• Horticultural Science & Technology
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• v.28 no.3
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• pp.469-475
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• 2010

The major deterring factor of radish consumption is bitter and pungent tastes caused by glucosinolates. Recently kohlrabi was introduced in Korea and mainly cultivated in Jeju Island during winter. Since the texture and taste of kohlrabi are similar to radish, the kohlrabi is expected to substitute radish. This study was done to compare compositional quality between kohlrabi and radish. The kohlrabi contained less reducing sugars, cellulose and pectin than the radish. The kohlrabi had harder texture than the radish. The total amino acid content in the kohlrabi was 2.7-fold higher than that in the radish. Especially hydrophilic amino acids including aspartate, glutamate and arginine, were about 3-fold higher in the kohlrabi, suggesting that the kohlrabi was more palatable than the radish. The total contents of glucosinolates in the radish in inner and outer section were higher than those in the kohlrabi by 12.4- and 28.5-fold, respectively. In a sensory test, the kohlrabi was evaluated less bitter and pungent than the radish. The kohlrabi contained more glucoraphanin, an anticancer compound, than the radish. Furthermore, the sweetness of the kohlrabi was evaluated higher than that of the radish, though kohlrabi contained less reducing sugars, probably due to high contents of hydrophilic amino acids. In conclusion, the kohlrabi was evaluated as more favorable in taste and contained more functional compounds than the radish, and thus it can be a good replacement vegetable for radish.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.172-182
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• 2009

This study was to analyze characteristics based on tolerance and trophic guilds and to determine the level of total mercury in tissues of sentinel species, Zacco platypus at 3 sampling sites of the Mangyeong River in 2007. Total sampled fishes were 26 species and the most dominant species was Zacco temminckii (47%). Fish community analysis was resulted that eveness index and diversity index showed low value at S1. However, diversity index and richness index at other sites showed high. According to various guilds analysis, relative abundance of sensitive species was 70% and 42% at S1 and S2, respectively. While sensitive species were decreased (1%) and tolerant species were increased (60%) at S3. It was mainly carried to the impacts of wastewater treatment plants near the location. Relative abundance of insectivore species was decreased from up (S1) to midstream area (S3). In addition, chemical water quality, based on analyses of BOD, COD, TP, TN, EC, MPN and SS concentration showed similar trends. Qualitative Habitat Evaluation Index (QHEI) was averaged 164, judged as "good" habitat condition. Average concentrations of total [Hg] was 146.9 ${\mu}g$ $kg^{-1}$. In the muscles of total [Hg] was the highest, and then followed by kidney, vertebrae, liver, and gills. According to FDA standards (500 ${\mu}g$ $kg^{-1}$) of Korea, total [Hg] has not affected to the individual fish health.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.27-35
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• 2016

This study was conducted to investigate the quality characteristics of makgeolli containing aronia, (Aronia melanocarpa (0-1.9%)). After an initial decrease in the range of pH from 4.93-5.04 to 3.43-3.61 over a period of 6 days, it gradually increased until 14 days. As the fermentation proceeded, sugar contents and reducing sugar contents initially increased in majority of the samples, and subsequently decreased after 2 days. Total acidity contents increased until 6 days and then became higher as the content of aronia increased. Total acidity levels were within the range of 0.50-0.62%. After 14 days of fermentation, the alcohol contents ranged between 11.97 and 14.13%. Over the same time span, the amino acid content increased from a range of 1.57-2.22 to 5.86-6.92%. The microbial cell count and yeast colony count increased over the initial 4 days and then gradually decreased. Total polyphenol content and total flavonoid of aronia makgeolli were significantly higher than those of the control group. Based on the sensory evaluation, makgeolli with 1.3% aronia demonstrated the highest overall acceptance.

• Korean Journal of Food Science and Technology
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• v.42 no.2
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• pp.165-174
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• 2010

The effects of substituting whey protein isolate (WPI) for butter in the preparation of butter sponge cake were determined by objective and subjective tests. The specific gravity of cake batter, the cooking loss and moisture content of cake were all decreased with increasing amounts of WPI, whereas specific loaf volume was increased. With increasing WPI content, redness of crust and crumb, as well as lightness of crumb were increased, whereas lightness of crust, as well as yellowness of crust and crumb were all decreased. Hardness, chewiness, gumminess, adhesiveness and fracturability were increased significantly with increasing amounts of WPI, however, cohesiveness, springiness, and resilience were decreased. In the sensory evaluation, 20% WPI-substituted cake displayed scores similar to those of control. These results suggest that substitution of 20% WPI could be the best ratio for the preparation of butter sponge cake.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.461-465
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• 2016

In order to prevent the blackening and texture softening of heated shrimp, the pH was adjusted by soaking shrimps in acidic and alkali solutions, and their qualities were evaluated. The lightness of shrimps pretreated with 0.2% (w/w) citric acid and 0.05% (w/w) ascorbic acid solution increased by 20% compared to that of the control. The strength of mechanical hardness of shrimps soaked in acetic acid and phosphate solution (pH 6.0) was significantly higher ($1209g_f$) compared to that of untreated shrimp ($801g_f$; p<0.05), and the overall preference of texture was 0.4 points higher than that of the control in the descriptive sensory evaluation (p<0.05). In contrast, soaking in solution of pH 8 exhibited a weak texture hardening effect ($855g_f$). Additionally, the hardness of the heated shrimp after soaking at an adjusted pH of 4.0 increased to $4046g_f$, but the yield based on weight decreased to 38% compared to that of untreated shrimp (70%; p<0.05).

• The Korean Journal of Food And Nutrition
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• v.17 no.4
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• pp.374-381
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• 2004

This study was performed to characterize the mechanism of the acceleration of lactic acid fermentation in milk incubated with potato flour irradiated by ${\gamma}$-ray and two types of lactobacillus, Lactobacillus bulgaricus and Streptococcus thermophillus, and to examine its effect on the quality of yogurt by assessing the acidity of lactic acid, viscosity, free amino acid, and sensory. In lactic acid fermented in the presence of 0.5% (w/w) potato flour, its acidity was higher, its pH was lower, and its viscosity was increased than lactic acid fermented in the absence of potato flour. In the sample fermented with the mixture of S. thermophillus and L. bulgaricus, the acid production rate was highest. In the samples fermented with a single type of bacteria, the acid production rate of S. thermophillus was higher than that the L. bulgaricus. Fermented a single type of bacteria with potato flour, the lysine utilization rate of L. bulgaricus and S. thermophillus was high. L. bulgaricus produced a large quantity of glutamic acid whereas S. thermophillus consumed glutamic acid. In sensory evaluation of yogurt fermented with potato flour, the preference of texture was improved while its color, taste, flavor, and overall preference were decreased. The data suggest that L. bulgaricus stimulates the growth of S. thermophillus by providing free glutamic acid that is required by S. thermophillus and thus the addition of potato flour shortens the fermentation period of yogurt.

• Korean journal of food and cookery science
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• v.19 no.4
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• pp.454-462
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• 2003

Recently, the HACCP(Hazard Analysis Critical Control Point) system has been emphasized in food processing industries throughout the world. However, the system has, as yet, not been applied very well to domestic food industries. Due to the increase in the consumption of bakery products, more studies are required on the application of HACCP to establish the system in small-scale bakeries. This study was designed to provide basic data for setting management standards for HACCP, based on microbiological hazard evaluations of bakery products. Red bean paste filled breads, custard cream filled breads and cakes covered with fresh whipping cream were collected, and microbiological evaluations conducted on the raw materials, the manufacturing processes and potential hazards. The result showed the presence of coliforms in fresh cream of cakes and the soybean paste of soybean paste breads at levels as high as 105 CFU/g on the hazard analysis of the raw materials. Moreover, the general levels of bacteria and coliforms were over those of the standards during the intermediate fermentation and molding processes. Furthermore, high levels of coliforms were detected on the hands of the salesmen and bakers themselves. This suggests that the CCPs (Critical Control Points), such as fresh cream and red bean paste manufacturing process desperately require better management. There is also a requirement for education relating to personal hygiene for the production of hygienic bakery products and for the publics health.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.927-935
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• 2005

The objectives of this study were to investigate the soaking properties of the high-dietary fiber rice 'Goami 2'and to develop korean white Gruel prepared with Goami 2. With increasing soaking time at room temperature ($20^{\circ}C$), the water absorbing character of Goami 2 and Ilpum significantly increased during the first hour of soaking time, after which it remained constant. On the contrary, the hardness of Goami 2 and Ilpum significantly decreased with increasing soaking time until one hour, after which it remained constant. The properties of Korean white gruel were evaluated using two varieties of rice (Goami 2, Ilpum) and three blending times (10, 20 and 30 seconds respectively). The rice flour of Goami 2 for Korean white gruel showed a greater number of small particles (<20 $\mu$m) than that of Ilpum. Hunter a'and b'values of Korean white gruel prepared with Goami 2 were higher than that of Korean white gruel prepared with Ilpum. The consistency values on Bostwick consistometer of Korean white gruel prepared with Goami 2 were higher than those of Korean white gruel prepared with Ilpum. The texture of Korean white gruel was examined using a back extrusion rig. All of the rheological parameters of Korean white gruel prepared with Goami 2 were decreased with increasing blending time, while in llpum they were increased. In the sensory evaluation results, the overall acceptability of korean white gruel prepared with Goami 2 blended for 20sec showed the highest sensory scores and desirability.

• Korean journal of food and cookery science
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• v.20 no.1
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• pp.11-16
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• 2004

This study was conducted to increase the value of Aster glehni as a useful food resource. The Hunter L, a and b Values of Aster glehni leaves Were 34.23${\pm}$2.80, -10.59${\pm}$1.80 and 13.29${\pm}$2.51, respectively. The Shearing force and contents of tannin and dietary fiber were 4701.2g, 100.9ppm and 37.1％, respectively. The minerals identified in Aster glehni were Ca (6.93mg/kg), K (45.36mg/kg), Mg (1.70mg/kg), Fe (0.36mg/kg) and Na (1.26mg/kg). Aster glehni Kimchi was packed in polyethylene film (200g) and fermented at 20 and 4$^{\circ}C$. With regards to the color changes, the Aster glehni Kimchi fermented at 20$^{\circ}C$ showed greater increases in the Hunter L, a and b values than a 4$^{\circ}C$. The pH of the Kimchi decreased and acidity increased with storage time at both temperatures. The ascorbic acid contents decreased sharply with storage time and by about 85％ at 20$^{\circ}C$ after 5 days, and 73％ at 4$^{\circ}C$ after 30 days. The reducing sugar content also decreased with storage time at both 20 and 4$^{\circ}C$. The results of the sensory evaluation showed the optimum ripening times of the Aster glehni Kimchi to be 1∼3 days at 20$^{\circ}C$ and less than 20 days at 4$^{\circ}C$.

• Food Science of Animal Resources
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• v.27 no.4
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• pp.432-439
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• 2007

This study was performed to investigate the physicochemical properties and antioxidative activities of water or methanol extracts of Bokbunja (Rubus coreanus), and pork patties containing bokbunja extract at various levels. The total phenolic content of methanol extract (6.76 g/100 g, dry base) was higher than that of water extract (3.38 g/100 g, dry base). In addition, methanol extract had higher 1,1'-diphenyl-2-picrylhdrazyl (DPPH) radical scavenging activity than water extract at low concentrations (0.025-0.1%). However, no significant differences were found at high concentrations (0.2% or higher) (p>0.05). The DPPH radical scavenging activities of methanol and water extracts were 76.97% and 74.87% at 0.2% level, respectively. The lightness and yellowness values of pork patties containing Bokbunja extract decreased with increasing concentrations. The thiobarbituric acid reactive substances (TBARS) in pork patties with Bokbunja extract were lower than that of the control (p<0.05). The antioxidative activities increased with increasing concentrations of Bokbunja extract. In conclusion, Bokbunja extract might be used as a natural antioxidant in meat products, however levels lower than 3% will be required to prevent quality defects in pork patties.