• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.257-267
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• 2007

The possibility of rapid non-destructive qualitative and quantitative analysis of vegetable oils such as perilla, com, soybean and rapaseed oils in sesame oils was evaluated. A calibration equation calculated by MPLS(Modified Partial Least Squares) regression technique was developed and coefficients of determination for perilla oil, com oil, soybean oil and rapaseed oil contents were 0.9992, 0.9694, 0.9795 and 0.9790 respectively. According to the data obtained from validation study, $R^2$ of contents of perilla, com, soybean, rapaseed oils were 0.997, 0.848, 0.957 and 0.968, and SEP of content of them 0.747, 5.069, 3.063 and 3.000 by MPLS respectively. The results indicate that the NIRS procedure can potentially be used as a non-destructive analysis method for the rapid and simple measurement of sesame oil mixed with other vegetable oils. The detection limits of the NIRS for perilla oil, com oil, soybean oil and rapaseed oil were presumed as 2%, $15{\sim}20%,\;15{\sim}20%$ and 10%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.2
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• pp.234-241
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• 1995

Effect of microwave heating on the oxidative stability of the soybean oil, sesame oil, butter and margarine were investigated by mearsuring fatty acids amout and tocopherol losses. The index for chemical properteis, free fatty acid, peroxide value, anisidine value, carbonyl value, conjugated diene and triene levels were also mearsured in the oil samples for 5, 10, 15 and 20 min of heating in a microwave oven. No significant difference was observed on the fatty acids composition in the fats and oils before and after microwave heating. During microwave treatment, the oxidative degradation of the tocopherols in the samples became greater with increasing heating time. The amount of tocopherols in the soild fats, butter and margarine, dropped drastically after 5 min of heating and reduced to 95% of their original levels after 20min heating ${\gamma}$-tocopherol in butter showed the most unstable states and completely destroyed during microwave treatment for 20min. On the other hand, 80% of tocopherols in the liquid oils were still remained after 5min of heating except $\delta$-tocopherol in sesame oil.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.21-26
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• 2015

Seasoned laver Pyropia spp. is a traditional Korean seafood that has gained popularity worldwide because of its unique taste, texture, and health benefits. It is prepared by roasting a sheet of dried laver, to which vegetable oils have been applied, at an ultra-high temperature (UHT) of $300^{\circ}C$. Therefore, the oxidative stability of the oils is the most important factor in determining the shelf life of seasoned laver products. In this study, we investigated changes in the thermal oxidative stability of six major vegetable oils (sesame, perilla, sunflower, rice bran, canola, and olive) during the seasoned laver processing. The oxidation induction time of each oil from the seasoned laver products was decreased compared with the fresh oil. These results indicate that the UHT treatment ($300^{\circ}C$, 10 s) induced thermal oxidation of the oils. Among the six seasoned laver oils, the induction times of olive (OL, 8.02 h) and sesame (SE, 5.31 h) oils were significantly higher than the other oils. The acid values (AVs) of OL and SE oils from the seasoned laver were 0.49 and 0.79, respectively. On the other hand, perilla oil had the overall worst thermal oxidative properties (induction time: 0.35 h, AV: 2.82). Our results provide useful information about seasoned laver products for researchers or manufactures.

• Korean Journal of Food Science and Technology
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• v.30 no.2
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• pp.260-265
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• 1998

In this study, volatile flavor compounds in sesame oils were analyzed by using pure-and-trap method and a gas chromatography. 2-ethoxy-3-ethylpyrazine was used as an internal standard and retention index (Kovat's number) for the volatiles were determined through the use of a n-paraffin $(C_5-C_{25})$ standards. A total of 33 volatile compounds including 14 pyrazines, 7 thiazoles, 4 pyridines, 2 oxazoles and 6 others were identified in the sesame oils. By comparing the total yields of volatile flavor compounds, the pyrazines are the most abundant compounds all of the oil samples and considered as good contributor to characteristic flavor of sesame oil. The oil from the seeds roasted in the electric pan at $200^{\circ}C$ and $230^{\circ}C$ for 10 minutes generated 277.06 ppm, 264.81 ppm in pyrazine and 15.16 ppm, 13.19 ppm in thiazole, respectively. The sensory evaluation of oil samples was also investigated. The sesame oil obtained from the sesame seeds roasted at $200^{\circ}C$ for 10 minutes with electric pan showed good flavor scores and quality among the all of samples.

• Applied Biological Chemistry
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• v.36 no.4
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• pp.284-289
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• 1993

The effect of oil refining processes-degumming, alkali-refining, bleaching and deodorizing-on oil characteristics and oxidation stability of sesame oil were investigated. The colors(L, a, b) of samples were markedly changed and their peroxide and acid values were decreased, while the other characteristics of samples were not changed during refining stages. The L values of alkali-refined, bleached and deodorized sesame oils were largely decreased and their a values were increased due to browning reaction during the storage at $70^{\circ}C$. The colors of crude and degmmed sesame oils were very stable and their peroxide, free fatty acid and conjugated dienoic acid values were slowly increased. Volatile carbonyl compounds formed by oxidation were increased during the storage at $70^{\circ}C$. The results indicated that refining processes did not affect the sesame oil characteristics but decreased the oxidation stability of sesame oil.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.648-652
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• 2003

Precise and rapid method out for distinguishing blended sesame oils through the electronic nose analysis was developed. Sesame oil was blended with corn oil at the ratio of 95 : 5, 90: 10, and 80 : 20 (w/w), respectively. Samples were then analyzed by gas chromatography, SPME-GC/MS, and the electronic nose composed of 12 different metal oxide sensors. Sensitivities $(delta\;R_{gas}/R_{air})$ of sensors from electronic nose were analyzed by principal component analysis (PCA). Proportion of the first principal component was 98.76%.

• Journal of Nutrition and Health
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• v.10 no.2
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• pp.44-53
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• 1977

The Korean origin edible oil sterol part of the rape, sesame and perilla oil can be separated from the other constituents of the non-saponifiable fraction, by the thin layer chromatography on the preparative Plates. The composition of sterols have been determined by gas liquid chromatography and thin layer chromatographic anlysis. Two sterols, ${\beta}$-sitosterol and campesterol were present in all of the oils. And brassicasterol were found in rapeseed oil in addition to the two sterols that were common to all of the oils studied. It was noted that ${\beta}$-sitosterol was the major sterol in the Korean original edible oils. The results showed that contents of sterols were campesterol 24.31%, ${\beta}$-sitosterol 58.90% ana Brassicasterol 11.54%, and $\Delta^7$-sterol 5.25% by method of triangulation and campesterol 26.16%, ${\beta}$-sitosterol 57.50%, brassicasterol 11.70% and ${\Delta}^7$-sterol 4.64% by method of Planimetry of rape seed oil. By sesame seed oil sterol compositions were campesterol 20.35%, stigmasterol 9.15%, ${\beta}$-sitosterol 43.49%, ${\Delta}^7$-sterol 11.25% and others 15.76% by method of triangulation and campesterol 16.79%, stigmasterol 8.69%, ${\beta}$-sitosterol 44.58%, ${\Delta}^7$-sterol 14.28% and others 15.56% by method of planimetry. Campesterol 12.45%, stigmasteriol 5.40%, ${\beta}$-sitosterol 72.32% and ${\Delta}^7$-Sterol 9.83% by method of triangulation-and campesterol 13.00%, stigmasterol 3.76%, ${\beta}$-sitosterol 74.57% and ${\Delta}^7$ sterols 8.67% by method of planimetry of perilla oil. Contents of totalsterol in Korean edible oils were 0.82% by rape, 0.58% by sesame and 0.45% by perilla, respectively.

• Proceedings of the EASDL Conference
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• 2004.10a
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• pp.13-30
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• 2004

There are two groups of significant functional constituents in sesame seeds on the whole; one is the vegetable oils and another is the anti-oxidative compounds. However, although high amounts of major fatty acids are synthesized in sesame seeds, their composition is unfavorable because the contents of alpha- and gamma-linolenic acid, the essential fatty acids, are very low or do not produced in sesame seeds. So, to increase these fatty acids in sesame seeds, one strategy is to overexpress their genes, ${\omega}$-3 fatty acid desaturase for alpha-linolenic acid and delta-6 fatty acid desaturase for gamma-linolenid acid, in them. Another molecular target is to enhance alpha-tocopherol, vitamin E, because its content is very low in sesame seeds. The enzyme, gamma-tocopherol methyltransferase, catalyzes the conversion of gamma-tocophero to alpha-tocopherol. Overexpression of this enzyme in sesame seeds could be also a good molecular breeding target. Reduction of phytic acid is also another molecular target in sesame seeds because phosphorus pollution may be caused by its high content in sesame seeds. Accordingly, to do so, one of target enzymes could be myo-inositol 1-phosphate synthase which is a key regulatory enzyme in the pathway of phytic aicd biosyntheses. In this lecture, a molecular strategy for development of value-added sesame crop is described in association with some results of our experiments involved in the molecular characterizations of the genes mentioned above.

• Journal of Nutrition and Health
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• v.13 no.4
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• pp.177-186
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• 1980

Experiments were carried out in order to compare the sesamol contents in the methanol extracts and unsaponifiable matters from raw and baked seeds of Korean sesame and perilla by thinchrography. The oil and sesamol contents of sesame seeds were higher than those of perilla seeds. The contents of sesamol in raw and baked sesame seeds were 0.22 and 0.096% respectively in methanol extracts and 0.41 and 0.29% respectively in unsaponifiable matters. The sesame contents in raw and baked perilla seeds were 0.0022 and 0.0043% respectively in methanol extracts and not detected in unsaponifiable matters.

• Journal of Nutrition and Health
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• v.19 no.3
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• pp.190-198
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• 1986

The result of the analytical experimental by HPLC on amino acid which is contained in such samples as white-raw-sesame, white-roast -seasame, black -raw -sesame, black-roast-sesame, raw-perilla seed and roast-perilla seed is as follows ; In the six smaples, the amino acid contents in raw seeds were all higher than those in roasted seeds, and the contents of alutamic acid and lysine were more reduced in roasted seeds than in raw seeds. All the amino acid contents except threoninewere highest in raw perilla seed. The amino acids which the six samples contain to a higher degree were in order of glutamic acid (18 %-21%), threonine(16%-19%), glycine (8%-9%), leucine(77.5%), aspartic acid (7%-7.4%), while methinine (1-2%) was contained least in all six samples followed by Isoleucine(3%).