4.9~6.5 area% in ST (I, II, III), and 41.9~43.9 area% in AT (IV, V). In vitro digestion was performed for 0, 15, 30, 60, and 120 minutes at $37^{\circ}C$ in a shaking water bath. For the digestion results, hydrolysis of V was only 40% compared to others (I, II, III, IV) at 120 minutes due to its melting point ($49^{\circ}C$). However, initially (15 minutes), hydrolysis (%) was as follows: V$32.5^{\circ}C$, $31.8^{\circ}C$) and different slip melting points ($31.3^{\circ}C$, $19.5^{\circ}C$). Even though IV has a lower TAG content composed of two saturated fatty acids than III, it had a similar melting point.