• Korean Journal of Food Science and Technology
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• v.38 no.1
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• pp.16-21
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• 2006

Effect of heat (160, 190, and $220^{\circ}C$ for 24 hr) on coconut oil was examined by principal component analysis using electronic nose consisting of six metal oxide sensors. Increase in heating temperature decreased ratio of resistance and first principal component score (from +0.952 to -0.325), indicating rancidity of coconut oil increased at high heating temperature. Result of electronic nose based on GC with surface acoustic wave sensor showed significant changes in volatile profiles of coconut oil. High resolution olfactory imaging $(VaporPrint^{TM})$ was particularly useful for evaluating oil quality. Peak numbers and areas increased with increasing heating time and temperature (160, $220^{\circ}C$). Electronic nose analysis can provide simple, fast, and straightforward results and is best suited for quality control and process monitoring in flavor field of food industry.

• Journal of Electrical Engineering and Technology
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• v.11 no.3
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• pp.690-698
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• 2016

In this paper, a study is carried out to investigate the dielectric, physical and chemical properties of Palm Oil (PO) and Coconut Oil (CO) under open thermal ageing condition. The type of PO used in this study is Refined Bleached and Deodorized Palm Oil (RBDPO) Olein. The ageing experiment was carried out at 85 ℃ and 115 ℃ for 1, 3, 5, 7 and 14 days. Several parameters were measured such as AC breakdown voltage, dielectric dissipation factor, relative permittivity, resistivity, viscosity, moisture and acidity throughout the ageing duration. Based on the study, it is found that there are no significant changes on the AC breakdown voltages and relative permittivities for both RBDPO and CO. At ageing temperature of 115℃, there are clear reduction trends of dielectric dissipation factor for CO and resistivities for most of RBDPO. On the other hand, no clear trends are observed for viscosities, moisture and acidities of RBDPO and CO throughout the ageing duration.

• Applied Chemistry for Engineering
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• v.30 no.5
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• pp.530-535
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• 2019

In this study, an optimization for the emulsification process with coconut oil and sugar ester was performed in conjunction with the central composite design (CCD) model of response surface methodology (RSM). Response values for the CCD model were the viscosity of the emulsion, mean droplet size, and emulsion stability index (ESI) after 7days from the reaction. On the other hand, the emulsification time, emulsification rate, and amount of emulsifier were selected as quantitative factors. According to the result of CCD, optimum conditions for the emulsification were as follows; the emulsification time of 22.63 min, emulsification speed of 6,627.41 rpm, and amount of emulsifier of 2.29 wt.%. Under these conditions, the viscosity, mean droplet size, and emulsion stability index (ESI) after 7 days from reaction were estimated as 1,707.56 cP, 1877.05 nm, and 93.23%, respectively. The comprehensive satisfaction of the CCD was indicated as 0.8848 with an average error of $1.2{\pm}0.1%$ from the experiment compared to that of the theoretical one. Overall, a very low error rate could be obtained when the central composite model was applied to the optimized coconut oil to water emulsification.

• Korean Chemical Engineering Research
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• v.56 no.2
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• pp.275-280
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• 2018

Methyl ester derived from coconut oil is very interesting to study since it contains free-fatty acid with chemical structure of medium carbon chain ($C_{12}-C_{14}$), so the methyl ester obtained from its part can be a biodiesel and another partially into biokerosene. The use of heterogeneous catalysts in the production of methyl ester requires severe conditions (high pressure and high temperature), while at low temperature and atmospheric conditions, yield of methyl ester is relatively very low. By using microwave irradiation trans-esterification reaction with heterogeneous catalysts, it is expected to be much faster and can give higher yields. Therefore, we studied the production of methyl ester from coconut oil using CaO catalyst assisted by microwave. Our aim was to find a kinetic model of methyl ester production through a transesterification process from coconut oil assisted by microwave using heterogeneous CaO catalyst. The experimental apparatus consisted of a batch reactor placed in a microwave oven equipped with a condenser, stirrer and temperature controllers. Batch process was conducted at atmospheric pressure with a variation of CaO catalyst concentration (0.5; 1.0; 1.5; 2.0, 2.5%) and microwave power (100, 264 and 400 W). In general, the production process of methyl esters by heterogeneous catalyst will obtain three layers, wherein the first layer is the product of methyl ester, the second layer is glycerol and the third layer is the catalyst. The experimental results show that the yield of methyl ester increases along with the increase of microwave power, catalyst concentration and reaction time. Kinetic model of methyl ester production can be represented by the following equation: $-r_{TG}=1.7{\cdot}10^6{_e}{\frac{-43.86}{RT}}C_{TG}$.

• Journal of the Korean Applied Science and Technology
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• v.34 no.4
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• pp.1058-1065
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• 2017

Amino acid based surfactants as protein-surfactants is eco-friendly compound. So, amino acid based surfactants is expected as next generation surfactants. Amino acid based surfactants has high biodegradability, low toxicity and surface active properties. In this experiment, amino acid based surfactants, cocoyl glycine, was synthesized by glycine and triglyceride such as coconut oil and palm oil. And it was tested the surface tension, emulsifying properties, foam stability and HLB value. The synthesized surfactants was confirmed by FT-IR. Surface tension of surfactants synthesized by coconut oil on diluted aqueous solutions of surfactants was 31.2 dyne/cm at $1.0{\times}10^{-4}mol/L$. Surface tension of surfactants synthesized by palm oil on the diluted aqueous solutions of surfactants was 42.1 dyne/cm at $3.2{\times}10^{-5}mol/L$. Foam stability measured the foam height as time passed. Initial foam height of surfactants synthesized by coconut oil is 14.5 cm, and 10.7 cm after five minutes. Initial foam height of surfactants synthesized by palm oil is 3.0 cm, and 2.8 cm after five minutes. Foam height of surfactants synthesized by coconut oil was higher than surfactants synthesized by palm oil. But foam stability of surfactants synthesized by palm oil was better than surfactants synthesized by coconut oil. The emulsifying properties of synthesized surfactants are observed in benzene and soybean oil and emulsifying properties in organic solvent is better than in soybean oil.

• Journal of the Korean Applied Science and Technology
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• v.10 no.1
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• pp.39-47
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• 1993

This study was performed observe the effect of vegetable oil on the liver of 0.5% cholesterol-fed rats. In this experiment, male rats of Sprague-Dawley strain were used. The rats were divided into 5groups which were fed differently either for 8 weeks: basal diet, 20% sunflower oil diet, 20% soybean oil diet, 20% rapeseed oil diet.,20% coconut oil diet. The total cholesterol, triglyceride level in the liver were showed tendency of increase with increasing of P/S ratios. Bile acid excretion in the fecal increased with increasing of P/S ratios. The value of TBA in the serum and liver were increased in proportion to the amount of polyunsaturated fatty acid. The liver fatty acid of coconut-fed group showed larger variation than fatty acid of the cocount oil. The fat chang of sunflower oil diet in the liver showed the largest change.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1522-1528
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• 2008

The morphogenetic behavior of a tropical marine Yarrowia lipolytica strain on hydrophobic substrates was studied. Media containing coconut oil or palm kernel oil (rich in lauric and myristic acids) prepared in distilled water or seawater at a neutral pH supported 95% of the cells to undergo a transition from the yeast form to the mycelium form. With potassium laurate, 51 % of the cells were in the mycelium form, whereas with myristate, 32% were in the mycelium form. However, combinations of these two fatty acids in proportions that are present in coconut oil or palm kernel oil enhanced the mycelium formation to 65%. The culture also produced extracellular lipases during the morphogenetic change. The yeast cells were found to attach to the large droplets of the hydrophobic substrates during the transition, while the mycelia were associated with the aqueous phase. The alkane-grown yeast partitioned more efficiently in the hydrophobic phases when compared with the coconut oil-grown mycelia. A fatty acid analysis of the mycelial form revealed the presence of lauric acid in addition to the long-chain saturated and unsaturated fatty acids observed in the yeast form. The mycelia underwent a rapid transition to the yeast form with n-dodecane, a medium-chain aliphatic hydrocarbon. Thus, the fungus displayed a differential behavior towards the two types of saturated hydrophobic substrates.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.2
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• pp.176-184
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• 1998

A total of 125 pigs (5.8 kg of BW) were allotted in a completely randomized block design. Treatments were coconut oil, corn oil, soybean oil, tallow and tallow+lecithin. Each treatment had 5 replicates with 5 pigs per replicate. From d 0 to 7, pigs fed vegetable oil supported greater average daily gain (ADG) and improved feed/gain (F/G) compared to pigs fed the animal fat. Addition of lecithin to tallow increased ADG by 7.2%. Feed intake were similar for all treatment groups. From d 8 to 14, pigs fed coconut oil and soy oil showed better ADG and average daily feed intake (ADFI) than any of the others. From d 15 to 21, pigs fed the tallow diets had lower gains (p < 0.05) than those fed diets that contained vegetable oil and tallow with added lecithin. The effect of different fat sources on gain became smaller with age. Feed intakes were similar between the vegetable oil and lecithin supplemented diets each week postweaning except for pigs fed tallow (p < 0.05). Feed : gain ratios were superior during the initial 2 weeks postweaning period when pigs were provided vegetable oil diet compared with pigs fed tallow. All pig groups had similar feed : gain ratios during 3 weeks. Combinations of tallow with lecithin tended to have intermediate feed/gain ratio. It was found that vegetable oils were much better in improving growth rate of the piglets. Lecithin significantly improved growth rate and feed efficiency of the pigs through the whole experimental period compared to tallow. Coconut oil was the most effective in improving growth of pigs during the first two weeks postweaning. Corn oil had equal value with soy oil in improving growth performance of weaned pigs. When vegetable oil was added, the digestibilities of nutrients except for minerals were higher than when the tallow was fed. Nutrients digestibility was similar among vegetable oils. The addition of lecithin to tallow increased digestibility of gross energy, dry matter, ether extract and crude protein. Crude ash and phosphorus digestibility were not affected by the treatments. Dry matter excretion was not different among treatments except for tallow which showed significantly higher dry matter excretion (p < 0.05), while nitrogen excretion was significantly decreased in pigs fed vegetable oil sources. However, Phosphorus excretion was not affected by the different fat sources.

• Korean Journal of Food Science and Technology
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• v.8 no.4
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• pp.242-246
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• 1976

These experiment were conducted to investigate the characteristics of the purified lipase of Rhizopus japonicus. 1. The optimum pH for the lipase action was 6.8, the stable pH ranged $5.0{\sim}8.0$ and the optimum temperature was $35^{\circ}C$. The Purified lipase was stable below $45^{\circ}C$ and inactivated abruptly above $45^{\circ}C$ 2. Coconutoil castor oil and palm oil were most favorably hydrolyzed by the purified lipase, wheres olive oil and soybean oil were slightly less than the former three, and Tween 80 was hydrolyzed only 30% compared with coconut oil. 3. The purified lipase was activated by $Ca^{++}$ and $Mg^{++}$, whereas it was inhibited by $Hg^{++}$ and $Fe^{++}$.

• Korean Journal of Agricultural Science
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• v.37 no.1
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• pp.69-72
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• 2010

This study explored the solid fat index (SFI) of structured lipids (SLs) synthesized by lipase-catalyzed (Lipozyme TLIM) interesterification using hydrogenated coconut oil (HCO), palm oil (PO) and palm stearin solid (PSS). SLs were produced using three blends of HCO/PO (60:40, w/w), HCO/PSS (40:60 and 60:40, w/w), and HCO/PO/PSS (32:48:18, w/w/w) to find a desirable confectionary fat by monitoring melting and crystallization behaviors of SFI of SLs using differential scanning calorimetry (DSC). SFI of HCO/PSS (60:40) and HCO/PO/PSS (32:48:18) at $25^{\circ}C$ were 70% and 68%, respectively. These results suggest that HCO/PSS (60:40) and HCO/PO/PSS (32:48:18) may be useful as potential SLs of a confectionary fat.