• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.103-109
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• 2005

In order to investigate the correlation of the physical chemical characteristics of Kimchi with its sourness and overall acceptability, the pH, the reducing sugar content, the total microbial counts and the lactic acid bacterial counts of Kimchi were examined during fermentation at $5^{\circ}C$, $10^{\circ}C$ and $20^{\circ}C$. In regard to pH, the pH of the fermentation at $10^{\circ}C$ and $20^{\circ}C$ was nearly in inverse proportion to the sourness, whereas the pH at $5^{\circ}C$ fermentation was in less than inverse proportion to the sourness. For the correlation of the reducing sugar and the sourness, sourness and the reducing sugar showed an inverse proportion until the acidity reached $0.8\%\~1.0\%$. The reducing sugar content at $10^{\circ}C$ and $20^{\circ}C$ was nearly similar for the highest overall acceptability, whereas the reducing sugar content at $5^{\circ}C$ was higher than the reducing sugar content at $10^{\circ}C$ and $20^{\circ}C$. In the case of the total microbial count, the total microbial count and the sourness of Kimchi fermented at $5^{\circ}C$did not show the highest values at the same point, but the highest values of the total microbial count and the sourness of Kimchi fermented at $10^{\circ}C$ and $20^{\circ}C$ were the same at a point. Also, at a point for the best overall acceptability, the total microbial count at $10^{\circ}C$ fermentation was the highest, whereas those at $5^{\circ}C$ and $20^{\circ}C$ fermentation were similar. In case of the lactic acid bacterial count, the lactic acid bacterial count and the sourness at $5^{\circ}C$ fermentation did not show the highest value at the same point, but that at $10^{\circ}C$ and $20^{\circ}C$ fermentation did. For the correlation of the physical chemical characteristics with sourness, the sourness of Kimchi fermented at $5^{\circ}C$ showed a very significant correlation with acidity and it also showed a positive correlation with pH and the total microbial count, but these were not significant differences($\alpha$=$0.5\%$). At $10^{\circ}C$ and $20^{\circ}C$ fermentation, the sourness showed very significant correlation with all the physical chemical characteristics.

• Korean journal of food and cookery science
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• v.20 no.5
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• pp.436-443
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• 2004

The purpose of this study was to examine the physico-chemical and sensory characteristics of Kakdugi made with mashed red pepper. With regard to the pH of the Kakdugi, those of the juice from Kakdugi with red pepper powder and of the liquid with mashed red pepper were the highest and lowest immediately after preparation, respectively, but thereafter both slightly decreased, but were similar after the fifth week. Generally, the total acidity of Kakdugi liquid was the higher than that of Kakdugi juice. With regard to the L value, that of the Kakdugi juice was higher than that of Kakdugi liquid and that of Kakdugi with mashed red pepper washigher than that of Kakdugi with red pepper powder. From the third week, the 'L' values of all samples generally decreased. The 'a' value of the Kakdugi liquid with mashed red pepper during fermentation was highest During early fermentation, the juice of Kakdugi with red pepper powder showed a higher value than that of Kakdugi with mashed red pepper, but conversely, from the second week that of Kakdugi with mashed red pepper was higher than that of Kakdugi with red pepper powder. The 'b' value of the juice from Kakdugi with red pepper powder was highest until the second week, but from the third week that of Kakdugi with mashed red pepper was highest. With respect to the organic acids contents, those of citric, quinic and malic acids decreased, but those of lactic and acetic acids increased during fermentation progression. In addition, the citric, lacticand malic acids contents of the Kakdugi with mashed red pepper werethe highest, whereas that of quinic acid of the Kakdugi with red pepper powder was the highest. From the forth week, the acetic acid content of the Kakdugi with mashed red pepper was further increased. As a result of the sensory test, Kakdugi with mashed red pepper showed significantly higher values with regard to redness and fresh flavor, but in overall acceptability in the QDA, appearance and taste in the acceptance test. Therefore, our results indicate that mashed red pepper particularly increased the 'a' value and organic acid contents of Kakdugi compared to those of red pepper powder, leading to an increased overall acceptability.

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

• Food Science of Animal Resources
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• v.26 no.1
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• pp.64-69
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• 2006

This study was conducted to determine the effect of pH adjustment on physico-chemical characteristics of chicken breast surimi. The chicken breast meat was ground with distilled water, of which pH was then adjusted to 2.5 (T1), 3.0 (T2), 10.5 (T3) and 11.0 (T4) for surimi manufacture, respectively. Water content was higher in order of T4>T1>T3>T2 (p<0.05). Crude protein and crude fat were higher in T3 and T4 compared with T1 and T2 (p<0.05). $L^*$ values, myofibrillar protein and water holding capacity of T2 and T4 were higher than those of T1 and T3 (p<0.05). T4 had the lowest yield among the treatments (p<0.05). T1 was higher in yield and pH, whereas breaking force and deformation were higher in T1 (p<0.05). $a^*$ was higher in order of T3>T2>T4>T1 and $b^*$ was lower in T1 compared with other treatments (p<0.05). In textural properties, the chewiness values of T2 and T3 were higher than those of T1 and T4, the hardness was higher in order of T2>T3>T4>T1 (p<0.05). Cohesiveness and gumminess of T1 showed higher values than those of other treatments (p<0.05). In sensory evaluation, the note for appearance was higher in T2 than other treatments (p<0.05), however other traits were not significantly different (p>0.05). Therefore, the alkaline processing (T4, pH 11.0) would be recommended.

• Journal of Animal Science and Technology
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• v.46 no.2
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• pp.165-172
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• 2004

This study was conducted to investigate changes in physico-chemical characteristics of Hanwoo carcass according to different castration and slaughtering ages. Total 75 Hanwoo calves(average 4 months old) were randomly assigned to Control(bulIs). Treatment I. Il , III. or IV(castrated on 4. 9. 12. and 16 months of age, respectively) and slaughtered at 7. 9. 12, 16, and 28 months of age. Moisture contents in M. Longissimus dorsi of both Hanwoo bulls and steers were decreased as the slaughtering age increased. Moisture contents in all steer groups were significantly(P <0.05) lower(average 68.63%) than that in bulls(72.18%) at 28 months of age. Crude fat contents tended to increase as the slaughtering age increased. Crude fat contents in Treatment III(castrated at 12 months of age) at 28 months of age were 10.24% which was the highest among all steer groups. Crude protein contents in M. Longissimus dorsi of Hanwoo bulls were around 23% regardless of slaughtering age. Water holding capacity(WHC) of both bulls and steers tended to increase as the animals aged. Steers showed rapid increase in WHC after 16 months of age and showed higher(78.39%)) WHC than bulls(70.00%) at 28 months of age. Palmitic acid(CI8: 0) contents in Hanwoo bulls were increased as the slaughtering age increased(20.92 \longrightarrow 24.22%) whereas stearic acid(CI8: 0) contents were decreased(I8.l5 \longrightarrow11.32%). Oleic acid(CI8: I). a major unsaturated fatty acid. significantly(P <0.05) increased(25.59 \longrightarrow 37.90%) when slaughtering age of Hanwoo increased. Changes in fatty acid composition in Hanwoo steers were similar to those in bulls except oleic acid contents were higher and stearic acid contents were lower than bulls at 28 months of age.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.495-503
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• 2010

Analyses were conducted to estimate the effect of quality grade on the carcass characteristics, physico-chemical and sensory traits of Longissimus dorsi in Hanwoo. A total of 42,113 carcasses were selected on the basis of five quality grades (grade $1^{++}$, $1^+$, 1, 2, and 3) and an additional 258 samples of Longissimus dorsi were used to evaluate the beef quality. The increase in quality grade from grade 3 to grade $1^{++}$ was significant (p<0.05) for carcass weight (from 338.7 kg to 387.2 kg), backfat thickness (from 7.45 mm to 12.23 mm) and marbling score (from 1.09 to 8.31). In contrast, significantly decreased levels of meat color, fat color, texture and maturity were apparent with increasing quality grade (p<0.05). Increasing quality grade was also correlated with significant increases (p<0.05) in crude fat contents (from 3.57% to 25.68%) and water holding capacity (from 52.41% to 58.03), and a decrease of the Warner-Bratzler shear force from 8.29 kg to 2.83 kg. The highest $L^*$ value (41.53) and highest cooking loss (22.11%) were observed with grade $1^{++}$ and 3 beef, respectively. There was no difference observed on $pH_{24}$ (5.53 to 5.66) among the quality grades, which were within the normal range. Sensory evaluation experiments revealed that quality grades were associated with significantly altered (all p<0.05) tenderness, juiciness, flavor, and overall acceptability. The crude fat contents showed significant correlation with juiciness (r=0.59), tenderness (r=0.71), flavor (r=0.55), and overall acceptability (r=0.69). The lower sensory trait scores were related to higher WBs. Grade $1^+$ Hanwoo beef had a significantly higher WBs and lower fat contents when compared to grade $1^{++}$ Hanwoo beef (p<0.05).

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.4
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• pp.105-110
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• 2001

To provide successful treatment policy and to apply sources for establishing plan, municipal solid wastes quantity was investigated as physical and chemical characteristics from Sunchon city. Results are like following after checking out characteristics by seasons, type. The average specific weight of municipal solid wastes is $219kg/m^3$ for combustible wastes, $391kg/m^3$ for non-combustible. Food wastes of combustible wastes contained moisture of 38.1% as standard of moisture weight per real weight, 49.6% moisture is contained in non-combustible wastes except food wastes moisture. Moisture, volatile and ash are contented by 16.9%, 68.1% and 15.0% in combustible wastes except food wastes. That means combustible wastes are available a refuse incineration. The low calorific value of only combustible waste is 2,962kca1/kg that is good for refuse incineration.

• The Korean Journal of Ecology
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• v.25 no.5
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• pp.305-313
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• 2002

The physico-chemical characteristics of water and sediment, and structures of vegetation of the vascular hydrophytes were investigated in the West Nakdong River. Water quality was eutrophic according to the mean values and the ranges of water properties such as pH, DO, BOD, chlorophyll a, total nitrogen and phosphate, and other nutrients. A few cases were hypereutrophic for chlorophyll a level in summer. Soil reaction was weak acid. Composition of sediment was mainly sand except in SI(Sinan chideung) of which was mainly clay, and SU(Suan chideung) of which was mainly silt. Flora of vascular hydrophyte had 26 species and 1 variety comprising 16 families. Trapa japonica was dominant species in the sites of DU(Dunchido), GA(Garak chideung) and SU. Nymphoides peltata and Hydrocharis dubia dominated in DA and SI, respectively. Species diversity and evenness were relatively high in SI and SU but dominance was high in DA. After June, water lettuce(Pistia stratiotes) and water hyacinth(Eichhornia crassipes) were flowed from tributary to the river. Standing crop of macrohydrophytes was high in DA from April to August, but it showed maximum standing crop (445g·dw/㎡) in DU after disturbance by explosive growth of exotic plants in October. In comparison with those in 1985, total productivities in DU and GA decreased to 33.5%, and the reduction ratio of dominant species, Trapa japonica was 56.7%. Najas marina, N. minor, Myriophyllum spicatum and Nymphoides indica have disappeared ever since the Nakdong barrage was constructed in the Nakdong river. They were divided into three groups (GA-SU-DU, DA, SI) by cluster analysis. Introduction of the exotic species in this river caused decreasing of endemic plants including endangered species Euryale ferox and rare species Hydocharis dubia, and food plants for waterfowl such as Trapa japonica, Vallisneria asiatica and Potamogeton crispus.

• Journal of Life Science
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• v.19 no.9
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• pp.1271-1276
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• 2009

Unlike the traditional preparation method for Chungkukjang, we prepared Dua-Chungkukjang with soybean fermented at $40^{\circ}C$ after the soaking, germination and steaming process, and we studied the physico-chemical characteristics of Dua-Chungkukjang. Reducing sugar content in both traditional Chungkukjang and Dua-Chungkukjang increased sharply after 10 hr of fermentation, but it decreased slightly after that. Total nitrogen content in both traditional Chungkukjang and Dua-Chungkukjang increased slowly as fermentation took place. Total nitrogen content reached 3,500 mg% and 3,700 mg%, and soluble nitrogen compound reached 750 mg% and 1,800 mg% after 40 hr of fermentation, respectively. $\beta$-Glucosidase activity increased continuously as fermentation took place, and it reached 193, 223, 235 and 248 units in Dua-Chungkukjang while it reached 125, 178, 205 and 214 units in traditional Chungkukjang after 10 hr, 20 hr, 30 hr and 40 hr of fermentation. This means that $\beta$-Glucosidase activity in Dua-Chungkukjang was $1.2{\sim}1.5$ times higher than that in the control treatment, traditional Chungkukjang. Total isoflavone content was $101.44{\mu}g$/g and $365.92{\mu}g$/g for 10 hr of fermentation, and $225.98{\mu}g$/g and $441.37{\mu}g$/g for 40 hr in traditional Chungkukjang and Dua-Chungkukjang, respectively. Isoflavone content of Dua-Chungkukjang was 2-3.5 times higher than that of traditional Chungkukjang. Anthocyanin content also increased continuously as fermentation took place, and it reached 5.0 mg/g and 6.9 mg/g in traditional Chungkukjang and Dua-Chungkukjang after 40 hr of fermentation, respectively.

• Korean Journal of Ecology and Environment
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• v.36 no.1 s.102
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• pp.48-56
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• 2003

This study was evaluated about the seasonal variations of ecosystem in Nammae Reservoir based on the interrelation of physico-chemical characteristics, nutrients, chlorophyll a, b, c and standing crops of phytoplanktons. The amounts of chlorophyll a, b, c were respectively maximum (295 mg/, 9.5mg/l and 48mg/l) at station 1 in June and the standing crop of phytoplanktons was the highest ($1.7{\time}10^5$ cells/1) at stations 3 in July. The range of temperature was $7{\sim}37.4^{\circ}C$. The maxium of pH was $9.9{\sim}10.1$ at all stations in August, the minimum was 7 in September. SS was maximum (308 mg/1) at station 1 in June, while it was minimum (4 mg/l) at the same station in November. The maximal COD and DOC were 33 mg/1 and 16 mg/1 respectively at station 1 in June. As for phytoplanktons, Microcystis aeruginosa, blue-green alga in July${\sim}$August, Scenedesmus acutus, green alga in March${\sim}$May and November${\sim}$January and Cyclotella orientalis, Diatoms in October were dominant species. The amounts of P and Si were generally high in summer, they were low in autumn and winter. Nammae Reservoir assessed by trophic state index was eutrophicated and overtrophicated. These results indicated that Nammae Reservoir was faced with heavy water pollution. As preceding management for the basin of the Reservoir, it will have to be continually studied for an ecosystem reservation.