• 제목/요약/키워드: physicochemical index

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광주광역시 도심 하천의 이화학적 환경과 수생식물 분포 비교연구 (Comparison both Physicochemical Environment and Distribution of Hydrophytes in Rivers of Downtown Gwangju Metropolitan City)

  • 임동욱;유윤미;황인천
    • 환경생물
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    • 제23권2호
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    • pp.120-128
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    • 2005
  • 2003년 3월부터 10월까지 영산강 수계 중 광주시 권역에서 선택한 총 14개 조사지역에서 수질의 이화학적 환경과 수생식물의 분포를 분석하였다. 전체 수생식물은 35과 68속 85종 9변종으로 총 94분류군이 확인되었다. 수계별로 수질의 이화학적 환경에 따라 오염지역과 비 오염지역을 구분하고 수생식물 분포양상을 확인하였다. 그 결과 가장 오염이 심한 것으로 여겨지는 광주천의 하류인 유덕동 일대에서 오염된 곳에 주로 분포하는 흰 꽃여뀌와 소리쟁이 등이 우점하였으며, 침수식물과 부엽 식물은 전혀 확인되지 않았다. 황룡강 일대와 영산강 상부지역 일대는 비교적 수질이 양호하여 비오염지역으로 판단되며, 이 지역에서 생육하는 달뿌리풀, 고마리, 물억새 등이 분포하였다. 광주시를 통과하는 동안 생활하수가 많이 유입되는 광주천 하류는 수생식물이 생육하기 힘든 수질환경인 것으로 판단되므로. 수질환경 개선을 위한 노력이 절실히 필요 할 것으로 판단된다.

케이신 포스포펩티드/키토올리고당 나노 복합체 형성과 특성 연구 (Formation and Characterization of Casein Phosphopeptide/Chitosan Oligosaccharide NanoComplex)

  • 백윤서;하호경;이지홍;이미령;이원재
    • Journal of Dairy Science and Biotechnology
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    • 제36권3호
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    • pp.164-170
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    • 2018
  • 본 연구에서는 CPP와 CSO를 사용하여 약 187~282 nm 크기의 균일한 구형의 나노 복합체를 성공적으로 제조하였다. 나노 복합체는 제조 공정 요인인 CPP 농도와 pH 조절을 통해 입자 크기, 다분산 지수, 그리고 표면 전하와 같은 나노 복합체의 물리화학적 특성을 조절할 수 있음을 확인하였다. 또한 CPP/CSO 나노 복합체의 분말화 공정을 통해 분말화 된 나노 복합체의 식품 적용성을 증진시킬 수 있음을 알 수 있었으며, food-grade 물질인 CPP와 CSO를 사용하여 제조한 나노 복합체는 향후 잠재적인 칼슘 전달체로써 식품 산업에 이용될 수 있을 것으로 기대된다.

Comparative effects of dry-aging and wet-aging on physicochemical properties and digestibility of Hanwoo beef

  • Kim, Ji-Han;Kim, Tae-Kyung;Shin, Dong-Min;Kim, Hyun-Wook;Kim, Young-Boong;Choi, Yun-Sang
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권3호
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    • pp.501-505
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    • 2020
  • Objective: The purpose of this study was to investigate the effects of aging methods (AM) i.e. dry-aging (DA) and wet-aging (WA) on the physicochemical properties and in vitro digestibility of proteins in beef short loin. Methods: Short loins (M. longissmus lumborum), were trimmed and boned-out on the fifth day postmortem, from a total of 18 Hanwoo, which were purchased from a commercial slaughterhouse. Short loins were separated randomly grouped into one of the three treatments: control, WA (1℃, 7 days), and DA (1℃, 0.5 m/s, 85% relative humidity [RH], 30 days). Results: Dry-aged beef (DAB) exhibited higher pH, water holding capacity (WHC), myofibrillar fragmentation index (MFI), and digestibility, however lower lightness, redness, and yellowness values, cooking loss, and shear force (SF), than those of wet-aged beef (WAB) (p<0.05). The myosin light chain band intensity of DAB was higher than that of control and WAB in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The in vitro digestibility of aged beef was highly (p<0.001) correlated to physicochemical properties except WHC. The correlation coefficient between AMs and WHC was higher than that between AM and SF (p<0.05) or MFI (p<0.001). A high correlation was observed between SF and MFI (p<0.001). Conclusion: Thus, we believe that DAB is more advantageous than WAB owing to its high digestibility and WHC and low SF.

Physicochemical and Sensory Properties of Yogurt Supplemented with Corni fructus during Storage

  • Noh, Hyo Ju;Seo, Hye Min;Lee, Jun Ho;Chang, Yoon Hyuk
    • Preventive Nutrition and Food Science
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    • 제18권1호
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    • pp.45-49
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    • 2013
  • This study was carried out to determine a possibility of adding Corni fructus extract (CFE) into yogurt for improving the neutraceutical properties of yogurt and the effects of adding CFE (2~6%, v/v) on the physicochemical and sensory properties of the products during a 15-day storage period at $4^{\circ}C$. Incorporation of CFE into the yogurt samples resulted in a significant pH reduction and a significant increase in titratable acidity. When evaluating the color of the yogurt, the $L^*$-values were not significantly influenced by CFE supplementation; however, the $a^*$- and $b^*$-values significantly increased with the addition of CFE during storage. The power law and Casson models were applied to assess the flow behavior of CFE-added yogurt samples. The magnitudes of apparent viscosity (${\eta}_{a,100}$), consistency index (K), and yield stress (${\sigma}_{oc}$) for 4~6% CFE yogurt samples were significantly greater than those for the control, indicating that CFE can be used as a thickening agent for yogurt. The sensory test revealed that addition of CFE (2~4%) to yogurt did not significantly affect the overall scores, but the overall preference score for 6% CFE yogurt was significantly decreased. Based on the data obtained from the present study, we concluded that the concentrations (2~4%) of CFE could be used to produce a CFE-added yogurt without the significantly adverse effects on the physicochemical and sensory properties.

들께와 땅콩의 혼합 채유가 들기름의 이화학적 특성 및 산화안정성에 미치는 영향 (Effect of the Mixing Extraction of Perilla Seed and Peanut on Physicochemical Characteristics and Oxidative Stability of Perilla Oil)

  • 권용주;김충기;오현화
    • 한국식품영양과학회지
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    • 제28권6호
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    • pp.1212-1219
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    • 1999
  • The oils were extracted from the mixture of roasted(for 20 min at 190oC) perilla seeds(RPS) and roasted (commercially) peanuts(RPN) by solvent extraction(SE) and mechanical expression(ME). The effects of mixing ratio on physicochemical characteristics and oxidative stability of their oils were investigated. Yields of both SE and ME oils were increased as the RPN ratio in the mixture increased. In all the SE and ME oils, the major fatty acids were oleic, linoleic and linolenic acid, and total saturated fatty acids increased gradually, but total unsaturated fatty acids decreased gradually as the RPN ratio in the mixture was increased. The specific gravity and refractive index of both SE and ME oils decreased as the RPN ratio in the mixture was increased. Acid value, saponification value and iodine value of SE oils decreased as the RPN ratio in the mixture increased, whereas acid value and iodine value of ME oils decreased and saponification value increased. The colors of ME oils were darker brownish than SE oils. The oxidative stability of SE oils was decreased as the RPN ratio in the mixture increased, whereas that of ME oils was increased. Sensory evaluation of all the oils extracted from the mixture with various mixing ratio showed significant differences in flavor, taste, color and overall acceptance(p<0.01). The oil extracted from the mixture of the mixing ratio of 8:2(RPS:RPN) showed slightly higher preference regardless of extraction method.

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Comparison of Physicochemical Characteristics of Hot-boned Chicken Breast and Leg Muscles during Storage at 20℃

  • Yu, Long-Hao;Lee, Eui-Soo;Chen, Hong-Sheng;Jeong, Jong-Youn;Choi, Yun-Sang;Lim, Dong-Gyun;Kim, Cheon-Jei
    • 한국축산식품학회지
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    • 제31권5호
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    • pp.676-683
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    • 2011
  • The aim of this study was to compare the physicochemical changes of hot-boned chicken breast and leg muscles. Chicken breast and leg muscles from 56 broilers were excised within a 15 min post-mortem (PM) and stored at $20^{\circ}C$. Physicochemical traits were determined at 0.5, 6, 12, and 24 h PM. The ultimate pH of leg muscle was higher than that of breast muscle (p<0.05). The content of glycogen in the breast muscle was relatively higher than that in the leg muscle until 6 h PM (p<0.05). R-values showing rigor mortis of breast and leg muscles were completed after or before 6 h PM. Breast muscle had less cooking loss than leg muscle (p<0.05). Drip loss did not significantly differ between breast and leg muscles with the exception of that at 6 h PM. The sarcomere length of leg muscle was relatively longer than that of breast muscle (p<0.05). The MFI of leg muscle was significantly lower than that of breast muscle (p<0.05). The shear force of leg muscle was lower than that of breast muscle at 6 and 12 h PM (p<0.05); however, that of both muscles did not significantly differ at 24 h PM.

Preliminary pharmacognostical and phytochemical evaluation of Stachys tibetica Vatke

  • Kumar, Dinesh;Bhat, Zulfiqar Ali;Kumar, Vijender;Chashoo, Ishtaq Ahmad;Khan, Nisar Ahmad;Ara, Irfat;Shah, Mohammad Yassin
    • 셀메드
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    • 제2권1호
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    • pp.11.1-11.7
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    • 2012
  • Stachys tibetica Vatke (Lamiaceae) is an important medicinal plant in the folk medicine of Ladakh, India and Tibet for the treatment of various mental disorders. Infusion and decoction of the whole plant is used as a cup of tea for a severe fever, headaches and to relieve tension. The recent study is aimed to evaluate the preliminary pharmacognostical and phytochemical nature of Stachys tibetica Vatke. The whole plant material was subjected to successive soxhlet extraction with petroleum ether (40 - $60^{\circ}C$), chloroform, ethyl acetate, methanol and finally decocted with water to get the respective extracts. The fluorescence characteristics of the powdered materials were analysed under ultraviolet light and ordinary light. Different physicochemical parameters such as ash value, extractive value, foaming index, pH values, loss on drying and determination of foreign matter were carried out as per WHO guidelines. The total fat, flavonoid, saponin and volatile contents were also determined. Macroscopical studies revealed the authentication of the plant drug. Physicochemical parameters helped to standardize the plant material while preliminary qualitative chemical tests of different extracts showed the presence of Glycosides, Carbohydrates, Phytosterols/triterpenoids, Saponins, Fixed oils, Fats and phenols/tannins. Quantification of the total flavonoids and saponins and contents were determined as $54.66{\pm}0.58mg/g$ and $75.42{\pm}0.48mg/kg$ respectively, while the volatile and fat contents were 6.5% and 0.7% respectively. Results may lay the foundation for the standardization of the drug and discovery of new molecules from S. tibetica for the treatment of various diseases.

Effects of red glasswort as sodium chloride substitute on the physicochemical properties of pork loin ham

  • Jeong, Tae-Jun;Kim, Tae-Kyung;Kim, Hyun-Wook;Choi, Yun-Sang
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권4호
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    • pp.662-669
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    • 2020
  • Objective: This study was conducted to evaluate the effect of red glasswort (RG) (Salicornia herbacea L.) curing on the physicochemical, textural and sensory properties of cooked pork loin ham (M. longissimus thoracis et lumborum). Methods: All treatments were cured with different salt and RG powder levels. RG0 treatment was prepared with only 4% NaCl (w/w) as a control, and RG25, 3% NaCl:1% RG (w/w); RG50, 2% NaCl:2% RG (w/w); RG75, 1% NaCl:3% RG (w/w); RG100, 0% NaCl:4% RG (w/w) treatments were prepared sequentially. All samples were individually vacuum packaged in polyethylene bags and stored for 7 d at 3℃±1℃. Results: The results showed that as the rate of RG substitution increased, pH value, redness, myofibrillar protein solubility, and myofibrillar fragmentation index increased (p<0.05), but salt concentration and shear force decreased (p<0.05). However, there were no significant differences in cooking loss and moisture content. In terms of sensory evaluation, RG100 exhibited higher scores in tenderness and juiciness than RG0 (p<0.05). Conclusion: The partial substitution of NaCl by RG could improve the physicochemical properties, textural and sensory characteristics of cooked pork loin. Therefore, it is suggested that RG as a natural salt replacer could be an effective ingredient for developing low-sodium cured hams.

한국식 핫소스의 저장 중 이화학적 특성 변화 (Changes of Physicochemical Characteristics of Korean Type Hot Sauce during Storage)

  • 권동진;이성;김유진;유진영;정건섭
    • 한국식품과학회지
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    • 제30권3호
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    • pp.548-551
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    • 1998
  • 우리 기호에 적합한 한국식 핫소스의 저장기간 중 이화학적 특성 변화를 조사하였다. 제조된 핫소스의 pH는 3.29, 적정산도 3.88% (w/w), capsanthin은 0.13% (w/w) capsaicin은 2.68 mg%이었다. $20^{\circ}C$$30^{\circ}C$ 항온기에 50일간 저장하면서 이화학적 성분 변화를 조사한 결과 pH 및 적정산도의 변화는 볼 수 없었던 반면 capsanthin과 capsaicin은 저장기간 동안 약간씩 감소하고 있었다. 저장기간 동안 10일마다 시료를 채취하여 관능검사를 실시한 결과 저장 30일부터 기호도가 급격히 감소하고 특히 색의 감소율이 큰 편이었다. 이화학적 성분과 관능검사 평가항목과의 상관성을 분석한 결과 capsanthin과 색과의 상관성이 높은 것으로 나타나 capsanthin의 함량을 핫소스의 품질지표로 선정하였으며 capsanthin 함량의 감소율을 근거로 하여 핫소스의 상대적인 유통기간을 예측한 바 $20^{\circ}C$에서는 232.5일, $30^{\circ}C$에서는 178.0일이 각각 예측되었다.

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진공포장한 소등심육의 냉장저장중 이화학적, 관능적 특성의 변화 (Changes of Physicochemical and Sensory Characteristics in Vacuum-Packaged Beef Loin during Cold Storage Time)

  • 정인철;문윤희;홍대진;김미숙
    • 한국식품영양과학회지
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    • 제27권2호
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    • pp.214-219
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    • 1998
  • This study was carried out to investigate the changes of physicochemical and sensory characteristics according to cold storage period of the vacuum-time beef loin. The pH was decreased for 10 days, and then was increased gradually during storage time. The lactic acid content during the initial storage was 483mg/100g, after storage for 10 days it was increased significantly (p<0.05) to 625mg/100g, and then was decreased with storage time. Regarding of color difference, the L values were 41.0~42.5, but after storage for 40 days they were increased significantly(p<0.05) to 46.2, the a and b values wee 17.3~14.3 and 7.2~5.8, respectively, they were no significant differences depending n storage time. The shear force values showed 584 and 560g for 0 and 10 days, respectively but after storage for 20 days it was decreased significntly(p<0.05) to 299g. The myofibrillar protein extractability was no significant difference for 20 days, howener, it was increased remarkably at 30 days(p<0.05). The myofibrillar fragmentation index was increased significantly (p<0.05) on 20 and 40 days, and the Mg-ATPase activity of myofibrils was increasd to 30 days. The free amino acid was increased during storage periods. The composition of amino acid was composed of glutamic acid, alanine, valine and lysine, which were predominant amino acids as 45%. The total free amino acid was increased 182.18mg/100g to 40 days. The raw meat aroma showed no significant changes during storage time, but the tenderness was increased until 30 days(p<0.05). The color was superior from 20 to 30 days. The taste of cooked meat indicated significant changer to 30 days, but was significantly inferior(p<0.05) at 40 days, the aroma was superior until 30 days(p<0.05). The palatability was superior between 20 and 30 days.

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