• Journal of Nutrition and Health
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• v.24 no.5
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• pp.408-419
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• 1991

The effects of various dietary fats on plasma lipids. liver lipids, and Plasma Peroxide levels were studied in rats fed for 6 wk with diets containing 15 wt% fat, as sesame oil. raw perilla seed oil. roasted perilla seed oil, heated perilla seed oil. mackerel oil or beef tallow. TBA values of these lipids during 4 wk storage, and linolenic acid contents of three kinds of perilla seed oil were also measured. Linolenic acid contents of raw perilla seed oil. roasted perilla seed oil and heated perilla seed oil were 62.3%, 61.6% and 53.1% respectively. Raw perilla seed oil showed the lowest rate of lipid peroxidation after 4 wk storage at 4$^{\circ}C$, and mackerel oil showed the highest peroxidation rate. The plasma cholesterol levels of rats consuming diets in which the carbohydrate was rice were not affected by n-3 PUFA. Rather, the degree of peroxidation seems to have a direct effect on cholesterol levels as shown by the hypocholesterolemic effect of raw perilla seed oil and beer tallow. However. the HDL-cholesterol level was greater in rats fed either roasted perilla seed oil or mackerel oil. Rats fed roasted perilla seed oil and raw perilla seed oil had lower levels of plasma triglycerides than rats fed beef tallow. In rats fed roasted perilla seed oil, the total lipid and cholesterol contents of liver were significantly lower than in those fed the other kinds of perilla seed oil. The plasma lipid peroxide levels were lower in rats fed either roasted perilla seed oil or beef tallow.

• The Korean Journal of Food And Nutrition
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• v.9 no.4
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• pp.504-508
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• 1996

This study was performed to investigate the browning intensity and electron donating ability of browning material in perilla oils from seeds roasted at 150~21$0^{\circ}C$ for 10~30 min. It was also investigated the oxidative stability of the blended perilla oil on the basis of sensory property and oxidative stability. The browning intensity in perilla oil increased with the roasting temperature and time increased. The browning intensity of perilla oil from seed roasted at 21$0^{\circ}C$ for 30 min indicated 13 times higher than that of perilla oil from seed at 15$0^{\circ}C$ for 10 min. Electron donating ability on DPPH of browning materials presented in perilla oils increased with the roasting temperature and time increased. The electron donating ability of browning materials in perilla oil from seed reasted at 21$0^{\circ}C$ for 30 min indicated 3 times higher than those of perilla oil from seed at 15$0^{\circ}C$ for 10 min. In conclusion, for the improvement of oxidative stability of perilla oil, perilla seed should be roasted at 21$0^{\circ}C$ for 30 min. These results suggest that browning materials formed between sugars and amino acids attribute to improve quality of oil such as sensory properties and oxidative stabilities. For the improvement of sensory property and oxidative stability of oil, perilla oil from seed roasted at 19$0^{\circ}C$ for 20 min was blended with the oil from seed roasted at 21$0^{\circ}C$ for 30 min as ratio of 85 : 15.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.374-378
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• 1996

The oxidative stabilities of perilla oil increased as roasting temperature and time increased. Induction period of the perilla oil from unroasted perilla seed was 3.9 days, but that of the oil from perilla seed roasted at $210^{\circ}C$ for 30 min was 55 days. The electron donating ability(EDA) on DPPH by perilla oils increased as the roasting temperature and time increased. EDA of the unroasted perilla oil was 24% but that of the perilla oil roasted at $210^{\circ}C$ for 30 min was 64%. These results indicated that the reducing compounds were formed during the roasting process. The fluorescence intensity in perilla oil increased as the roasting temperature and time were increased. This result indicated that Maillard reaction has occurred during the roasting process and the reaction products seemed to provide stability to perilla oil.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.8-13
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• 2012

Effects of UV irradiation on lipid oxidation in perilla seeds and perilla oil were evaluated by determining the contents of peroxides, conjugated dienoic acids, and thiobarbituric acid reactive substances, and analyzing fatty acid composition. Tocopherols and polyphenol contents were also determined. Perilla seeds were unroasted or roasted at $180^{\circ}C$ for 20 min, and perilla oil was obtained by pressing the roasted perilla seeds. Lipid oxidation during UV irradiation was higher and faster in perilla oil than that in perilla seeds, with a slight loss of linolenic acid. Unroasted perilla seeds were more oxidation-stable than roasted seeds. Tocopherols and polyphenols were degraded during UV irradiation, with a higher degradation rate observed in unroasted perilla seeds than in roasted ones. Antioxidant concentration dependency of the lipid oxidation during UV irradiation was higher in perilla oil than that in perilla seeds, and the contribution of polyphenols to oxidative stability was higher than that of tocopherols in all samples.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.28-32
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• 1993

In order to elucidate the temperature and pressure effect on the oil expression of perilla seed, recovery of expressed oil (REO) and volumetric strain of both roasted and unroasted perilla seeds were observed at different temperature, pressure and for different periods of press. In this experiment, moisture content of perilla seed was adjusted to 2.5% and temperature used were 30, 40, 50 and $60^{\circ}C$. Pressure applied were 10, 30, 50 and 70 MPa, and periods of press were 5, 7, 9 and 11 min. As temperature and pressure were increased or periods of press was lengthened, REO and volumetric strain of pressed cake were increased. Maximum REO of unroasted perilla seeds were found to be 85.59% and those of roasted perilla seeds be 85.30%, at 70 MPa, $60^{\circ}C$, and for 11 min. Viscosity of expressed oil were exponentially dependent on temperature and REO were increased as viscosity was decreased. From statistical analysis between effects of expression factors and REO and volumetric strain of pressed cake, importance of their effects was decreased in the order of pressure, temperature, $temperature{\times}pressure$ and periods of press. The multiple regression equation between REO(Y) and temperature (T), pressure (P), and periods of press (D) were as follows; $Y=7.95+36.85P+1.12T^2-0.55TP-5.08P^2\;r^2=0.97$ for unroasted perilla seed (p<0.01), $Y=4.50T+39.23P+0.83T^2-1.71P-5.07P^2\;r^2=0.99$ for roasted perilla seed (p<0.01).

• The Korean Journal of Food And Nutrition
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• v.17 no.2
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• pp.220-228
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• 2004

Dynamic headspace purge conditions were investigated to obtain minimum loss of high volatile compounds by breakthrough and maximum recovery of low volatile components of roasted perilla seed oil (RPSO). A response surface methodology was applied to evaluate the effect of purge temperature, purge time, and sample weight on $\ell$ n (total peak area), breakthrough ratio, and peak area of perilla ketone the least volatile component of RPSO. Sample weight was the most important factor on the $\ell$ n (total peak area) but it did not affect peak area of perilla ketone. All process variables significantly influenced breakthrough ratio. The optimum condition was determined by superimposing contour plots at purge temperature of 48$^{\circ}C$ for 12 min purge time at sample weight of 0.60 g. 2-Propanone, 2-butanone, acetic acid, 2-methyl propanal were main breakthrough compounds in RPSO flavor.

• Applied Biological Chemistry
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• v.37 no.1
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• pp.14-18
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• 1994

In order to elucidate the interaction effect between temperature and moisture content on the oil expression of perilla seed, recovery of expressed oil (REO) and volumetric strain of pressed cake (VSPC) of both roasted and unroasted perilla seeds were observed at different temperatures of 30, 40, 50 and $60^{\circ}C$, and different moisture contents of 2.5, 4.5, 6.5 and 8.5% (w.b). And duration of press was 11 min and applied pressure was 50 MPa. At the low temperature REO and VSPC of roasted and unroasted perilla seed increased in high moisture content and at the high temperature those increased in low moisture content. But REO and VSPC at 8.5% moisture content were decreased without relation to temperature. From the analysis of variance between expression factors and REO and VSPC, temperature and moisture contents showed high significance. Also the interaction effect between temperature and moisture content was higher than temperature. In our experimental conditions, the highest interaction effect between expression factors was observed in the range of $2.5{\sim}4.5%$ of moisture content in all temperatures. The maximum REO of unroasted perilla seeds was observed as 84.4% at 2.5% of moisture content and $60^{\circ}C$, and that of roasted one was as 84.3% at 6.5% of moisture content and $30^{\circ}C$.

• Applied Biological Chemistry
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• v.39 no.2
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• pp.118-122
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• 1996

The main objectives of this study was to characterize physicochemical properties, oxidative stability and sensory property of perilla oil obtained by various roasting temperature and time. Roasting temperature of perilla seed was conducted from $150^{\circ}C\;to\;210^{\circ}C$ at the increment of $20^{\circ}C$, and roasting time was 10, 20 and 30 min. Yield of perilla oil was increased as the roasting temperature and time were increased. The content of linolenic acid, a major fatty acid in perilla oil, was 60%. There was no differences in fatty acid composition upon the roasting conditions. Unsaturated fatty acid was contained more than 88% of the total fatty acids. Contents of phosphorus in perilla oils were decreased as the roasting temperature and time were increased. Phosphorus contents were significantly decreased at $190^{\circ}C$ for 30 min and $210^{\circ}C\;for\;20{\sim}30$ min. Tocopherol contents were unchanged at the roasting conditions of present study and gamma-tocopherol was shown to be the major tocopherol. Sensory evaluation of perilla oil roasted in various conditions showed significant differences in taste, color, flavor and palatability. The perilla oil roasted at $190^{\circ}C$ for 20 min had the best palatability.

• Food Science and Preservation
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• v.15 no.4
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• pp.556-561
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• 2008

This study was carried out to identify the cause of benzo(a)pyrene[B(a)P] production during the manufacture of sesame oil and perilla oil, and to minimize such B(a)P synthesis. The distribution of B(a)P in sesame seed and perilla seed differed with seed-growing district, the range was $0.06{\sim}0.31{\mu}g/kg$ in domestic seed and $0.12{\sim}0.47{\mu}g/kg$ in imported seed. B(a)P contents after roasting at $220^{\circ}C$ for 20 min in sesame seed and perilla seed were $1.87{\sim}2.47{\mu}g/kg$ and $2.12{\sim}2.43{\mu}g/kg$, respectively, and levels in oils obtained from the roasted seeds were $3.68{\mu}g/kg$ and $4.64{\mu}g/kg$, respectively. These data refer to seeds subjected to codsed roasting. With open roasting, the levels were $0.63{\mu}g/kg$ and $0.56{\mu}g/kg$, respectively. Closed roasting resulted in absorption of B(a)P, with consequent high levels in oils. We introduced forced ventilation during closed roasting. We tested various methods to remove B(a)P from sesame oil and perilla oil. Neither centrifugation nor filtering with diatomite and diatomiteactive carbon removed B(a)P. A filtering method using active carbon was effective. But this method adversely affected the color and flavor of sesame oil and perilla oil.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1212-1219
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• 1999

The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.