• Journal of the Korean Applied Science and Technology
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• v.7 no.1
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• pp.63-70
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• 1990

Influence of mixing ratio of blending oil (rice bran oil : RBD palm olein = 1 : 1, 1 : 4 mixture: w/w) and natural tocopherol, citric acid, and sodium polyphosphate on enhancement of oxidation stability of blending oil under the condition of tap water infulx(1 ml/min/200g oil) were compared by AOM test after heating these system at l80$^{\circ}C$. In addition, the effects of tocopherol, and synergist on oxidition stability were also tested with potato chips fried with blending oil(1 : 4 mixture). The result obtained were as followes; 1. The test of RBD palm olein addition of 50% and 80% against rice bran oil on oxidation stability showed that the higher the palm olein contents in blending oil, the higher the oxidation stability. 2. The test of oxidation stability, adding l00ppm, 200ppm and 400ppm of natural tocopherol in two different types of blending oils, A(1 : 1 mixture) and B(1 : 4 mixture), disclosed that blending oil B was more positively effective, and this trend was superior at 200ppm level particularly, Furthermore, oxidation stability was enhanced remarkably upon addition of 100ppm of natural tocopherol, and 50ppm of citric acid together with 50ppm, 100ppm and 200ppm of sodium polyphosphate in general. Especially, 200ppm of sodium polyphosphate addition induced the most synergetic effect on oxidation stability showing as much as 3 times compare to control. 3. The results of oxidation stability obtained by peroxide value on potato chips fried with blending oil (1:4 mixture} added tocopherol, citric acid and sodium polyphosphate and preserved at $60^{\circ}C$ revealed that addition of tocopherol and 50ppm of citric acid together with 200ppm of sodium polyphosphate treatment was the most synergistic coinciding with AOM test results.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1513-1517
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• 2016

Rice bran contains high amounts of fiber and various phytochemicals, including vitamin E, ${\gamma}$-oryzanol, and phenolic acids. The oxidative stabilities of corn oil added with three rice bran extracts from two rice cultivars (Dasan 1 and Ilpum) were evaluated. The three rice bran extracts were unsaponifiable matter of rice bran (USM), methanolic extract of rice bran oil (MEO), and methanolic extract of defatted rice bran (MEDR). Each sample was stored at $50^{\circ}C$ for 24 days. Oxidation of these samples was determined every 3 days by measuring the peroxide value (POV) and conjugated diene value (CDV). Vitamin E content was analyzed on day 0 and day 24. The results show that the POV and CDV values of samples increased gradually during the storage period. The order of oxidative stability was shown as BHT> MEDR> MEO> USM> control, regardless of cultivars. In the case of vitamin E, ${\alpha}$-T, ${\gamma}$-T, ${\alpha}$-T3, and ${\gamma}$-T3 contents decreased by 89%, 31%, 83%, and 32% after storage for 24 days, respectively. In conclusion, MEDR showed higher oxidative stability and may have potential as a source of natural antioxidants in the oil industry.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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• pp.271-278
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• 2006

As for red pepper seasoning oil (RPSO), seasoning oil (SO) and pine needle oil (PNO), various organic solvent extracts from rosemary powder and tocopherol are treated as control group. At this time, amounts that are treated were all 1,000 ppm. It was observed by AV (acid value), POV (peroxide value) and carbonyl compounds content of the stored samples during 3 months at 60${\pm}$2$^{\circ}C$ incubation. Tocopherol was shown to be pro-oxidant than the antioxidant in all seasoning oil samples. Icreasing effect of storage stability of chloroform/MeOH extract was the most superior one. Final result of icreasing effect of storage stability from the determinated data was as follows. The storage stability of solvent system by AV and POV analysis was in the increasing order of chloroform/MeOH extract> ethyl alcohol extract>hot water extract>ethyl acetate extract>acetone extract>none treating group> tocopherol treating group, POV was chloroform/MeOH extract>ethyl alcohol extract ${\geq}$ ethyl acetate extract> acetone extract ${\geq}$ hot water extract>none treating group>tocopherol treating group and by carbonyl compound content analysis was in the increasing order of chloroform/MeOH extract>ethyl acetate extract>ethyl alcohol extract>hot water extract>acetone extract>none treating group>tocopherol treating group.

• The Korean Journal of Food And Nutrition
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• v.22 no.4
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• pp.508-516
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• 2009

Chiffon cakes with 2, 4, 6, 8, or 10% of mulberry powder were made. Specific gravity and batter stability of chiffon cake batter were measured. And moisture content, color, height, weight, texture of chiffon cakes were measured. Consumers also evaluated the chiffon cakes for their liking. Specific gravity of control batter was 0.5 and there were no significant differences between control and chiffon cakes with 2, 4, 6, and 8% of the mulberry powder. The sample with 10% mulberry powder had specific gravity of 0.64 and it was significantly higher compared to the control. Stability of the batters were measured using Turbiscan and the control was the least stable whereas the batter with 2% mulberry powder was the most stable. The moisture content and weight of the cake did not differ between the control chiffon cake and cakes with mulberry powder. The height of the cake was the highest for the control cake at 7.56cm, but the differences between control, and samples with 2, 4, 6, and 8% mulberry powder were not significant. The sample with 10% mulberry powder had lower height of 6.55cm. 'L', 'a', and 'b' values of crust decreased significantly with increased content of mulberry powder. Crumb color('L' and 'b' values) decreased as mulberry powder content increased, while the 'a' value increased. Hardness significantly decreased as mulberry content increased. However, fracturability and springiness did not differ between control and sample cakes. Resilience of the control and sample cakes prepared with 2% mulberry powder were lowest, and resilience increased significantly as the amount of mulberry powder increased beyond 4%. Control cake was preferred overall by consumers, while the color, softness, and flavor of mulberry powder prepared cakes(particularly 2% powder) were specifically preferred. Mulberry flavor and astringency increased as the amount of mulberry powder increased, while sweetness did not change. The intensity of the egg flavor significantly decreased as the amount of mulberry powder increased. Intensity ratings of off-flavor did not differ among control and sample cakes. We recommend the addition of 2~6% mulberry powder to the recipe for chiffon cake.

• Korean Journal of Food Science and Technology
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• v.49 no.1
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• pp.110-116
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• 2017

${\gamma}-Oryzanol-loaded$ calcium-pectin micro- and nanocapsules were prepared by ionic gelation to improve oxidation stability and the effect of particle size on capsule properties was investigated. The physical properties were influenced by preparation conditions such as concentrations of pectin, $CaCl_2$, ${\gamma}-oryzanol$, and hardening time. Particle sizes of micro- and nanocapsules that showed the maximum encapsulation efficiency and sustained release were $2.27{\pm}0.02mm$ and $347.7{\pm}58.1nm$, respectively. Microcapsules showed higher encapsulation efficiency ($50.73{\pm}1.98%$) than nanocapsules ($17.70{\pm}2.04%$), while nanocapsules showed more sustained release and higher stability than microcapsules. Release of ${\gamma}-oryzanol$ from both microand nanocapsules, which was low in gastric environments and promoted in intestinal environments, showed suitable characteristics for oral administration. Furthermore, antioxidant activity of ${\gamma}-oryzanol$ against autoxidation of linoleic acid was prolonged by both micro- and nanoencapsulation in a ferric thiocyanate test. Therefore, micro- and nanoencapsulation using pectin can be effective for improving biodelivery, stability, and antioxidant activity of ${\gamma}-oryzanol$.

• Journal of the Korean Society of Food Culture
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• v.18 no.2
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• pp.89-95
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• 2003

In order to evaluate the oxidative stability and sensory evaluation for the pine needle extracted oils, we prepared the pine needle extracted oils by the autoclave method with soybean and/or olive oils. The lipid peroxidation was monitored by measuring the formation of 2-thiobarbituric acid reactive substances(TBARS). In addition, the secondary reaction products of lipid oxidation were measured by fluorescence spectroscopy. A weight changing was decreased in oils added pine needle during storage periods. The formation of TBARS was the lowest in olive pine needle oils after 14 days storage, whereas it was the highest in soybean oil. The levels of fluorescent products in extracted oils added pine needle were also decreased in organic layers. According to the sensory evaluation, the scores of fragrance, taste and overall preference in savored laver using an pine needle extracted oils were no significant differences. Overall results suggest that the pine needle extracted oils can be developed to functional oil resources.

• Korean Journal of Food Science and Technology
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• v.49 no.5
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• pp.480-485
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• 2017

This study was conducted to examine the antioxidant activity of 80% ethanol extract of celery seeds and to verify the effectiveness of extracts as a natural antioxidant to improve the stability of oil-in-water emulsions. The radical scavenging activity of 80% ethanol extract of celery seeds was significantly increased at 0.125, 0.25, and 0.5 mg/mL (p<0.05). Additionally, the total phenolic content and FRAP value were equal to $8.2{\pm}2.3mol$ tannic acid equivalent/g extract and $195.0{\pm}12.6mol$ ascorbic acid equivalent/g extract, respectively. The headspace oxygen content was significantly higher in the group treated with 80% ethanol extract of celery seeds than in the control group (p<0.05). The amounts of lipid hydroperoxide and conjugated diene were significantly reduced compared to the control group (p<0.05). The results showed that the extract of celery seeds had excellent antioxidant ability and it could be used as a natural antioxidant owing to the increased oxidative stability of the emulsified product.

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.461-468
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• 2016

In recent years, various naturally occurring defence peptides such as plectasin have attracted considerable research interest because they could serve as alternatives to antibiotics. However, the production of plectasin from natural microorganisms is still not commercially feasible because of its low expression levels and weak stability. A tandemly arrayed plectasin gene (1,002 bp) from Pseudoplectania nigrella was generated using the isoschizomer construction method, and was inserted into the pPICZαA vector and expressed in Pichia pastoris. The selected P. pastoris strain yielded 143 μg/ml recombinant plectasin (Ple) under the control of the methanol-inducible alcohol oxidase 1 (AOX1) promoter. Ple was estimated by SDS-PAGE to be 41 kDa. In vitro studies have shown that Ple efficiently inhibited the growth of several gram-positive bacteria such as Streptococcus suis and Staphylococcus aureus. S. suis is the most sensitive bacterial species to Ple, with a minimum inhibitory concentration (MIC) of 4 μg/ml. Importantly, Ple exhibited resistance to pepsin but it was quite sensitive to trypsin and maintained antimicrobial activity over a wide pH range (pH 2.0 to 10.0). P. pastoris offers an attractive system for the cost-effective production of Ple. The antimicrobial activity of Ple suggested that it could be a potential alternative to antibiotics against S. suis and S. aureus infections.

• 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.

• KSBB Journal
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• v.25 no.6
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• pp.513-519
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• 2010

Marine bacterium producing pigment was isolated from the solar saltern of Mijo-myeon, Namhae, Korea. Based on phenotypic characteristics and 16S rRNA sequence analysis, the strain was identified as Kocuria sp., which produced a yellow pigment. The pigment showed UV absorption maximum at 469nm. The bacterial strain grew well on Marine broth 2216 culture medium. Productivity of the pigment reached the maximum value after 44 hours at $30^{\circ}C$, 2% NaCl and pH 6.0. The pigment was produced best when supplied by 1% lactose as a carbon source and 1% beef extract as a nitrogen source. The result of the color stability study showed that pigment extracted from the strain by ethanol was stable at $-20-25^{\circ}C$ and also showed higher stability over 70% for 14 days in light conditions at $25^{\circ}C$. The pigment extract was also stable for all metal ions tested, except for $FeCl_2$.