• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.4
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• pp.553-558
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• 2002

To utilize the small redlip croaker, four kinds of seasoned fillet were produced. The nutrient composition, peroxide value and coliforms count of the products were determined, and sensory characteristics were evaluated. The seasonings consisted of the formula for commercial dried file fish added with water (A, control), green tea extract (B), rosemary extract (C) and soypaste with red pepper (D). The crude protein and carbohydrate contents of the products were in the range of 39~45% and 23~3l%, respectively. The lipid content of product B was the lowest, while that of product D was the highest among the tested products. All products showed similar amino acid profiles with a high content of glutamic acid, aspartic acid, glycine and lysine. The saturates in fatty acid composition were similar (50~51%) among the products. However, the polyenes were higher (17%) in product C than products A, B and D (13%). The peroxide value of product C was the lowest among the products. There were not significant differences in taste and color among the products.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.427-434
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• 2010

This study was conducted to investigate the changes in haem pigments, peroxide value, TBARS, free fatty acid contents and fatty acid composition of five muscles from low fat pork cuts during storage at $4^{\circ}C$ for 14 d. The myoglobin contents (Oxy, Met and Total) did not change significantly (p>0.05) as storage time increased. In addition, the peroxide value did not change significantly (p>0.05), but the thiobarbituric acid reactive substances were significantly (p<0.05) upregulated during chilled storage. The total free fatty acid contents of the longissimus dorsi muscle were significantly (p<0.05) upregulated, but the saturated, unsaturated, mono-unsaturated and poly-unsaturated fatty acid composition of the muscles did not change significantly (p>0.05) during chilled storage.

• Food Science and Preservation
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• v.16 no.4
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• pp.554-561
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• 2009

We investigated the antioxidative effects of solvent extracts of doenjang fermented using Bacillus subtilis DJI (DJI doenjang) in vitro. The solvents used for extraction were ethanol, n-hexane, and water. The antioxidative activities of DJI doenjang solvent extracts were measured by estimation of peroxide value, the presence of linoleic acid level, and nitrite scavenging activity, the Rancimat test, and 1,1-diphenyl-2-picryl hydrazyl (DPPH) free-radical generation, in comparison with the commercial antioxidant butylated hydroxytoluene (BHT). The peroxide value of an ethanol extract was lower than those obtained using n-hexane and water extracts. Furthermore, the peroxide value of the ethanol extract was similar to that obtained after BHT treatment. The nitrite scavenging activity was 23.36% after addition of 600 ppm DJI doenjang ethanol extract, and the DPPH free-radical scavenging activity was 19.06% under same condition, which shows that DJI doenjang ethanol extract exhibited lower antioxidative capacities than did BHT. In the Rancimat test, the ethanol extract (11.20 min induction time), n-hexane extract (7.58 min induction time), and water extract (8.26 min induction time) after treatment with 600 ppm DJI doenjang extracts demonstrated longer induction periods than did BHT (6.94 min). These results indicate that DJI doenjang has potential anti-oxidative activity.

• Korean Journal of Pharmacognosy
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• v.54 no.2
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• pp.80-87
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• 2023

Rancidity changes were examined for 6 herbal medicines, namely Persicae Semen, Armeniacae Semen, Lini Semen, Trichosanthis Semen, Arecae Semen, Myristicae Semen known to have relatively high fat content. In order to reduce rancidity of herbal medicines, samples were stored at 3 different conditions of room, refrigerating and freezing temperatures, and the rancidity was measured for 10 months with every 2 month interval. Fat content was extracted by using ethyl ether, and acid values and peroxide values, which are generally accepted indicators of fat rancidity, were measured. When storing Persicae Semen, Lini Semen and Arecae Semen at room temperature, the acid values increased as the storage period increased, and it was higher than when stored in refrigeration or freezing. The measurement of peroxide value showed more significantly higher initial degree of rancidity when Persicae Semen, Trichosanthis Semen, Arecae Semen and Myristicae Semen were stored at room temperature. It was observed that storing herbal medicines in refrigeration or freezing inhibited their rancidity compared to storing them at room temperature. To investigate the quality changes according to rancidity, the analysis of aflatoxins and indicator components showed that aflatoxins B₁ and B₂ were detected in Armeniacae Semen, Arecae Semen and Myristicae Semen, and the amount of amygdalin was well maintained within the specification standard.

• Korean Journal of Food Science and Technology
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• v.4 no.4
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• pp.259-264
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• 1972

Oxidative changes of the Ramyon lipids were studied under three experimental storage conditions. Ramyon was 1) exposed to fluorescent light irradiation at $25^{\circ}C$, 2) incubated in the dark at $40^{\circ}C$ and 3) irradiated with ultra-violet light at $25^{\circ}C$. In the study, changes in acid value, peroxide value, carbonyl value, TBA number, fatty acid composition and iodine value were determined with the lipids extracted from the Ramyon samples in intervals for a period of 20 weeks. Acid value, peroxide value, and TBA number of the samples under fluorescent light irradiation and $40^{\circ}C$ incubation increased slightly during storage, while a sharp increase of those values were noticed with the samples of ultra-violet light irradiation. Especially, the TBA number of the Ramyon lipid under ultra-violet light irradiation markedly increased within 10 weeks and then decreased. With this change in TBA number, however, the bound form of malonaldehyde increased gradually. During the storage under $40^{\circ}C$ incubation, and ultra·violet irradiation for 10 weeks, the content of linoleic and linolenic acids decreased, while palmitic and stearic acids increased. However, only small changes were noticed in iodine value of the samples. On the other hand, oxidative rancid odor appeared at the end of 16 weeks storage under fluorescent light irradiation and $40^{\circ}C$ incubation, while it took only 4 weeks with the sample stored under ultra-violet irradiation.

• The Korean Journal of Mycology
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• v.16 no.3
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• pp.135-143
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• 1988

The treatments of $H_2O_2$ were more effective on the degradation of difficult digestible materials by increasing the treatment concentration and adjusting the pH to alkaline. The smaller particle size of rice straw was, the more these effect. $2N_2CO_3{\cdot}3H_2O_2$, didn't need to adjust on pH, but the effect of treatment was lower than $H_2O_2$(pH 11.5) treatment. Lignin and hemicellulose content were decreased by the alkaline peroxide treatments. The fermentation of rice straw which pretreated with alkaline peroxide, the content of total nitrogen and ash increased. And NDF, hemicellulose and lignin were decreased, and ADF and cellulose decreased as the lower concentra­tion of treatment. The digestibility of rice straw which treated alkaline peroxide was increased with increasing the treatment concentration. The treatment of 12% $H_2O_2$(pH 11.5) and 12% $2Na_2^-CO_3{\cdot}3H_2O_2$ increased the digestibility from 31.1% to 89.4% and 76.8% compared with nontreated rice straw, respectively. The digestibility of fermented rice straw which pretreated with alkaline peroxide was effectively increased as the pretreatment concentration was low. Semi-dry treat­ment of $H_2O_2$ decreased the ADF and cellulose, and exhibited the 57.5% of digestjbility. Fer­mentation of rice straw which semi-dry treated with 4% $H_2O_2$, increased the digestibility from 33.4% to 63.4% compared with control.

• Journal of Veterinary Clinics
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• v.24 no.2
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• pp.99-103
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• 2007

The antibacterial efficacy of 0.1% (w/v) chitosan solution against Staphylococcus intermedius isolated from a dog with superficial pyoderma was evaluated in vitro and in vivo. The exposure time for the 0.1% chitosan solutions at different pH to be able to eliminate the bacterial cells and the effect of pH of the solutions on antibacterial activity was tested at the same time in vitro. The antibacterial activity of chitosan was compared to other antibacterial agents including 2.5% benzoyl peroxide, 0.5% chlorhexidine acetate, 0.1% chitosan solution combined with 2.5% benzoyl peroxide and chitosan combined with 0.5% chlorhexidine using a modified detergent scrub quantitative technique in 10 adult mongrel dogs in vivo. They were able to eliminate a number of bacteria after the exposure time of 10 minutes at varying degrees according to the pH of the solutions. The antibacterial activity of chitosan was inversely affected by pH with higher activity at lower pH value. The 0.1% chitosan solution was also efficacious against Staphylococcus intermedius in vivo. The combinations of chitosan with benzoyl peroxide and with chlorhexidine were shown to exert higher activity when compared to those of chitosan alone and benzoyl peroxide or chlorhexidine alone. The 0.1% chitosan solution was considered to be efficacious against Staphylococcus intermedius isolated from a dog with superficial pyoderma in both in vivo and in vitro and have a potential for the clinical applications in the treatment or pyoderma in dogs.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.114-120
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• 1985

This study was carried out to investigate the storage stability of Yackwa (a Korean fried cake made from wheat flour, honey and 20% oil), with the variation in frying oils (soybean oil of fresh or heat-treated corn oil and rapeseed oil) and storage conditions (temperature, humidity and in dark or under fluorescent light) for 20 weeks period. In $5^{\circ}C$ storage, acid and peroxide values increased slowly, showing the peroxide value of 20 meq/kg after 13 weeks. In $40^{\circ}C$ storage, acid and peroxide values increased remarkably. The product became harder at storage humidity of 25% and softer by moistening at storage humidity of 80%. Acid and peroxide values of Yackwa from corn, rapeseed and soybean oils increased with storage period, to a different extent. The values of fluorescent groups, especially rapeseed oil group, were higher than those of control groups and the heat-treated oil groups were higher than those of fresh oil groups. Sensory scores for rancid flavor were gradually increased with the storage period in all groups. There was no significant difference with the kinds of frying oils, storage conditions and heat treatment. Correlation of sensory scores with acid values was positive throughout whole storage period, with low ${\gamma}-values$. Its correlation with peroxide values was positive up to 6th week but negative at 9th week of storage.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 2002.10b
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• pp.341-342
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• 2002

Although vegetable oils provide good lubricity, they still need optimization by certain additive technology for practical applications. ZDTP improve antiwear properties of vegetable oils. However the additive performance depends on quality of the base Oil. Antioxidants were applied to prevent the auto-oxidation of vegetable oils. Good synergistic effect of anti-wear and antioxidant additives was confirmed.

• Journal of dental hygiene science
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• v.13 no.2
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• pp.165-173
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• 2013

The purpose of this study was to evaluate the surface change after 15% carbamide peroxide home bleaching to various restorative materials (composite resin [CR], resin modified glass ionomer [RMGI] and glass ionomer [GI]) and to observe the effect of surface condition of the materials on re-staining. Three esthetic restorative materials (Filtek Z250, 3M, USA; Fuji II LC, GC, Japan; Fuji II, GC, Japan) were used in this study. Twenty specimens per material group were made and divided into two groups (bleached and control). The specimens were immersed in coffee after applying bleaching agent. The color change and surface roughness were measured before and after bleaching and after immersion in coffee. The data were analyzed with SPSS 18.0. The results were as follows: 1. The color of all experiment groups was significantly changed after bleaching (p<0.05). RMGI was the greatest value of ${\Delta}E^*$ and ${\Delta}L^*$. GI and CR groups were in ordering (p<0.05). The ${\Delta}a^*$ value was decreased GI, RMGI and CR. RMGI was only significantly decreased in ${\Delta}b^*$ value (p<0.05). 2. The surface roughness before and after bleaching was significantly different on CR, RMGI and GI (p<0.05). 3. After staining with coffee, the value of ${\Delta}E^*$ was increased in GI, RMGI and CR, furthermore GI and RMGI showed significant difference in the bleaching groups (p<0.05). The ${\Delta}L^*$ value of GI and RMGI was significantly decreased. 4. The change of surface roughness after staining was not significantly different in all groups (p>0.05). The maintenance of color stability in esthetic restorations is one of the most important properties. Tooth whitening is for the aesthetic. Therefore, dental professionals should notice to patients about re-staining after tooth whitening. They should give an instruction that how to prevent and which kinds of agents could be stained.