• Korean Journal of Food Science and Technology
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• v.12 no.1
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• pp.34-40
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• 1980

In order to establish the frozen storage method of pork and contribute to the stabilization of pork price physicochemical changes and sensory evaluation of pork, stored at $-20^{\circ}C$ up to the period of 12 months, were analyzed every three months. The drip loss of frozen meat cuts was below 1% regardless of storage months. In the course of storage, pH of frozen half carcass rose a little, while that of meat cuts remained almost the same. WHC(water holding capacity) of frozen half carcass and meat cuts was in the range of $50{\sim}60\;and\;55{\sim}62%,$ respectively and VBN (volatile basic nitrogen) was about $11{\sim}18mg%,$ all of which did considerably change during the storage. TBA(thiobarbituric acid) value was not increased up to the 6th month of storage, but represented a considerable increase after the 9th month of storage, Both tenderness and juiciness of frozen pork were decreased after the 12th month of storage but the axxrptability of frozen pork to the consumers turned out fairly good.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.4
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• pp.313-320
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• 1984

In order to elucidate the oxidative stabilities of mackerel lipids, lipids were extracted from ordinary muscle, dark muscle, skin (including subcutaneous adipose tissue) and viscera, and then stored at $30^{\circ}C$. The changes of lipids were examined periodically by measuring peroxide value (POV), thiobarbituric acid (TBA), weighing method, acid value (AV) and iodine value (IV), Fatty acid composition of lipids was analyzed by GLC. The results obtained are summerized as follows: The velocity of lipid oxidation during the storage was differ from the extracting part of the sample. It was laster in skin, viscera, dark muscle and ordinary muscle in the order. Ratio of polar lipid fractions in total lipids was ranged from 5 to $15\%$, and the highest result was observed in dark muscle. Main fatty acids of the lipids were $C_{16:0}$ acid ($22.0{\sim}25.9\%$), $C_{18:1}$ acid ($22.3{\sim}26.7\%$) and $C_{22:6}$ acid ($9.6{\sim}13.4\%$), and $C_{22:6}$ acid content ($\%$) was the highest in lipid from dark muscle, and the lowest in lipid from skin. Monoenoic acid content ($\%$) was higher in the non-polar lipid than in the polar lipid, on the contrary. polyenoic acid content ($\%$) was higher in the polar lipid than in the non-polar lipid. Polyunsaturated fatty acids of the lipids, $C_{20:5}$ acid and $C_{22:6}$ acid, decreased predominantly with oxidation during storage, while saturated acids, $C_{14:0}$ acid and $C_{16:0}$ acid, increased predominantly. The polar lipid fractions were oxidized much faster than the non-polar lipid fractions.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.579-588
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• 2007

The effects of packaging methods on the quality of beef and pork jerky samples prepared Korean- style were investigated in terms of their pH, water activities ($A_w$), thiobarbituric acid (TBA) values, total bacterial counts, and sensory evaluations during storage at room temperature ($25^{\circ}C$ for 90 days. The jerky was subjected to plastic packaging and vacuum packaging conditions at $25^{\circ}C$ Levels of pH slightly decreased during storage (p<0.05), but there was no significant difference between the packaging methods. (p>0.05) Also, water activity decreased as storage time passed (p<0.05), and vacuum packaging resulted in a higher water activity value than plastic packaging. The hardness value of the jerky in plastic packaging was higher than that in vacuum packaging (p<0.05). In addition, hardness and TBA increased over the storage periods (p<0.05). The total bacterial counts in of the vacuum packaged jerky were lower than those of the plastic packaged jerky. The vacuum packaging treatments had higher scores than the plastic packaging treatments for all sensory traits. Based on our findings, we conclude that vacuum packaging is a more effective storage method than plastic packaging for jerky.

• Journal of Life Science
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• v.19 no.11
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• pp.1553-1561
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• 2009

This study investigated the biological activities and chemical characteristics of Monascus-fermented Korean red ginseng (MFRG). The comparative activities of water, ethanol, and methanol extracts from MFRGE and Korean red ginseng (RG) were tested in vitro of anti-oxidative models of linoleic acid peroxidation by thiocyanate and thiobarbituric acid (TBA) methods and DPPH ($\alpha,\alpha'$-diphenyl-$\beta$-picrylhydrazyl)radical scavenging activities. In addition, measurements of their bioactive total phenolic compounds and minerals, and extract yield, were obtained. The extract yield of each solvent extracted from MFRG and RG was aqueous by 6.58% and 5.83%, ethanol by 0.62% and 0.98%, and methanol by 1.27% and 3.04%, respectively. Total phenolic compounds were higher in all solvents extracted from MFRG than those from RG. Major mineral contents (ppm) of MFRG and RG were K by 16,936 and 22,386, Ca by 2,310 and 3,693, Mg by 2,703 and 2,647, respectively. The DPPH radical scavenging activities were higher in all solvents extracted from MFRG than those from RG, however, all these extracts exhibited a relatively low level of radical-scavenging activity compared to the butylated hydroxytoluene (BHT). In antioxidative activities determined by TBA method using linoleic acid peroxidation, 70% methanol extract from MFRG and RG showed the highest antioxidative activity at a concentration of 0.1%. These results may provide the basic data to understand the biological activities of bio-active materials derived from MFRG.

• Korean Journal of Food Science and Technology
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• v.37 no.1
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• pp.23-29
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• 2005

To investigate potential characteristics of clay minerals (illite, kaolin, zeolite, vermiculite, and bentonite) for food industry application, antioxidative properties of clay minerals, electron-donating ability (EDA), peroxide value (POV), and thiobabituric acid (TBA) were measured, and antimicrobial activity against several food spoilage microorganisms were evaluated by minimum inhibition concentration (MIC) method. Changes in components by cooking clay minerals added to stored rice were measured by GC-MS. DPPH (1,1-diphenyl-2-picrylhydrazyl) analysis results revealed bentonite has strongest EDA at 20.6%. Antioxidant activities measured based on POV were similar to DPPH results. Induction period of linoleic acid with vermiculite was longest among. TBA results revealed zeolite hasstrongest antioxidant ability. Growth inhibition against E. coli and S. aureuswas observed in illite, vermiculite, and zeolite. Aroma components indicated decrease in hex anal, pent anal, non anal, linoleate, stearic acid, and oleic acid when clay minerals were added to stored rice. These results indicate that several clay minerals have antioxidative and antimicrobial abilities and improve flavor profiles in stored rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.12 no.2
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• pp.62-65
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• 1983

As a new practical method for preserving freshness of fish, partially frozen storage has been reported to be useful in terms of K-value, TBA value, sensory evaluation etc. In order to develop a storage procedure to be used in place of cooled or frozen storage for the preservation of precooked fish food, partial freezing for up to two to three weeks was examined using baked mackerel. The criteria for evaluation were made according to the changes in volatile basic nitrogen (VBN), thiobarbituric acid (TBA) value, viable bacterial number, pH, color difference and sensory evaluation in fish muscle. The changes in TBA value of baked muscle during storage at $-3^{\circ}C$ differed slightly from those obserbed during cooled ($5^{\circ}C$) and frozen storage ($-20^{\circ}C$). Partial frozen storage ($-3^{\circ}C$) was effective in prolong an induction period of lipid oxidation during early storage. VBN of baked muscle tends to increase slowly while pH value was decrease during storage and there was no observed significant differences among three different storage condition. Viable bacterial number of the baked mackerel muscle stored at $-3^{\circ}C$ showed significantly less than that stored at $5^{\circ}C$, and similar to that stored at $-20^{\circ}C$ (the levels of $10^2/g$). Judging from the results of sensory evaluation and experimental data, partial frozen storage at $-3^{\circ}C$ seems to be effective as means of short-period preserving baked mackerel.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.463-469
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• 2003

This study was carried out to investigate the antioxidant activities of Dansam (S. miltiorrhiza). The Dansam (S. miltiorrhiza) was extracted with ethanol and methanol, and the extracts were fractionated with hexane, chloroform, ethyl acetate and butanol and water, in that order. The antioxidant activities of Dansam (S. miltiorrhiza) were determined by measuring the radical scavenging effects, using the 1, l-diphenyl-2-picryl-hydrazyl (DPPH) method. The electron donating ability was shown to be about 50% (IC50) at concentration of L-ascorbic acid, Dansam that reflected eliminatory effect by 50% were 9.48$\mu\textrm{g}$/$m\ell$, 8.28$\mu\textrm{g}$/$m\ell$, and l2.59$\mu\textrm{g}$/$m\ell$ respectively. According to the results of the above anti oxidation experiments, those for the group with the added Dansam showed a decreased oxidation, but the antioxidation increased with time. With a storage temperature of 60 C for 5 days, the acid value for the relative antioxidant activities were higher than in the Control group. The peroxide values for the relative antioxidant activities were also higher than in the Control group. The TBA values for the relative antioxidant activities were higher than in the Control group.

• Journal of the Korean Chemical Society
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• v.51 no.2
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• pp.178-185
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• 2007

Intermediate pentasil borosilicate zeolite-like materials have been crystallized by a novel method named steam-assisted conversion, which involves vapor-phase transport of water. Indeed, amorphous powders obtained by drying Na2O.SiO2.B2O3.TBA2O gels of various compositions using different boron sources are transformed into crystalline borosilicate zeolite belonging to pentasil family structure by contact with vapors of water under hydrothermal conditions. Using a variant of this method, a new material which has an intermediate structure of MFI/MEL in the ratio 90:10 was crystallized. The results show that steam and sufficiently high pH in the reacting hydrous solid are necessary for the crystallization to proceed. Characterization of the products shows some specific structural aspects which may have its unique catalytic properties. X-ray diffraction patterns of these microporous crystalline borosilicates are subjected to investigation, then, it is shown that the product structure has good crystallinity and is interpreted in terms of regular stacking of pentasil layers correlated by inversion centers (MFI structure) but interrupted by faults consisting of mirror-related layers (MEL structure). The products are also characterized by nitrogen adsorption at 77 K that shows higher microporous volume (0.160 cc/g) than that of pure MFI phase (0.119 cc/g). The obtained materials revealed high surface area (~600 m2/g). The infrared spectrum reveals the presence of an absorption band at 900.75 cm-1 indicating the incorporation of boron in tetrahedral sites in the silicate matrix of the crystalline phase.

• Journal of the Korean Applied Science and Technology
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• v.30 no.4
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• pp.761-769
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• 2013

This study used HPLC to analyze the contents of catechins, alkaloids, theanine, total phenolic compounds and antioxidant activities of commercial Hadong green tea leaves(Uzen, Sezak, Jungzak, Daezak). The content of catechins, alkaloids, theanine, total phenolic compounds were lower by water extracts than by 80% ethanol-water extracts. Total catechin and alkaloid contents in Uzen(172.33 mg/g, 30.80 mg/g) by 80% ethanol extract were the highest. Theanine contents of 80% ethanol-water extracts ranged form 55.36 to 37.48 mg/g of tea leaves. Total phenloic compounds contents of green tea were higher than Uzen. Antioxidative of green tea by DPPH, FTC, TBA method were higher than that Uzen.

• Food Science of Animal Resources
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• v.23 no.1
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• pp.46-49
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• 2003

Classwort (Salicornia herbacea L.), a halophyte, is a potential functional food resource in Korea. This study was conducted to determine the antioxidant activity of glasswort, as a functional food material, on the lipid oxidation of pork. To compare antioxidant effect of different parts of glasswort, samples such as dried ground leaves, stems, and roots of glasswort were prepared. The antioxidant activity was determined by the TBARS(Thiobarbituric Acid Reactive Substances) method. Freeze-dried leaves of glasswort at 0 day of storage had the lowest TBARS values, suggesting the highest antioxidant effect. But the antioxidative effect of freeze-dried leaves of glasswort was less than that of BHT. At 7 days after storage, however, the values were not different from oven-dried leaves. The oven-dried leaves at 14 days after storing should highest antioxidative activity. In conclusion, antioxidative effect of glasswort was apparently exhibited through measurement of TBARS. Antioxidative effect from ground leaf sample of glasswort harvested in coastal region was the highest, followed by root and stem samples. Glasswort had twice as high antioxidative effect as sea salt and bamboo salt.