• Title/Summary/Keyword: physicochemical water quality

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Long-term Changes and Variational Characteristics of Water Quality in the Cheonsu Bay of Yellow Sea, Korea (천수만의 수질환경특성과 장기변동)

  • Park, Soung-Yun;Park, Gyung-Soo;Kim, Hyung-Chul;Kim, Pyoung-Joong;Kim, Jeon-Poong;Park, Jung-Hyeon;Kim, Sug-Yang
    • Journal of Environmental Science International
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    • v.15 no.5
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    • pp.447-459
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    • 2006
  • Long-term trends and distribution patterns of water quality were investigated in the Cheonsu Bay of Korea from 1983 to 2004. Water samples were collected at 4 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids (SS), chemical oxygen demand (COD), dissolved oxygen (DO) and nutrients. Spatial distribution patterns were not clear between stations but the seasonal variations were distinctive except COD, SS and nitrate. Twenty two year long-term trend analysis by PCA revealed the significant changes in water quality in the study area. Water quality during 1980's and early 1990's showed high SS, low nutrients and low COD which increased during the mid and late 1990's and early 2000's. Overall water duality in the Cheonsu Bay indicated the increase in nutrients and COD concentration.

The Dynamic of Phytoplankton Communities and the Biological Water Quality Assessment at Three Artificial Weirs in Downstream of Namhan-river (남한강 3개 인공보의 식물플랑크톤 군집 변동과 생물학적 수질평가)

  • Shin, Hyun-Joo;Lee, Ok-Min
    • Journal of Korean Society on Water Environment
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    • v.30 no.6
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    • pp.612-621
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    • 2014
  • Physicochemical factors and the phytoplankton communities in the downstream area of Namhan-River were investigated from June 2012 to November 2013. We also assessed water quality using biological water quality indices. Total nitrogen was 2.4 mg/L, total phosphorus was 0.04 mg/L, and biological oxygen demand was 1.1 mg/L. This resulted in a level 2 (Ib, good) water quality rating. A total of 259 phytoplankton taxa were classified, consisting of 26 families, two subfamilies, 64 genera, 222 species, 32 varieties, and five formas. Bacillariophyceae dominated during a1l seasons and at all sites. The dominant species were Aulacoseira granulata, Cyclotella meneghiniana, C. stelligera, Melosira varians, Cocconeis placentula var. lineata, Nitzschia palea, N. amphibia, Cymbella minuta, and Achnanthes convergens. The diatom assemblage index for organic pollution values was level A-D, and TDI was level B-D. P-IBI at most sites was at the M (moderate) level, but TSI was at the E (eutrophic) level. Most indices dropped from upstream to downstream.

Effect of Postmortem Phases on Lamb Meat Quality: A Physicochemical, Microstructural and Water Mobility Approach

  • Ge, Yue;Zhang, Dequan;Zhang, Huimin;Li, Xin;Fang, Fei;Liang, Ce;Wang, Zhenyu
    • Food Science of Animal Resources
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    • v.41 no.5
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    • pp.802-815
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    • 2021
  • To investigate the effect of postmortem phases on lamb meat quality, the physicochemical quality, microstructure and water mobility of oyster cut, short loin, knuckle and silverside muscles from Small-Tail Han sheep were evaluated in the pre-rigor, rigor mortis and post-rigor phases. Pre-rigor lamb meat had higher pH and water holding capacity (WHC), whereas lower CIE L*, b*, hue angle values than rigor mortis and post-rigor meat (p<0.05). The Warner-Bratzler shear force (WBSF) values were higher in rigor mortis short loin and silverside than their pre-rigor and post-rigor counterparts, pre-rigor short loin had lower WBSF value than its post-rigor counterpart (p<0.05). Muscle fibers shrank laterally and longitudinally during the onset of rigor mortis. Rigor mortis and postrigor lamb meat exhibited wide I-bands, dark A-bands, short sarcomeres and large inter-myofibrillar spaces. The shift of immobilized water to free water and repulsion from the intra-myofibrillar space to the extracellular space result in the increase of water loss in rigor mortis and post-rigor lamb meat. The results of the principal component analysis (PCA) indicated that rigor mortis and post-rigor lamb meat had similar quality properties but different from pre-rigor lamb meat. In conclusion, the lamb meat in the pre-rigor phase had good tenderness, color and WHC. The results of this research could provide some theoretical references for lamb meat production and processing.

Quality Change of Beverage Containing Muskmelon Vinegar and Concentrated Muskmelon Juice during Storage (참외 식초 및 농축액 함유 음료의 저장 중 품질 변화)

  • Lee Gee-Dong;Kim Suk-Kyung;Lee Myung-Hee
    • Food Science and Preservation
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    • v.12 no.3
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    • pp.223-229
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    • 2005
  • Response surface methodology(RSM) was used for monitoring the quality change of muskmelon beverage with storage temperature and time. Muskmelon beverage was prepared with the ratio of liquid fructose($11\%$), muskmelon vinegar($3\%$), concentrated muskmelon juice($1\%$) and refined water($84\%$). To examine physicochemical properties of muskmelon beverage, various factors such as color, brown color intensity and sugar content were determined using physicochemical methods. Physicochemical properties of muskmelon beverage were more affordable with the increased storage temperature. While, organoleptic properties decreased with the increased storage time and temperature. The result of this study indicated that the quality of muskmelon beverage was mostly influenced by the storage temperature. Muskmelon beverage showed the good score under $60^{\circ}C$ as a storage temperature.

The impact of overnight lairage on meat quality and storage stability of pork loin

  • Minwoo Choi;Dongheon Lee;Hyun Jung Lee;Ki-Chang Nam;Sung-Sil Moon;Jong Hyun Jung;Cheorun Jo
    • Journal of Animal Science and Technology
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    • v.66 no.2
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    • pp.412-424
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    • 2024
  • Lairage, a part of the animal welfare practices, has been known to mitigate pre-slaughter stress in animals. However, research investigating the relationship between lairage and pork meat quality remains scarce. In this study, we conducted a comparative analysis of the physicochemical quality and storage stability of pork from pigs subjected to immediate slaughter (CON) and those provided with a 24 h lairage before slaughter (LRG) over a 7-day storage period. The loins from 20 castrated pigs in each group, respectively, were collected at 1, 3, 5, and 7 days and used for analysis of meat quality and storage stability, including pH, meat color, moisture, water holding capacity, drip loss, cooking loss, shear force, fatty acid composition, lipid oxidation, antioxidant activity, and electrical resistance. Overall, there were no significant differences in physicochemical meat quality parameters between CON and LRG groups. Similarly, no differences were observed in the storage stability of pork including 2-thiobarbituric acid reactive substances, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and electrical resistance. However, the proportion of unsaturated fatty acids was significantly higher in LRG compared to CON. In conclusion, 24 h lairage for castrated pigs had limited impact on meat quality and storage stability but led to an increase in the unsaturated fatty acid proportion.

Water Pollution Status in Streams of Hongsung Area (홍성 지역 하천수의 수질현황)

  • 홍영호;조석형;전용진
    • Journal of environmental and Sanitary engineering
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    • v.16 no.1
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    • pp.27-33
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    • 2001
  • The purpose of this study on environmental investigation in Hongsung and Kwangchun streams is for the finding the degree of water quality. Physicochemical characteristics of streams are very important. However, that has not been investigated so for especially in stream of Hongsung area, And so, we tried to analyse BOD, TDS, $Cl^{-}$, anionic surfactant, pH, T-N and T-P of stream. The results were as follows. The pH for stream were generally in the range of 6.9 ~ 8.1 which is water quality for stander for stream, water quality of the Hongsung and Kwangchun upstream was not in problem but downstream showed somewhat high concentration in BOD, chlorine ion, T-P, T-N, and anionic surfactants. Especially BOD of Kwangchun downstream was higher than Hongsung downstream and concentration of T-P of Hongsung downstream was kept over 7 mg/liter regardless of inflow BOD ranging from 1.3 to 1.8 mg/liter.

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Geochemical evaluation of groundwater quality of Peshawar Basin, Pakistan

  • Akhter, Gulraiz;Mand, Bilal A.;Shah, Munir H.
    • Advances in environmental research
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    • v.10 no.1
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    • pp.43-57
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    • 2021
  • Evaluation of groundwater quality is vital due to its diverse use for several purposes. In the present study, groundwater quality and suitability from the Peshawar basin, Pakistan, were evaluated for drinking and irrigation purposes. The water samples were analysed for major cations (Ca, Mg, Na and K) and anions (chloride, bicarbonate and sulphate) along with other physicochemical parameters (pH, electrical conductivity, total dissolved solids, and total hardness). About 95% of the water samples were found to be within the WHO, US-EPA and Pak-EPA permissible levels for drinking purposes. Seventy percent (70%) of the water samples belonged to the hard water category. Irrigation water quality parameters, such as, chloride, residual sodium bicarbonate, sodium adsorption ratio, percent sodium, magnesium adsorption ratio, Kelly's ration and permeability index were evaluated which demonstrated that the groundwater was highly to moderately suitable for irrigation. A correlation study was conducted to find out the mutual associations among the variables. Piper diagram indicated the overall chemical nature of the study area was calcium-magnesium bicarbonate type. Cluster analysis revealed mutual apportionment of various parameters in the groundwater of the Peshawar basin, Pakistan.

Effect of Reservoirs on Microbiological Water Qualities in a Drinking Water Distribution System

  • Lee Dong-Geun;Kim Sang-Jong;Park Seong-Joo
    • Journal of Microbiology and Biotechnology
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    • v.16 no.7
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    • pp.1060-1067
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    • 2006
  • This study was undertaken to determine the effect of reservoirs on water quality and the distribution of pathogenic and indicator bacteria in a drinking water distribution system (total length 14km). Raw water, disinfected water, and water samples from the distribution system were subjected to physicochemical and microbiological analyses. Most factors encountered at each season included residual chloride, nitrate, turbidity, and phosphorus for heterotrophic bacterial distribution, and hardness, heterotrophic bacteria, sampling site, and DOC (dissolved organic carbon) for bacteria on selective media. No Salmonella or Shigella spp. were detected, but many colonies of opportunistic pathogens were found. Comparing tap water samples taken at similar distances from the water treatment plant, samples that had passed through a reservoir had a higher concentration of heterotrophic bacteria, and a higher rate of colony formation with 10 times as many bacteria on selective media. Based on the results with m-Endo agar, the water in reservoirs appeared safe; however, coliforms and opportunistic pathogenic bacteria such as Pseudomonas aeruginosa were identified on other selective media. This study illustrates that storage reservoirs in the drinking water distribution system have low microbiological water quality by opportunistic pathogens, and therefore, water quality must be controlled.

Comparison of Physicochemical Properties of Korean and Australian Wheat Flours Used to Make Korean Salted Noodles

  • Kim, In-Sook;Binns, Colin;Yun, Hon;Quail, Ken;Lee, Chi-Ho
    • Food Science and Biotechnology
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    • v.16 no.2
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    • pp.275-280
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    • 2007
  • The effect of using Korean wheat flour versus Australian wheat flour on noodle quality as a result of differing physical and chemical properties of the flours was investigated. The results provided appropriate technical information for selection of wheat varieties to produce high quality Korean salted noodles. Noodle quality was quantified based on measurement of the appearance and texture of noodles. When consumer preference tests were conducted, a firmer and more elastic texture was preferred for Korean white salted noodles, however, when appearance was included in the consumer tests, noodles made with Australian wheat were favored over Korean wheats. Korean flour was found to produce firmer and more elastic noodles, whereas Australian flour produced brighter, creamier colored noodles. In flour quality tests, Korean flours were found to have a higher setback viscosity and lower swelling power than Australian flour. Additionally, Korean flours had higher water absorption values. Protein content of flour was an important parameter affecting the firmness of Korean noodles, whereas setback viscosity and swelling power were the major determinants of elasticity. Overall, the important parameters for determination of the quality of Korean salted noodles were high setback viscosity, low swelling power, and high protein content.

Physicochemical Characteristics of Rice Flour Developed as Rice Powder and Quality Characteristics of Rice Cakes (쌀가루전용 품종들의 이화학적 특성 및 설기의 품질 특성)

  • Park, Ji Won;Choi, Sun Young;Chun, Areum;Jeong, Heon Sang;Lee, Youn Ri
    • The Korean Journal of Food And Nutrition
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    • v.32 no.4
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    • pp.395-400
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    • 2019
  • This study attempts to analyze the physicochemical characteristics of rice flour developed as rice powder for exclusive use, steamed rice cake recipes developed as basic recipefor rice cakes. The study also aims to compare the quality characteristics of steamed rice cakes in an effort to establish the possibilities of developing various rice cake recipes. The moisture content and amylose content increased as the rice powder particles for exclusive use became finer. With regards to water uptake, in the case of the Hungara type, the water uptake increased as rice powder particles increased in size. In the case of the Shingil and commercial types, the water uptake decreased as rice powder particles increased in size, and solubility and swelling force decreased as rice powder particles increased in size. In the case of chromaticity, Sulgidduk made with rice powder for exclusive use the brightness (L value) increased as powder particles became finer and the yellow indexes (b value) decreased, and this was especially pronounced in the Shingil type. The measurements of changes in the mechanical textures of Sulgidduk showed that rice types with larger particles led to lower hardness, cohesiveness, springiness, and chewiness.