• Korean Journal of Food Science and Technology
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• v.47 no.4
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• pp.419-424
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• 2015

The objective of this study was to investigate the physicochemical and antioxidant properties of a variety of commonly consumed commercial green tea. Green tea samples with the same commercial name produced at different regions were analyzed. High-grade tea samples showed higher values of lightness (L) and greenness (-a). Additionally, compared to other varieties of teas, high-grade tea samples showed higher levels of catechin, gallocatechin gallate (GCg), epicatechin gallate (ECg), theanine, and methylxanthines and a lower level of epigallocatechin (EGC). The antioxidant activity of green tea was also investigated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis (3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical assays. High-grade teas were observed to have higher antioxidant activities. The results of this study indicate that the catechin content, such as EGCg, GCg, and ECg levels, was found to positively influence the total antioxidant activity of green tea.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.719-722
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• 2011

The Daecha-12 and Yabukita varieties of powdered green teas were grown under 85% shade-cultivated condition, and their physicochemical properties were analyzed. Total catechin content was not significantly different but, non-gallated catechin content in Daecha-12 was significantly higher than that in Yabukita. Theanine (32%), caffeine (14%), lutein (15%) and total chlorophyll (28%) levels were significantly higher in Daecha-12 than those in Yabukita. The results of a color analysis showed that the lightness L-value of Yabukita was higher than that of Daecha-12 but, that the greenness negative a-value and b-values of Daecha-12 were higher than those of Yabukita. The Daecha-12 cultivar had lower catechin content but higher content of theanine, caffeine, theobromine, lutein, chlorophyll, and a negative a-value than those of the Yabukita cultivar. Thus, the Daecha-12 cultivar is suitable to prepare a high-quality powdered green tea product.

• The Korean Journal of Food And Nutrition
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• v.25 no.2
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• pp.407-412
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• 2012

Wild grass is edible, and it grows in the mountains or field areas. Wild grass has diverse biological effects, such as antiobesity, anti-cancer, antioxidant activities and immune stimulation. Currently, many studies are aimed at enhancing the efficacy of medicinal foods on biological activity using a bioconversion technology, including the fermentation process. In this study, the quality characteristics and antioxidative activity of the fermented wild grass was investigated. The antioxidant activity of fermented wild grass was assessed by various radical scavenging assays using DPPH(2,2-diphenyl-1-picrylhydrazyl), FRAP(ferric ion reducing antioxidant power), reducing power, and ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid)). Moisture contents of the fermented wild grass is $49.6{\pm}0.06%$. Contents of crude ash, crude protein, and crude fat were $0.65{\pm}0.01$, $0.65{\pm}0.04$, and $3.3{\pm}0.59%$, respectively. Moreover, fermented wild grass showed that the hunter's color values were 80.36(lightnees), 11.47(redness), and 44.53(yellowness), respectively. Total phenolic contents of the fermented wild grass was $1,185{\pm}159{\mu}g$ GAE(gallic acid equivalent)/g. The antioxidative activities of the fermented wild grass were significantly increased in a dose dependent manner. In addition, fermented wild grass did not show any cytotoxicity up to 500 ${\mu}g/m{\ell}$. However, the anti-adipogenic effect of the fermented wild grass extract was barely detectable. This antioxidant potential is partly due to the phenolic compounds that are present in the fermented wild grass extracts.

• The Korean Journal of Food And Nutrition
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• v.24 no.2
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• pp.159-165
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• 2011

This study was carried out to investigate the quality characteristics of pear jam containing fresh ginger(G1) and ginger powders; dried ginger powder(G2), freeze-dried ginger powder(G3), and hot-air dried ginger powder(G4). The moisture, crude protein, and crude ash content of the control group were significantly higher than those of the experimental groups (p<0.001, p<0.05, p<0.01). The pH of the dried ginger powder added jam(G2) was the lowest(p<0.05). Texture profile analysis found that the dried ginger powder added jam(G2) had the highest firmness, consistency, cohesiveness, and resistance to flow/viscosity among all samples(p<0.001). Regarding the spread-meter value of the pear jam, the control group (G1) and hot air-dried ginger powder added jam(G4) had the highest values. The dried ginger power added jam(G2) had the lowest value among the samples(p<0.01). Regarding the color values of the pear jam, the control group(G1) had the highest L and b values. Hot-air dried ginger powder added jam(G4), on the other hand, had the lowest(p<0.001). The opposite was true for a value: hot-air dried ginger powder added jam(G4) had the highest. From the sensory evaluation, a positive trend was observed for the appearance of the dried ginger powder added jam(G2)(p<0.001). For sweetness, the dried ginger powder added jam(G2) had the highest value. A positive trend was observed for the overall acceptability of the dried ginger powder-added jam(G2)(p<0.001). Therefore, the dried ginger powder-added sample(G2) seemed to be the most appropriate to make pear jam with high acceptability.

• Korean journal of food and cookery science
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• v.17 no.4
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• pp.316-322
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• 2001

The effect of onions on the quality characteristics of strawberry jam substituted with 50% fructo-oligosaccharide for sucrose was investigated. Strawberry jams with 10, 20, 30 and 40% onions in place of strawberry were prepared and evaluated for moisture content, pH, total acidity, color, spreadability, soluble solid content, reducing sugar, residual anthocyanin, instrumental texture and sensory characteristics. As the amount of onions increased, moisture content, total aridity, spreadability, soluble solid content, reducing sugar content and residual anthocyanin content of strawberry jams decreased, while pH increased. The lightness and redness decreased with addition of onions, but the yellowness increased. The sensory scores for strawberry jams decreased with the increase of onion content; however, strawberry jams with 10 or 20% onions showed fairly good scores.

• Korean journal of food and cookery science
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• v.15 no.2
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• pp.178-184
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• 1999

Physicochemical, microbiological, and sensory properties of corns irradiated by gamma-ray at 1.2 kGy, 10.1 kGy or 30.5 kGy were investigated every 40 days during the storage at 25$^{\circ}C$ and 50% relative humidity. The moisture content of irradiated corns decreased and crude lipid content increased during the storage. Acid values of the irradiated corns were not significantly different from those of the nonirradiated corns but acid values generally increased during the storage. TBA values of irradiated corns increased in proportion to the irradiation dose and to the storage period. Numbers of mesophilic and psychrotrophic bacteria in the nonirradiated corns and 1.2 kGy dose-irradiated corns were higher than those in the corns irradiated at 10.1 kGy and 30.5 kGy at the late storage. The number of yeasts and molds in the nonirradiated corns were higher than those in the irradiated corns during the storage. In Hunter's color, L values of irradiated and nonirradiated corns decreased with the storage period and b values of all groups decreased except the group irradiated at 30.5 kGy. In sensory evaluation, fresh corn odor of the irradiated group was significantly different from those of the nonirradiated one stored for only 0 day and 200 days but raw corn odor and acidic odor were not significantly different among the groups depending upon the radiation dose and storage period.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.291-298
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• 2010

We has been researched physicochemical, sensory and microbiological characteristics of salt-fermented shrimps after making them with different kinds of salts such as domestic or imported and purified or solar salt. Physicochemical characteristics of salt-fermented shrimps on color, salinity and pH which was made by 6 kinds of salt did not show any difference in the overall processing. However, in case of amino-N content, it showed the higher level of its contents at the process of Korean solar salt comparing to other. In case of microbiological, the total viable cells was detected most from the Australian solar salt during the initial stage of fermentation, but after 12-week of fermentation, the Chinese solar salt showed the largest number of total viable cells. Also, it found the Korean solar salt contained the lowest level of coliforms, while it found the highest level of coliforms contents in Chinese solar salt. However, there were no significant differences of microbiological characteristics from the salt-fermented shrimp made with 6 kinds of salt(p<0.05). As a result of sensory quality on salt-fermented shrimps, domestic salts was higher than imported. But there were no significant difference of sensory quality from the salt-fermented shrimps made with 6 different kinds of salt(p<0.05).

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.212-217
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• 2010

To enhance the quality of traditional Dasik, pollen Dasik containing brown rice flour fortified with 5, 10, 15 and 20% pollen powder were prepared, and their physicochemical properties were evaluated. Pollen Dasik possessed higher amount of mineral such as K and Ca than brown rice Dasik. The L value of pollen Dasik decreased with increasing pollen powder compared to brown rice Dasik, while the b value of pollen Dasik was increased with increasing pollen powder compared to brown rice Dasik(p<0.05). Hardness of pollen Dasik decreased with increasing amounts of pollen compared to the brown rice Dasik(p<0.05). Sensory evaluation on pollen Dasik preparewd with over 10% pollen showed the highest sensery evaluation value in overall preference.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.164-172
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• 2002

The objective of this study was to investigate the sensory and quality characteristics of Solsulgi containing different ratios of ingredients such as pine leaves power(1, 2, and 3%), sugar, and water. The results of sensory evaluation showed that Solsulgi containing 1% pine leaves powder had the higher scores in overall acceptability, color and flavor preference. In the textural analysis of Solsulgi, the springiness, chewiness, gumminess, and hardness were decreased by adding pine leaves powder. The hunter's color L value of Solsulgi was decreased by the increase of pine leaves powder. The more pine leaves powder was added, the redness and yellowness of Solsulgi were increased. The moisture content of Solsulgi was higher in the samples with 3% pine leaves powder than those with 1 %.

• Food Science of Animal Resources
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• v.22 no.1
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• pp.30-36
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• 2002

As meat consumption increases, consumers have demanded meat products containing functional ingredients which beneficial health effect rather than a normal food. The objective of this study was to investigate the physico-chemical and sensory properties of pork Bulgogi product(PB) containing different concentrations of ground ginseng such as 0%, 0.5%, 1.0% and 2.0%. The cooked PB containing ground ginseng had low TBA values when stored at 5$\^{C}$ for 7 days and showed high L and b values (CIE) in meat color when compared to those of control. The PB containing ground ginseng had lower scores in hardness than control, but there were no significant differences in cohesiveness, springness, and chewiness. In fatty acid compositions, the percentages of PUFA/SFA were highest in the PB containing 2% of ground ginseng. The sensory panels preferred PB containing ground ginseng in flavor, tenderness, juiciness and overall acceptability to those of control. In conclusion, the addition of ginseng enhanced flavor and palatability of PB without any adverse effect on meat quality.