• Journal of the Korean Society of Food Culture
• /
• v.20 no.2
• /
• pp.221-231
• /
• 2005

We investigated the physico-chemical and sensory characteristics of Kimchi made with red pepper that was washed and mashed. The pH of juice from Kimchi made with red pepper powder was the highest on the day of Kimchi preparation. In the case of Kimchi made with mashed red pepper, the pH of juice and liquid was lower than that of other samples. A similar decrease in pH of juice and liquid was observed up to the second week of fermentation, but the significant difference between both samples wasn't found. The total acidity of Kimchi with mashed red pepper was significantly increased during early fermentation, but was similar during the second week, compared with that of Kimchi with red pepper powder. From the third week of storage, both juice and liquid from Kimchi made with red pepper powder was relatively increased. L and a value of liquid was highest in the case of Kimchi made with mashed red pepper, but b value was lowest during fermentation. In the case of organic acids, acetic acid and lactic acid contents were increased in Kimchi made with mashed red pepper while fermentation progressed. In addition, citric acid content was constant up to the second week in Kimchi made with mashed red pepper but from the third week wasn't detected in both Kimchi made with mashed red pepper and Kimchi made with red pepper powder. In the case of QDA(Quantitative Descriptive Analysis) profiles, the values of Kimchi made with mashed red pepper were significantly higher than those of Kimchi made with red pepper powder in respect to redness, pungency and fresh flavor immediately after the preparation of Kimchi and during the second week of fermentation, but during the fifth week the values were higher in respect to redness and fresh flavor of Kimchi. Appearance and overall acceptability was remarkably increased in Kimchi made with mashed red pepper, compared with that of Kimchi made with red pepper powder immediately after pickling, during the second and the fifth week of fermentation. Therefore, these results indicate that mashed red pepper increased more citric acid content, L and a value of Kimchi in comparison with red pepper powder, resulting in the good effects on overall acceptability due to the significant increase of redness and fresh flavor.

• Korean Journal of Poultry Science
• /
• v.42 no.4
• /
• pp.347-352
• /
• 2015

This study was first conducted to investigate the effect of post-mortem storage time of chicken meat on the quality of chicken breast, and to determine whether the current grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is appropriate or not at meat processing plants. Different methods such as freshness, lightness ($L^*$), total number of microbes, 2-thiobarbituric acid reactive substances (TBARS), shear force and cooking loss were performed. Forty samples of different PM time (0~4 day) of chicken meat were stored in the refrigerator ($3^{\circ}C$). As a result of comparing the chicken meat of 2 day and 3 day PM, torrymeter value was 6.9 and 7.0, respectively. The other values are also as follows: lightness ($L^*$) 60.22 and 60.51, total number of microbes 4.20 and $4.31log_{10}CFU/g$, TBARS value 0.056 and 0.071 mg MDA/kg, shear force 1.43 and $1.59kg/cm^2$, and cooking loss 17.24 and 15.66%, respectively. As a result, these two groups were not significantly different (P<0.05). TBARS value of the chicken meat of 4 day PM was 0.088 mg MDA/kg which is significantly higher compared to 2~3 day PM (P<0.05). Thus, the result of the study suggests that using the chicken meat within 3 day PM is also possible. If the grading rule that is 'using the chicken meat within 2 day post-mortem (PM)' is changed to 3 day PM, it will allow processing plants and distributors to more flexibly use or distribute chicken meat.

• Korean Journal of Environmental Agriculture
• /
• v.25 no.2
• /
• pp.138-146
• /
• 2006

To understand the status of water quality and work out a suitable countermeasures in Seonakdong watershed which has poor agro- environmental condition because of severe point and non-point source pollution by popularized city and near sea, we investigated the pollution sources and water quality from '03 and '05 and the result were mapped with GIS and RS for end-users's convenient comprehense and conjunction of water quality and geological data. The most degraded tributary was Hogeo stream which was affected directly by highly popularized Gimhae city, the main pollution source of the watershed. The pollution of tributaries in watershed increased the T-N of main body that reached over 4 mg/L during dry season. Pyeonggang stream and the lower part of main water way were suffered from high salt contents induced near sea and the EC value of those area were increased to 2.25 dS/m. The delivered loads of T-N and T-P were largest in Joman river as 56% and 61% of total delivered loads 1mm tributaries because of lots of stream flow. When Management mandate for irrigation water in Seonakdong river watershed was mapped for estimating integrated water quality as the basis of classification of EC and T-N contents in water, Hogeo and Shineo catchments were showed the requiring countermeasures none against nutrients hazard and Pyeonggang catchment was the vulnerable zone against nutrients and salts hazard. As the result, Seonakdong watershed had very various status of water quality by characteristics of catchments and countermeasures for improving water quality and crop productivity safely should changed depend on that.

• Korean Journal of Environmental Agriculture
• /
• v.25 no.2
• /
• pp.164-169
• /
• 2006

This study was conducted for 10 days from 17 July to 26 July in 2005 to measure the amount of xylem sap flow under short-term variation of soil moisture regimes at -20 kPa, -50 kPa and -80 kPa in eight-year-old 'Fuji'/M.9 apple trees with different fruit loads. Fruit load was adjusted as three different treatments with standard (100%), 1/2 times (50%) and 2 times (200%) on the basis of optimum fruiting number per tree as the standard fruit load of Fuji cultivar. Trees with standard fruit load during the experimental period showed higher xylem sap flow at -50 kPa of soil moisture regimes than those of trees with 1/2 times and 2 times fruit load. Trees with 1/2 times and 2 times fruit load had similar patterns of the diurnal changes of xylem sap flow, vapor pressure deficit (VPD), and maximum evapotranspiration (ETm). However, trees with 2 times fruit load at -50 kPa and -80 kPa of soil moisture regimes produced lower amount of xylem sap flow than ETm. Trees with standard fruit load produced $1.06{\sim}3.93$ L/tree more amount of xylem sap flow than ETm at all soil moisture regimes. But xylem sap flow of tees with 2 times fruit load had 21% lower at -50 kPa and $31{\sim}36%$ lower at -20 kPa and -80 kPa of soil moisture regimes, respectively than that of trees with standard fruit load. Shoot growth and leaf area were significantly the highest in trees with standard fruit load while those of trees with 2 times fruit load recorded significantly lowest. Leaf water potential of trees with standard fruit load was lower than that of trees with 1/2 times and 2 times fruit load. It indicated that tees with standard fruit load had higher water use for transpiration than other treatments and tees with 2 times fruit load received more stress for the transpiration process under low soil moisture regimes. Consequently, 'Fuji'/M.9 apple trees, the fruit load and soil moisture should be maintained optimum to increase xylem sap flow and transpiration during higher growth period.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.22 no.2
• /
• pp.137-144
• /
• 2002

To investigate the short-term effects of N-supply form ( $NO_3\;^-$ or $NH_4\;^+$ ) and their level (0.2, 1.0 and 6.0 mM) on N assimilation and C metabolism were examined in perennial ryegrass (Lolium perenne L.). The increase in shoot fresh for $NH_4\;^+$-fed plants much less than $NO_3\;^-$ fed ones. Nitrate concentration in $NO_3\;^-$ -fed plants tended to increase with increasing the supply level, while that of $NH_4\;^+$-fed plants was nearly stable. Nitrate reductase activity (NRA) responded much quickly, showing a proportional increase within 24 h of feeding. NRA in $NO_3\;^-$ -fed plants at 72 h increased by 13.7, 40.3 and 84.0% in 0.2, 1.0 and 6.0 mM $NO_3\;^-$ -fed, but it was not changed in$NH_4\;^+$-fed plants regardless of the supply level. After 72 h of treatment the sugar accumulation in the plants supplied with 0.2 and 1.0 mM -$NH_4\;^+$fed was remarked. After 72 h of feeding, fructan hydrolysis was observed in all levels fur $NH_4\;^+$-fed plants, but only in 6.0 mM for $NO_3\;^-$ -fed plants.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.22 no.2
• /
• pp.145-152
• /
• 2002

To compare the Carbon metabolic response to high temperature stress in Zoysiagrass [Zoysia matrella (L.) Merr.] and Creeping bentgrass (Agrostis palustris Huds) with respect to heat tolerance, C metabolites were determined from April to September. Sampling was carried out on an established golf course (Muan Country Club, Chonnam, Korea). Shoot mass(g Dry weight per hole cup) of creeping bentgrass started to decrease from June and recovered from August whereas that of zoysiagrass was less varied. Chlorophyll content in creeping bentgrass was significantly higher than zoysiagrass until July, and then decreased by 43% from July to August. Zoysiagrass contained higher soluble sugar than creeping bentgrass throughout experimental period. Soluble sugar in zoysiagrass increased about 58% from April to May, and less varied until August. Soluble sugar in creeping bentgrass slightly increased until July and sharply decreased at August. Starch concentration in zoysiagrass continuously decreased to September after a significant increase from April to May. A remarkable fluctuation in both starch and fluctuation concentration was observed between June and August showing high accumulation for June to July and high degradation for July to August. These results suggest that through creeping bentgrass suffers much severely from high temperature stress than zoysiagrass especially June to August. An active accumulation and degradation in nonstructural carbohydrate in creeping bentgrass during this period might be associated with heat stress.

• Korean Journal of Food Science and Technology
• /
• v.42 no.1
• /
• pp.90-96
• /
• 2010

In this study, the anti-oxidant, anti-tumorigenic, anti-hypertensive, anti-thrombic, anti-diabetic, and anti-inflammatory properties of 18 different species of genus Pleurotus were investigated. In addition, the amino acid, $\beta$-glucan, and polyphenol content were also measured. All species contained more than 20 mg% of polyphenol with the highest contents found in Pleurotus cornucopiae var. citrinopileatus (yellow pleurotus) ($39.13{\pm}0.82\;mg%$). The $\beta$-glucan contents was also the highest in yellow Pleurotus ($37.67{\pm}0.22%$) followed by Won-Hyeong1 (C, $28.75{\pm}0.61%$) and Jang-an PK (A, $27.95{\pm}0.33%$). The yellow Pleurotus exhibited the highest antioxidant activity as assessed by the DPPH scavenging rate with an $IC_{50}$ value of $2.94{\pm}0.44\;mg/mL$. Ethanol extracts from the yellow Pleurotus treated at 1% concentration showed cytotoxic activity up to 36.9% in the human embryonic kidney 293T cell lines. The yellow Pleurotus also showed the highest inhibitory effects on ACE activity ($60.52{\pm}0.2%$). Finally, the yellow Pleurotus exhibited anti-diabetic and anti-inflammatory properties as shown by inhibition of $\alpha$-amyloglucosidase activity ($50.5{\pm}0.8%$) and nitric oxide production ($68.4{\pm}0.3%$). Taken together, our data indicate the yellow pleurotus is a promising functional food ingredients.

• Journal of Bio-Environment Control
• /
• v.15 no.2
• /
• pp.125-137
• /
• 2006

Pleurotus eryngii is one of the most promising mushrooms produced on the domestic farms. The quality as well as quantity of Eryngii is sensitively affected by micro climate factors such as temperature, relative humidity, $CO_2$ concentration, and light intensity. To safely produce high-quality Eryngii all the yew round, it is required that the environmental factors be carefully controlled by well designed structures equipped with various facilities and control systems. At the commercial mushroom cultivation houses of permanent frame type (A, B), this study was carried out to find out reasonable range of each environmental factor and yield together with economic and safe structures influencing on the optimal productivity of Eryngii. This experiment was conducted for about two-year ken Nov. 2003 to Dec. 2005 in cultivation house. Ambient temperature during the experiment period was not predominantly different from that of a normal year. The capacity of the hot water boiler and the piping systems were not enough. Because the capacity of electric heater and air circulation were not enough, air temperatures in cultivation house before improvement of system were maintained somewhat lower than setting temperature, and maximum air temperature difference between the upper and lower growth stage during a heating time period was about 5.1. But the air temperatures after system improvement were maintained within the limits range of setting temperature without happening stagnant of air. Air temperature distribution was generally distributed uniform. Relative humidity in cultivation house before , improvement was widely ranged about $44{\sim}100%$. But as the relative humidity after improvement was ranged approximately $80{\sim}100%$, it was maintained within the range of relative humidity recommended. And $CO_2$ concentration was maintained about $400{\sim}3,300mg{\cdot}L^{-1}$ range. The illuminance in cultivation house was widely distributed in accordance with position, and it was maintained lower than the recommended illuminance range $100{\sim}200lx$. The acidity of midium was some lower range than the recommend acidity range of pH $5.5{\sim}6.5$. The yield was relatively ununiform. In case of bottle capacity of 1,300cc, the mushroom of the lowest grade was less than 3%. The consumption electric energy was quite different according to the cultivation season. The electric energy consumed during heating season was much more than that of cooling season.

• Korean journal of applied entomology
• /
• v.46 no.3
• /
• pp.343-348
• /
• 2007

To assess the environmental risks of transgenic chili pepper with PepEST gene on non-target organisms before it exposes to the agro-ecosystem environments, we conducted the three sets of green peach aphids (Myzus persicas S.) life table experiment under laboratory conditions (Temp. $25^{\circ}C$, R.H. 50-70%, Photoperiod L16 : D8) in series during 2005-2006. We measured the net reproductive rate ($R_0)^*$, the intrinsic rate of increase ($r_m$), the mean generation time ($T_c$), $fecundity^*$, life span, and reproduction period between non-transgenic chili peppers and transgenic chili peppers, respectively. The life span of green peach aphids from three sets was 31, 27, 25 days, and the period of life span was similar to the general average length of green peach aphids, 25-29 days. Although the first reproduction of transgenic pepper was similar to the non transgenic pepper (P>0.05), the fecundity and the net reproductive rate ($R_o$) by using Jackknife method of transgenic pepper were lower than those of non transgenic pepper (P<0.05). Conclusively, we observed the adverse effect from our results but we should execute further experiments to confirm the results at the fields with the similar way.

• Korean Journal of Medicinal Crop Science
• /
• v.13 no.6
• /
• pp.261-267
• /
• 2005

Alcohol metabolizing and antioxidant activity of Mentha species were investigated in rat liver. Fifty six Sprague Dawley rats were randomly divided into seven groups such as normal (ethanol excluded), negative control (40% ethanol (10 g/kg of body weight/day) fed), positive control (1 g Silymarin/kg of body weight/day with ethanol fed), two Mentha viridis extracts (0.2 g & 1 g M. viridis methanol ext./kg of body weight/day with ethanol fed) and two M piperita extracts (0.2 g & 1 g M. piperita methanol ext./kg of body weight/day with ethanol fed) groups. After 2 weeks, rats were sacrificed under ether. The activities of alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), catalase (CAT), manganese superoxide dismutase (Mn-SOD), glutathione peroxidase (GAH-px) and the content ofthiobarbituric acid reactive substance (TBARS) in the rat livers and the activity of glutamate pyruvate transferase (GPT) in serum were evaluated. From the analyses, 1 g M. viridis and 0.2 g M. piperita administrated groups showed higher ADH and ALDH activity than the other groups. Groups fed with 0.2 g and 1 g M. viridis ext. and 0.2 g M. piperita ext. showed higher CAT activity than the other groups. All the Mentha extract fed groups exhibited more effective in recovering Mn-SOD, GSH-px and GPT acitivities to a similar degree of normal group. TBARS contents of two M. viridis ext. fed group and 0.2 g M. piperita ext. fed group were higher than those of the other groups. M. viridis extract fed groups showed more effective in CAT and Mn-SOD activities than M. piperita extract groups at p < 0.05. Finally, it is concluded that both Mentha species have alcohol metabolizing and antioxidant activity and M viridis is more effective than M. piperita.