• Transactions of the Korean Society of Automotive Engineers
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• v.15 no.6
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• pp.81-86
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• 2007

Biodiesel fuel that consists of saturated and unsaturated long-chain fatty acid alkyl esters is an alternative diesel fuel produced from vegetable oils or animal fats. However, air causes autoxidation of biodiesel fuel during storage, which can reduce fuel quality by adversely affecting its properties, such as the kinematic viscosity and acid value. One approach for improving the resistance of fatty derivatives to autoxidation is to mix them with antioxidants. This study investigated the effectiveness of five such antioxidants in mixtures with biodiesel fuels produced by three biodiesel manufacturers : tert-butylhydroquinone (TBHQ), butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), propyl gallate (PrG) and $\alpha$-tocopherol. Oxidation stability was determined using Rancimat equipment. The results show that TBHQ, BHA, and BHT were the most effective and $\alpha$-tocopherol was the least effective at increasing the oxidation stability of biodiesel. This study recommends that TBHQ and PrG be used for safeguarding biodiesel fuel from the effects of autoxidation during storage.

• Korean journal of food and cookery science
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• v.16 no.6
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• pp.629-639
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• 2000

The study was carried out to compare the antioxidant activities of products from caramel-type-browning reaction of xylose(XY), glucose(GL), sucrose(SU), glucose + citric acid (GLCA), glucose + sodium citrate(GLSC), glucose + glycine(GLGC) heated at 80, 120 or 140$^{\circ}C$ for 24 hr. 1. The hydrogen donating ability (HDA) of browning reaction products was generally enhanced as the browning temperature and time increased. The HDAs of the browning reaction products heated at 80$^{\circ}C$ for 24 hr were in the order of GLSC (0.387) > GLSC (0.362) > GLCA (0.301) > GL (0.299) > XY (0.290) > SU (0.281). But they were in the order of GLSC (0.543) > SU (0.328) > GL (0.309) > GLGC (0.325) > XY (0.298) > GLCA (0.275) under the condition of heating at 140$^{\circ}C$ for 24 hr. 2. The antioxidant activities of the anhydrous ethanol extracts of the browning mixtures were inferior to that of TBHQ as measured in com oil, but SU was superior to tocopherol in its antioxidant activity. All the browning mixtures showed antioxidant activities when heated at 80$^{\circ}C$; however, only SU and GLCA showed the activites at 120 or 140$^{\circ}C$. And the antioxidant activity of the SU extract was higher than that of TOCO. The antioxidant activities of the ethanol extracts were in the order of TBHQ > GLCA > GLGC > TOCO > SU > XY > GL > GLSC > control at 80$^{\circ}C$, TBHQ > SU > TOCO > GLCA > control > GLSC> XY > GL > GLGC at 120$^{\circ}C$, and TBHQ > SU > TOCO > GLCA > control > GLSC > GLGC > XY > GL at 140$^{\circ}C$.

• Journal of Life Science
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• v.21 no.8
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• pp.1094-1099
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• 2011

Antimicrobial efficacy of high pressure (HP) can be enhanced by the application of additional hurdles. The objective of this study was to assess the enhancement in pressure lethality by tert-butylhydroquinone (TBHQ) treatment, against bacterial spores that are considered significant in the food industry. Spores of Clostridium sporogenes, Bacillus cereus and B. subtilis were prepared. Spore suspensions containing TBHQ (200 ppm, dissolved in dimethyl sulfoxide, DMSO) were pressurized at 650 or 700 MPa at 54-72$^{\circ}C$ for 5 min. Inactivation of bacterial spores resulted only with HP treatment. The population of B. subtilis spores was more inactivated by HP than those of B. cereus and C. sporogenes spores. Inactivation of C. sporogenes spores using pressure was more affected by the germinated population, compared to Bacillus spores. The inactivation of Bacillus spores increased when pressurized at 70$^{\circ}C$, compared to 54$^{\circ}C$. On the other hand, the degree of germination-induced lethality for Bacillus spores decreased at 70$^{\circ}C$. When spores were treated with a combination of DMSO-HP and TBHQ-HP, these treatments seemed to protect the spores against HP, especially at 54$^{\circ}C$. Further mechanistic studies involved in inducing germination by HP and using a subsequent sporicidal agent will be needed for a better understanding of bacterial spore inactivation.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.444-448
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• 1993

Flavor compounds of pentane, hexane, hexanal and total volatiles formed during $65^{\circ}C$ storage of ramyon fried in palm oil with ${\alpha}-tocopherol$, RHA, TRHQ, rosemary extract or defatted ricebran extract were determined by static headspace gas chromatography. The levels of the antioxidants used in the frying oil were 100 or 200 ppm, and an additional level of 300 ppm was employed in the case of ${\alpha}-tocopherol$ ${\alpha}-Tocopherol$ decelerated the formation of all the flavor compounds when used at 100 or 200 ppm, and the former was more effective than the latter. However, 300 ppm of ${\alpha}-tocopherol$ accelerated the flavor compound formation in ramyon during storage. One hundred ppm of BHA and TBHQ contributed to the reduction in flavor compound formation in the stored ramyon, whereas 200ppm level accelerated the compound formation. Rosemary extract and defatted ricebran extract lowered the flavor compound formation in ramyon when used at 100 or 200 ppm in palm oil. Their lowering effects were similar to that of ${\alpha}-tocopherol$, and superior to that of TBHQ. suggesting a possible utilization of defatted ricebran extract as a new natural antioxidant.

• Korean Journal of Food Science and Technology
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• v.21 no.3
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• pp.409-418
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• 1989

The oxidative stability of the ramyon prepared with ricebran oil fortified with ${\alpha}-tocopherol$, BHA, TBHQ, and ascorbyl palmitate+citric acid or blended with palm oil was studied to assess the suitability of the oil as the frying oil. The antioxidants were added to a ricebran oil at 0.02% level, respectively, while blended oils were prepared by adding a palm oil to the ricebran oil at ratios of 3:7, 5:5, and 7:3. Ramyon samples were prepared by frying steamed noodel with the oils. They were stored in dark at $35.0{\pm}0^{\circ}C$. for 90 days. Peroxide, acid, iodine values, dielectric constant, and fatty acid composition of the oils extracted from the samples were determined regularly. The oxidative stability of the extracted oils and storage stability of the samples were estimated from the results of the determinations. ${\alpha}-tocopherol$ did not exert any appreciable antioxidant effect on the extracted oil while BHA demonstrated some effect. Ascorbyl palmitate with citric acid and especially TBHQ exerted a considerable effect. The storage stability of the samples fried with the oil fortified with TBHQ was as good as that of the samples prepared with the palm oil. The stability of the samples improved as the palm oil content In the frying oil increased. The stability of the samples fried with the blended oil containing 70f) palm oil was comparable to that of the samples prepared with the pure palm oil

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.411-414
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• 1990

Antithiamin activities of BHA, BHT PG and TBHQ of synthetic phenolic antioxidants at various pH's and temperatures were studied. All antioxidants had little antithiamin activity as is the case with control group at pH 4 and $38^{\circ}C$, but antithiamin activity was stronger at $60^{\circ}C$ than at $38^{\circ}C$ under the same pH. Meanwhile, the destruction of thiamin incubated at $38^{\circ}C$ was more rapid at pH 7 than at pH 4, and the destruction of thiamin at pH 7 was much more rapid at $60^{\circ}C$ than at $38^{\circ}C$. BHA and BHT had little, or extremely slight antithiamin activity. Antithiamin activity of PG was comparatively strong, but TBHQ had the strongest antithiamin activity among synthetic phenolic antioxidants examined.

• Korean Journal of Food Science and Technology
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• v.22 no.7
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• pp.846-851
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• 1990

An attempt was made in this study to investigate the possibility of processing garlic into an garlic oleoresin and investigate on the storage stability of it. To obtain a garlic oleoresin, water, phosphoric acid, garlic extract, poly sorbate and KM-72 as antiform agent were mixed with lecithin, and then these mixtures were homogenized at $50{\sim}55^{\circ}C$ for $5{\sim}7\;min$, cooled down to $25^{\circ}C$, and finally mixed with TBHQ (tert-butylhydroquinone) as antioxidant and garlic essential oil. Optimum components for garlic oleoresin consisted of 1.0% garlic essential oil, 10.5% garlic extract, 10.0% poly sorbate, 0.01% KM-72, 18.0% lecithin, 0.05% TBHQ, 0.15% of phosphoric acid solution and 60.0% water. Judging from thiosulfinate and pyruvate content, and sensory evaluation, quality damage of garlic oleoresin hardly occurred at $5^{\circ}C$ but occurred considerable level at $25^{\circ}C$ during storage for 60 days.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.58-70
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• 2002

In an attempt to compare the antioxidation effects of constrain the oxidation and improve the structural stability, retinol and various antioxidants were together encapsulated by liposome. Four water soluble and four oil soluble antioxidants were tested for performance. The influence of tertiary butylhydroquinone(TBHQ), ${\alpha}$-glycosyl rutin(${\alpha}$-G rutin), licorece, pycnogenol as water soluble antioxidants and butylated hydroxytoluene(BHT), ${\alpha}$-lipoic acid, ferulic acid, natural concentrated tooopherol(no-tocopherol) as oil soluble antioxidants on the constraint of oxidation of retinol were investigated. Additional study was conducted to compare the synergic effect of antioxidation for retinol with licorice, pycnogenol, ${\alpha}$-lipoic acid and BHT. All the antioxidant used at the study constrained oxidation of retinol. The effect of antioxidation for retinol increased in order of licorice, pycnogenol, TBHQ, ${\alpha}$-G rutin as water soluble antioxidants and ${\alpha}$-lipoic acid, BHT, no-tocopherol, ferulic acid as oil soluble antioxidants. In conclusion, ${\alpha}$-lipoic acid is more effective retinol antioxidants than BHT. And the combination of ${\alpha}$-lipoic acid and BHT gave best synergic among six combinations.

• Journal of Food Hygiene and Safety
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• v.12 no.4
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• pp.310-314
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• 1997

Antithiamin activities of BHA, BHT, PG and TBHQ of synthetic antioxidants on the effect of temperature and pH was determined by means of HPLC. The influence of synthetic antioxidants on the degration of thiamin was found to be dependent on temperature and pH. The degradation of thiamin was considerably more rapid at pH 7 than pH 4. The influence on the heat of synthetic antioxidants at pH 4 and 38* was extremely slight, but the degradation of thiamin at pH 7 was much more rapid at 60* than at 38*. After 24 hours of incubation both PG and TBHQ at pH 7 and 60* nearly completely destroyed thiamin. Tests of antithiamin activities showed that TBHQ, which was decomposed completely in 72 hours, was more effective than PG at pH 7 and 38* but BHA and BHT hardly had antithiamin activities which was evaluated under various reactions of pH and temperature. Thiamin degradation, at pH 7 and 6$0^{\circ}C$, was proportional to the concentration of PG. When the ratio of PG to thiamin was increased from 0.15:1 to 2:1, the degradation rate also increased. However, the change between ratio of 1:1 and 2:1 was negligible.

• Korean journal of food and cookery science
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• v.15 no.1
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• pp.55-60
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• 1999

Free phenolic acid, soluble phenolic acid ester and insoluble bound phenolic acid were extracted from defatted perilla flour. Their antioxidative effects were compared with those of BHA, AE and TBHQ for soybean oils by measuring acid and peroxide values at 60$^{\circ}C$ for 25 days. The patterns of these extracts were compared by using gas chromatography. Free phenolic acid and soluble phenolic acid ester extracts showed a higher antioxidative effects than BHA and AP. Among phenolic extracts, free phenolic acid showed the most effective antioxidant activity in soybean oil. Six types of free phenolic acid, 3 types of soluble phenolic acid ester, and 2 types of insoluble phenolic acid were found in the extract.