• Title/Summary/Keyword: Physico-chemical

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Differences in Health-related Fatty Acids, Intramuscular Fat and the Physico-chemical Quality in Mutton as Affected by Season, Place of Purchase and Meat Portion

  • Rani, Zikhona T.;Nantapo, Carlos W.T.;Hugo, Arnold;Muchenje, Voster
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.11
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    • pp.1630-1637
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    • 2014
  • The objective of the study was to determine the quality and fatty acid profiles of mutton cuts purchased from rural and urban localities in South Africa. Five hundred and ten samples were collected in four seasons from both rural and urban shops and butcheries. Samples were immediately transported to the laboratory in cooler boxes with ice where the following physico-chemical characteristics of mutton were determined; meat pH, color ($L^*$, $a^*$, and $b^*$), cooking losses and Warner Braztler shear force and replicates stored at $-20^{\circ}C$ pending fatty acid analysis. Meat $L^*$ values were lowest ($24.7{\pm}0.49$) in winter and highest ($32.2{\pm}0.49$) in spring. The loin and sirloin cuts recorded the highest intramuscular fat whilst rib and leg cuts recorded the lowest intramuscular fat. In conclusion intramuscular fat, fatty acid profiles and physico-chemical quality of mutton were significantly affected by season and meat portion and not necessarily by the locality and class of shop.

Improvement on the Functional Properties of Gelatin Prepared from the Yellowfin Sole Skin by Precipitation with Ethanol (알코올처리에 의한 각시가자미껍질 젤라틴의 기능성 개선)

  • Kim, Jin-Soo;Lee, Eung-Ho
    • Korean Journal of Food Science and Technology
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    • v.26 no.6
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    • pp.683-689
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    • 1994
  • With a view to utilizing effectively fish skin wastes from marine manufactory, a gelatin solution extracted from yellowfin sole skin was fractionated by precipitation with ethanol, and then the functional and physico-chemical properties for the fractionated gelatin were determined. Ethanol was added up to 50% of ethanol content to a gelatin solution extracted from yellowfin sole skin, then the mixture was left to stand at $0^{\circ}C$ for 12 hours. Finally, the precipitates were dried by hot-air ($40^{\circ}C$). The gel strength and melting point of a 10% gel of gelatin prepared from yellowfin sole skin by precipitation with ethanol has 322.4g and $23.3^{\circ}C$, respectively. The physico-chemical properties of the ethanol treated fish skin gelatin were superior to those of fish skin gelatin prepared without ethanol treatment. Besides, the functional properties of the ethanol treated gelatin were lower in solubility and higher in water holding capacity, oil binding capacity, emulsifying activity, emulsifying stability, foam expansion and foam stability than those of pork skin gelatin sold on market as well as gelatin prepared without ethanol treatment. It may be concluded, from these results, that the fish skin gelatin prepared by precipitation with ethanol can be effectively utilized as a human food by improving the functional properties.

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The Water Quality Assessment based on Phytoplankton Community and Physico-chemical Factors of Oship-stream, Songchun-stream and Namdae-stream in Gyeongsangbukdo (경상북도 오십천, 송천천과 남대천의 환경요인과 식물플랑크톤 군집분석에 의한 수질평가)

  • Kim, Yong-Jin;Lee, Ok-Min
    • Journal of Korean Society on Water Environment
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    • v.29 no.3
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    • pp.428-437
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    • 2013
  • Physico-chemical water quality parameters and the phytoplankton communities from 12 sites in Oship-stream, Songchunstream, and Namdae-stream, located Gyeongsangbukdo Uljin-gun, Yeongdeok-gun, and Pyeonghae-eup respectively, were investigated from April 2009 to February 2010. Oship-stream, which is an open estuary, was easily affected by ocean current compared to that of Songchun-stream and Namdae-stream. OS3 and OS4 conductivity was higher with a season average of 3,397 ${\mu}s/cm$. The streams were mesotrophic to hypertrophic. Biological oxygen demand (BOD) was about 3mg/L, which was level 2 on the water quality ratings, but a concentration of 5mg/L in April 2009 indicated increased pollution due to drought. A total of 118, 117, and 124 phytoplankton taxa were found in Oship-stream, Songchun-stream, and Namdae-stream, respectively. The apparent dominant species in the polluted waters included Cryptomonas ovata, Fragilaria construens var. venter, Oscillatoria limnetica, O. limosa, and Phormidium tenue. All of Oship-stream, SC2 and SC4 of Songchun-stream, and ND3 of Namdae-stream were eutrophic as a result of standing crop analysis. BOD was highly correlated with chlorophyll-a content(r=0.52). Phosphorus concentration and proliferation of phytoplankton were thought to most affect BOD concentration in all three streams.

Physico-Chemical Properties of Soils at the Ground of Landscape Planting in Reclaimed Land from the Sea (임해매립지의 식재지반별 토양 물리·화학적 특성)

  • Kim, Do-Gyun
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.4 no.4
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    • pp.12-18
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    • 2001
  • This study was carried out to analyze physico-chemical properties of soils at the ground of landscape planting in reclaimed land from the sea on Kwangyang Bay, South Korea. Physico-chemical properties of soils at each planting grounds were tested by ANOVA and were significantly(P<0.01) different. The difference came from the soil properties of the covered soil, the disturbance applied to the soil with land use and the accumulation of organic matter after landscape planting. Soil hardness, pH, ECe, Na and K level were in a stable condition at high then low of ground height for landscape planting. Organic matter accumulation was greater at lower planting grounds then top and slope ground of big mounding. The planting grounds of favorable growth for landscape trees were determined as following order : the slope ground and the top ground of big mounding>the ground of medium mounding>the coved ground of improve soil>the lower ground of big mounding>the filled ground of improve soil.

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Environmental Distribution and Fate of Perfluorinated Compounds (PFCs) as Emerging POPs: Physico-Chemical Properties, Emission, Contamination Level, Inter-phase Distribution and Long-Range Transport (잠재적 POPs로서의 과불소화화합물의 환경 내 분포 및 거동: 물성, 환경 내 농도수준, 상 분배 및 장거리이동을 중심으로)

  • Kim, Seung-Kyu
    • Environmental Analysis Health and Toxicology
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    • v.23 no.3
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    • pp.143-164
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    • 2008
  • Concern about perfluorinated compounds (PFCs) is growing nationally as well as globally. PFCs could be considered emerging POPs due to their environmentally persistent, bioaccumulative, and potentially harmful properties. Moreover. perfluoroalkylates (PFAs) such as PFOS and PFOA are reported to experience long-range transport (LRT) to the Arctic in spite of their low volatility and strong solubility. The possible pathways contributing to LRT have been proposed but are still in debate in combination with unclear source definition and uncertain physico-chemical properties. The environmental fate of PFCs is more complicated because of the presence of precursors that are degraded to PFAs and are extremely different from their daughters, PFAs. in physico-chemical properties. To what extent and through what pathways are human and wildlife exposed is determined by the environmental fate and distribution of PFCs. To define uncertainties in fate and distribution thus is critical to prevent erroneous policy and/or determination related with exposure and risk reduction. This article aimed to review controversy and/or uncertain issues for the environmental fate and distribution of PFCs and to prospect research topics necessary to dissolve uncertainties.

Sensory Characteristics and Physico-Chemical Change of the Loin of Lamb by Four Cooking Methods (네 가지 조리 방법에 따른 양등심의 이화학적 및 관능적 특성 연구)

  • Seo, Min-Suk;Yoo, Seung-Seok
    • Journal of the East Asian Society of Dietary Life
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    • v.20 no.1
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    • pp.84-94
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    • 2010
  • Physico-chemical analysis and sensory test of loin of lamb were carried out by four different methods such as grilling, pan-frying, oven-roasting and boiling. The crude fat content was all the same at three cooking methods except boiling. The moisture content was not different among grilling, pan-frying and oven-roasting. Hunter's color L-value(lightness) was lowest at grilling method. However, the heating loss appeared greatly at grilling. The hardness of the lamb-loin after cooking showed big differences with the control except boiling treatment. Amino acids in fillet contained highly in the order of glutamic acid > aspartic acid > cystein. The grilling showed a good value not only color of a sensory test but also the appearance. The oven-roasting cooking gave the tenderness and juiciness. The oven-roasting method showed good sensation to overall taste. Therefore, the oven-roasting (at $150^{\circ}C$ for 9 minutes) was suggested as the superior method when the loin of lamb is cooked for reducing off-flavour.

The Effects of High Pressure and Various Binders on the Physico-chemical Properties of Restructured Pork Meat

  • Hong, Geun-Pyo;Park, Sung-Hee;Kim, Jee-Yeon;Min, Sang-Gi
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.10
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    • pp.1484-1489
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    • 2006
  • This study was carried out to investigate the effect of high pressure and the addition of non-meat proteins on the physico-chemical and binding properties of restructured pork. Pressurizations were carried out at up to 200 MPa and non-meat proteins used as a binder were isolated soy protein (ISP), sodium caseinate (SC), whey protein concentrate (WPC) and egg white powder (EWP). The pH values of all treatments were affected by the level of pressure. $L^*$-value of all treatments increased significantly (p<0.05), while both $a^*$-value and $b^*$-value of all treatments showed a significant decrease (p<0.05) with increasing pressure level. Binders could contribute only additive effects on both pH and color of the treatments. It was found that high pressure improved the water binding capacities and binding strength of the treatments. Binders also improved the binding strength of restructured pork. However, SC and WPC had no effect on water binding properties under high pressure. These results indicate that the application of high pressure had more significant effect on restructuring meat than binders.

Oxidative Stability of Sesame Blended Oils (참기름 혼합유의 산화안정성)

  • 맹영선;박혜경
    • Korean journal of food and cookery science
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    • v.5 no.2
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    • pp.51-62
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    • 1989
  • In the present study, an attempt was made to investigate the oxidative stability of the various sesasme blended oils. Sesame blended oils were perpared by mixing sesame oil with various vegetalbe oils (soybean oil, corn oil, ricebran oil, rapeseed oil, cottonseed oil, and perilla oil) in a ratio of 3:7 (w/w). Fatty acid composition and some of physico-chemical characteristics of the sesame blended oils and vegetable oils including sesame oil were determined before the oxidation experiments. The fatty acid compositions and the physico-chemical characteristics of the vegetable oils changed by blending the oils with sesame oil and the extent of change varied with the type of oil. Particularly, the iodine value of the vegetable oils decreased significantly by sesame oil blending. The sesame blended oils and the vegetable oils including sesame oil were oxidized at $45^{\circ}C$ for 25 days in a dark place, and at $35^{\circ}C$ for 12 days under the irradiation of incandescent electric lamp (40 W). During the oxidation, some physico-chemical characteristics of the oils were determined to evaluate the oxidative stability. Based on the changes of peroxide values, the oxidative stability of the vegetable oils was improved by sesame oil blending.

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Postmortem Changes in the Physico-Chemical Characteristics of Korean Native Chicken (저장기간에 따른 한국산 토종닭고기의 품질 특성)

  • 성삼경;권연주;김대곤
    • Korean Journal of Poultry Science
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    • v.25 no.2
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    • pp.55-64
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    • 1998
  • This study was carried out to investigate the postmortem changes in physico-chemical characteristics of chicken meat with different breeds. Thigh and breast meats from Korean Native Chicken(KNC, 15-wk old), Wangchoo(15-wk old), and broiler(7-wk old) were stored at 5 ˚C. Differences in postmortem pH changes were not recognized among breeds, and pH showed by the lowest value at the 1st day of postmortem in all breeds. Breast meat had tendency to drop pH faster than thigh meat. Heme pigment contents showed no differences among breeds. KNC showed the lowest cholesterol contents in all breeds, total collagen contents showed the lowest value at the 1st day of postmortem, and thereafter it was gradually increased. Heat soluble collagen contents was lowest in Wangchoo. Water soluble and salt soluble protein showed the lowest extractability at the 1st day of storage. Broiler showed the highest extractability of these proteins and Wangchoo showed the lowest. Water holding capacity(WHC) had increasing tendency whilst cooking loss had decreasing tendency by the ageing. WHC of breast and thigh meat showed the highest values in KNC and broiler, respectively. Myofibrillar fragmentation index (MFI) was significantly increased in all breeds by the ageing. Breast and thigh meat showed almost same MFI in KNC and broiler, and in KNC and Wangchoo, respectively. Hardness of breast meat showed decreasing tendency by the ageing.

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Changes in Physico-Chemical Properties of Salted Sea Mustard (Undaria Pinnatifida) by Gamma Irradiation (염장미역의 감마선 조사에 따른 이화확적 특성 변화)

  • 변명우;권중호;이수정;남상명;조한옥
    • Journal of Food Hygiene and Safety
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    • v.6 no.3
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    • pp.165-169
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    • 1991
  • The effect of gamma irradiation on physico-chemical properties of salted sea mustard (Undaria pinnatifida) was investigated. Chlorophyll and carotenoid pigment of salted sea mustard were partially decreased by irradiation. However there was no significant difference in the retention rate of pigment between control and 2 kGy-irradiated samples after six months of storage at around $10^{\circ}C$, ranging values of 74 to 77% in chlorophyll and 54 to 56% in carotenoid. Total organic acids and volatile acids associated with the organoleptic quality of sea mustard increased in the samples of lower salt concentrations and of higher storage temperatures. The softening of sample tissue by irradiation was shown to be correlated with the extraction properties of alginic acid.

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