• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.459-464
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• 1991

The mackerel meat was packed in square No 3B can, and thermally processed at $121.1^{\circ}C$ to reach Fo values of 5, 10 and 15. On heating at $121.1^{\circ}C$, pH and volatile basic nitrogen content increased markedly, and histamine was detected at concentrations of 3.98 mg/100g in raw meat, 10.45 mg/100g in Fo 5 sample, 7.54 mg/100g in Fo 15 sample, respectively. Total free amino acid content of mackerel meat decreased with increasing Fo values. Little changes were observed in free amino acid composition, but histidine decreased significantly during heat treatment. Degradation of inosine monophosphate was proceeded during preparation and thermal processing of samples, and trimethylamine oxide changed to trimethylamine almost equivalently. In changes of lipid components, peroxide and carbonyl values were increased markedly during heat treatment. When the sample was heated at the Fo values of 5 or higher, content of non-polar lipid(NL) was increased while that of polar lipid(PL) was decreased, and percentages of polyenes such as 22 : 6 decreased with increasing Fo values. The decomposition of polyunsaturated fatty acids in PL were much greater than those in total lipid and NL.

• Applied Biological Chemistry
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• v.36 no.5
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• pp.321-325
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• 1993

The anchovy-based powder for instant soup packed in twenty tea bag were repacked with (Product B) or without oxygen absorber (Product A) in laminated film bag $(PVDC/OPP,\;thickness:\;100.5\;{\mu}m,\;size:22{\times}18cm)$, and then stored at ambient temperature $(25{\pm}3^{\circ}C)$. Moisture, crude protein and crude lipid contents in anchovy-based powder for instant soup were 12.1%, 54.7% and 2.9%, respectively. Moisture content showed little changes during storage in both product (A) and (B). pH and saturated fatty acid such as 20 : 5 and 22 : 6 decreased, while volatile basic nitrogen content, carbonyl value, thiobarbituric acid value, monoenoic fatty acid such as 16 : 0, brown pigment formation and Hunter values increased during storage of product (A). But, these values showed a little change during storage of product (B). It is concluded that anchovy-based powder for instant soup can be handily and safely used during storage of 150 days.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.5
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• pp.834-839
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• 2002

To evaluate the antioxidative and antiaging effects of buchu in vivo system, 2% or 5% buchu diets were fed to ICR mice for 13 months and lipid peroxidation, protein oxidation, activities of antioxidative enzymes and total glutathione content on liver were measured. Hepatic TBARS contents did not show differences among diet groups, while buchu diet suppressed the protein oxidation significantly. SOD activities of control diet group decreased slowly after 7 month but buchu diet increased its activities steeply for first 3 month and continued to increase twice or three times higher than control diet during 13 month. While GSH-Px activities of control diet group were increased slightly with age, buchu diet increased its activities twice or three times higher than control. While catalase activities of control diet group were almost not changed with age, buchu diet increased its activities in both 2% and 5% diet groups. Total hepatic glutathione contents were gradually increased with age, while buchu diets In-creased its contents remarkably. According to this study, many antioxidative materials and sulfides compounds containing buchu seems to protect antioxidative systems on ICR mice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.583-587
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• 2006

Aqueous solutions of sugar alone or in the presence of lysine were gamma irradiated at 0, 5, 10, 20 and 30 kGy at room temperature. Absorbances at 284 nm as an indicator of intermediate stage of non -enzymatic browning reaction increased with irradiation dose in both the solution of sugar or lysine alone and sugar-lysine mixed solution. Absorbances at 420 nm as indicator of browning increased in the irradiated sugar-lysine mixed solutions although no browning was observed in the irradiated solution of sugar or lysine alone. The degree of browning of the irradiated sugar-lysine mixed solution increased with irradiation dose and was dependent on the type of sugar. For sugar-lysine mixed solution irradiated at 30 kGy, the browning had the following order of intensity: sucrose>fructose>arabinose>xylose>glucose. However, the sugar loss of irradiated sugar lysine mixed solution had a following order of intensity: glucose>fructose>sucrose>xylose>arabinose. The reducing power of the non-reducing sugar, sucrose, was produced by gamma irradiation. The present results indicated that gamma irradiation leads to a non-enzymatic browning reaction (carbonyl-amine reaction) in an aqueous system.

• Applied Chemistry for Engineering
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• v.26 no.5
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• pp.615-620
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• 2015

Polypropylene (PP)/bamboo fiber (BF) composites were fabricated by twin screw extruder in order to investigate effects of the compatibilizer on physical properties of PP/BF composites. The content of BF changed from 10 to 25 wt% and that of the compatibilizer was fixed at 3 wt%. Maleic anhydride grafted PP (PP-g-MAH) was used to increase the compatibility between PP and BF as a compatibilizer. Chemical structures of the composites were confirmed by the existence of carbonyl group (C=O) stretching peak at $1,700cm^{-1}$ in FT-IR spectrum. Considering the degradation and mechanical properties, the optimum extrusion conditions were selected to be $210^{\circ}C$ and 100 rpm, respectively. There was no distinct changes in melting temperature of the composites, but the crystallization temperature increased by $10-20^{\circ}C$ owing to the heterogeneous nuclei of BF. It was checked that the optimum BF content was in the range of 15-20 wt% from the results of tensile and flexural properties of the composites. The effect of the compatibilizer on mechanical properties was confirmed by SEM images of fractured surface and contact angles.

• Applied Chemistry for Engineering
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• v.26 no.2
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• pp.173-177
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• 2015

In this study, effects of both the grafted ABS-g-MAH and the added graphene oxide (GO) on the impact strength of polycarbonate (PC)/poly(acrylonitrile-butadiene-styrene) (ABS) blends were discussed. The PC/ABS blends and PC/ABS/GO composites were fabricated by using twin screw extruder with ABS-g-MAH as a compatibilizer. The ABS-g-MAH was prepared by melting extrusion of ABS and maleic anhydride (MAH) with DCP (dicumyl peroxide) as an initiator using twin screw extruder and the synthesis of ABS-g-MAH was confirmed by the presence of carbonyl group (C=O) peak at $1780cm^{-1}$ of FT-IR spectrum. According to the thermal, rheological, and impact properties of PC/ABS blends, 5 phr (parts per hundred resin) of compatibilizer was chosen as an optimum content for the PC/ABS/GO composites. It was observed that the thermal decomposition of ABS/PC/GO composites increased with GO contents, but there was no significant changes or a decrease in the impact strength. Also the composite fabricated by ABS/GO showed small increase in the impact strength. From the result of the dynamic rheometer to observe the processing properties, the complex viscosities of PC/ABS blend including the compatibilizer increased, but the complex viscosities of composites added GO were not changed.

• Korean journal of food and cookery science
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• v.18 no.4
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• pp.413-425
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• 2002

Quality characteristics of white bread added with lotus root powder(3, 6%) were investigated. Moisture content of white bread added with lotus root powder were higher than control. As the amount of added lotus root powder increased, the lightness, redness and yellowness of bread crust as well as the volume of the bread decreased, but the redness and yellowness of the crumb increased slightly. The content of free amino acids increased by the addition of lotus root powder and the major ones were L-glutamic acid, L-alanine, L-valine and threonine. The major flavor components were 2-methyl butanal and 3-methyl butanal, which were formed by the amino-carbonyl reaction in baking bread at high temperature. Aldehyde flavor components such as 2-ethylfuran, 2-butanedione and 3-butanedione were formed by yeast fermentation. Ethyl acetate and vinyl acetate also influenced the flavor of the bread. The addition of lotus root powder increased the hardness and fracturability, and decreased the gumminess, chewiness and cohesivenes of the bread. Sensory evaluation of white bread indicated that the addition of 3%, 6% lotus root bread enhanced the grain formation, color, mouth feeling, appearance, hardness, moistness, flavor and overall acceptability. Overall, the addition of 6% lotus root powder showed the best performance in the nutritional and functional aspects of the bread.

• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.116-122
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• 1977

The volatile flavor components of Kimchis were identified and the volatiles of fermented Kimchis (1.29% NaCl and 4.89 NaCl) were compared with those of raw Kimchi (1.29% NaCl). After the existence of carbonyls and sulfur compounds were confirmed by precipitation method, vacuum distillation was carried out to collect the volatiles of Kimchis in traps submerged in ice+salt, dryice-acetone and liquid N, respectively. The volatile flavor components were identified by GLC. The results were; 1. 17 volatile flavor components of Kimchis were identified by comparison of retention time with those of known compounds and acetaldehyde, acetone, ethanol, ethyl sulfide were positively identified by m.p., IR, UV, TLC. etc. 2. Ethanol was the most abundant volatiles of Kimchis and the content was much higher in fermented low salt Kimchi than in unfermented low salt Kimchi. 3. On the contrary, acetaldehyde and volatile sulfur compounds were reduced in fermented Kimchis, especially in fermented low salt Kimchi.

• Korean Journal of Weed Science
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• v.17 no.3
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• pp.325-333
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• 1997

Selection of pepper (Capsicum sp.) cultivars tolerant to acetolactate synthase (ALS)-inhibiting herbicides {imazethapyr, 2-[4,5-dihydro-4-methyl-4-(1-methylethyl)-5-oxo-1H-imidazol-2-yl]-5-ethyl-3=pyridine-carboxylic acid, and primisulfuron methyl 2-[[[[[4,6-bis(difluoromethoxy)-2-pyrimidinyl]amino] carbonyl]amino]sulfonyl]benzoate} was investigated. Pepper cultivars such as Red Top, Happy Dry, Golden Tower, and Hagyeorae showed relatively tolerant response to imazethapyr, while cultivars; Korea, Cheongyang, Oriental Glory, and Hanam were susceptible. Red Horn, Jopoong, Kwangbok, and Wangcho cultivars were tolerant to primisulfuron whereas Korea, Dahhong, Chamjoah, and Poongchon cultivars were susceptible. Determination of growth inhibition by ALS-inhibiting herbicides showed that the $I_{50}$ estimates of growth from the susceptible- and tolerant-cultivars were 0.075 and 0.20kg ai/ha for imazethapyr; 0.06 and 0.16kg ai/ha for primisulfuron, respectively. Furthermore, the $GR_{50}$ estimates of growth from the susceptible and tolerant cultivars were 0.05 and 0.20kg ai/ha for imazethapyr; 0.07 and 0.16kg ai/ha for primisulfuron, respectively. This result, based on the $GR_{50}$ and $I_{50}$ values, indicates that responses of pepper to ALS-inhibiting herbicides between tolerant- and susceptible-cultivars were different about 3- to 4-fold to imazethapyr, and 2- to 3-fold to primisulfuron.

• Polymer(Korea)
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• v.27 no.3
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• pp.210-216
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• 2003

4-Vinyl-1-cyclohexene diepoxide (VCE)/diglycidyl ether of bisphenol-A (DGEBA) epoxy blends with benzylquinoxalinium hexafluoroanti-monate were cured using an electron-beam technique. The effect of DGEBA content to VCE on cure behavior, thermal stabilities, and mechanical properties was investigated. The composition of VCE/DGEBA blend system vaned within 100:0, 80:20, 60:40, 40:60, 20:80, and 0:100 wt%. The cure behavior and thermal stability of the cured specimens was monited by near-infrared spectroscopy and thermogravimetric analysis, respectively. Also, the critical stress intensity factor ($_{4}$) test of the cured specimens was performed to study the mechanical interfacial properties. As a result, the decreases of short side-chain structure and chain scission were observed in NIR measurements as the DGEBA content increases, resulting in varying the hydroxyl and carbonyl groups. And, the initial decomposition temperature (IDT), temperature of maximum weight loss (T$\_$max/), and decomposition activation energy (E$\_$d/) as thermal stability factors were increased with increasing the DGEBA content. These results could be explained by mean of decreasing viscosity, stable aromatic ring structure, and grafted interpenetrating polymer network with increasing of DGEBA content. Also, the maximum $_{4}$ value showed at mixing ratio of 40:60 wt% in this blend system. in this blend system.