• Korean journal of food and cookery science
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• v.29 no.6
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• pp.805-814
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• 2013

Lotus root, dried laver, and perilla leaf bugak, Korean traditional fried cuisine, were prepared with fermented glutinous rice batter and unroasted sesame oil or wheat flour batter and soybean oil and their physicochemical characteristics was evaluated. Bugak with fermented glutinous rice batter and unroasted sesame oil showed higher hardness, possibly brittleness than bugak with wheat flour batter and soybean oil. Oil absorption was higher in bugak with fermented glutinous rice batter and unroasted sesame oil than bugak with wheat flour batter and soybean oil, however, the lipid oxidation, evaluated by conjugated dienoic acid and p-anisidine values, was significantly lower in bugak with fermented glutinous rice batter and unroasted sesame oil. Frying oil strongly influenced the degree of lipid oxidation and fatty acid composition of bugak lipid. Different preparation of bugak did not show great effects on the contents of chlorophylls and carotenoids of dried laver and perilla leaf bugak, possibly due to protection by rice or wheat flour batter coating.

• Analytical Science and Technology
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• v.15 no.3
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• pp.248-255
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• 2002

The contents of ${\alpha}$-, ${\beta}$-, ${\gamma}$-, and $\delta$-tocopherols in sesame oils were determined by high performance liquid chromatography with UV detection. ${\alpha}$-Tocopherol contents ranged from 10.28 to 19.79 mg/g oil, ${\beta}$-tocopherol contents from 8.22 to 20.10 mg/g. However, both ${\gamma}$- and $\delta$-tocopherol were less than 1.49 mg/g or not detected. ${\gamma}$-Tocopherol was not detected from both unroasted white and black sesame seed oils. Significantly higher level of tocopherol in sesame oil than other oils is an evidence of the reason why it is highly stable and prevents oxidation. The tocopherol composition for twenty sesame oils was classified by using principal component analysis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.5
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• pp.785-789
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• 1995

In order to optimize the batch expression of sesame oil, recovery of expressed oil(REO) from roasted and unroasted sesame seeds were observed at different temperature, pressure, pressing duration and moisture content, and relatinship between REO and effects of expression factors were analysed. REO was high at 2.5~4.5% moisture content, 30~$50^{\circ}C$ and 30~50MPa, and decreased abruptly with increasing moisture content above 4.5%. The optimum temperature, pressure, pressing duration and moisture content were $40.1^{\circ}C$, 54.4MPa, 21.7min and 1.3% for unroasted seeds and $44.4^{\circ}C$, 37.8MPa, 14.4min and 2.52% for roasted seeds, respectively. REO in optimum condition was 84.6% in unroasted seed and 81.7% in roasted seed. From the statistic analysis between effects of expression factors and REO, importance of their effects was decreased in the order of moisture content, pressure, temperature and pressing duration. And also interaction effects were high in $pressure{\times}moisture$ content, $temperature{\times}moisture$ content and temperature pressure. The multiple regression equation between REO(Y) and temperature(T), pressure(P), moisture content(M), and pressing duration(D) were as follows ; $Y=18.20$ $35.66P$＋$24.52M-4.45P^{2}-1.20TM-4.02PM-6.62M^{2},\;r^{2}=0.89$, for unrosated sesame seed, $Y=117.93$＋$16.40P-58.61M-2.75P^{2}$＋$1.79TM-1.65PM$＋$7.16M^{2},\;r^{2}$$=0.91$ for roasted sesame seed.

• Applied Biological Chemistry
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• v.38 no.5
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• pp.425-430
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• 1995

The effects of oxidation stability and flavor acceptability of soybean oil by roasting and refining treatment were investigated in this study. The peroxide values of crude oil from unroasted soybean(COUS) were more increased than those of crude oil from unroasted soybean(CORS) during storage under fluorescence light at $45^{\circ}C$. Induction time by the Rancimat Method was 44.9 and above 88.7 hours on COUS and CORS respectively. The order of oxidation stability of oil was crude>degummed>alkali-refining>deodorized>bleached oil in terms of peroxide value, while that of oxidation stability of oil was crude>degummed>deodorized>alkali-refining>bleached oil in regard to induction time by the Rancimat Method. The correlation coefficients between induction time and two charateristics(absorbance of browning reaction products and phosphorous contents) were highly significant, while that between induction time and tocopherol contents was not high during refining stages. The scores for the sensory evaluation of flavor on sesame oil and CORS was 9.269 and 8.269 respectively, but it was not significant between two oils.

• Korean Journal of Food Science and Technology
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• v.32 no.2
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• pp.246-251
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• 2000

This study was investigated to compare the changes of antioxidative compounds in sesame oil with roasting temperature$(110^{\circ}C{\sim}230^{\circ}C)$. Lightness was decreased markedly over $170^{\circ}C$. In the changes of lignan contents, 7 different lignans unchanged up to $170^{\circ}C$ and sesamolin and sesamin decreased markedly, whereas sesamol, unknown1, unknown3 increased drastically at the higher temperatures. In tocopherol contents, ${\gamma}-tocopherol$ decreased from 70.59 mg% in unroasted oil to 33.87 mg% at $220^{\circ}C$, and to 26.73 mg% at $230^{\circ}C$. In the result of AOM(active oxygen method) test carried out at $120^{\circ}C$ for evaluating oxidative stability, the induction period of unroasted oil was 4.12 hrs and that of roasted oils was increased with roasting temperature (induction period at $220^{\circ}C$ was 27.9 hrs.). From the above results, it was confirmed that correlation coefficient between oxidative stability and lightness is -0.993 and that between oxidative stability and sesamol content is 0.934 above $170^{\circ}C$. Therefore its remarkable oxidative stability with the roasting temperature, might be considered to be due to the increase of sesamol, other lignans(unknown 1, unknown 3).

• Korean journal of food and cookery science
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• v.30 no.6
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• pp.767-773
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• 2014

In vitro antioxidative activities and antioxidants of the lotus root, dried laver, and perilla leaf bugak, Korean traditional fried cuisine, were evaluated. The bugak was prepared with fermented glutinous rice batter and unroasted sesame oil for use in the pan-frying. The perilla leaf bugak showed the highest radical scavenging activity and reducing power, with the lowest in the lotus root bugak. The antioxidative activity of the blanched lotus root was lower than the dried laver or the perilla leaf. Polyphenol content was higher in the perilla leaf bugak than the lotus root or the dried laver bugak, and tocopherols were mainly derived from frying oil. The antioxidative activity of bugak was correlated well with polyphenol contents, but there was no correlation between tocopherol contents and the antioxidative activity.