• Title/Summary/Keyword: physical and chemical effects

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Effects of the Heat-Treatment on the Nutritional Quality of Milk - I. Historical Development of the Heat-Treatment Technology in Milk - (우유의 열처리가 우유품질과 영양가에 미치는 영향 - I. 우유 열처리 기술의 발달사 -)

  • Jung, Anna;Oh, Sejong
    • Journal of Dairy Science and Biotechnology
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    • v.34 no.4
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    • pp.271-278
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    • 2016
  • The main purpose of milk heat-treatment is to improve milk safety for consumer by destroying foodborne pathogens. Secondly, heat-treatment of milk is to increase maintaining milk quality by inactivating spoilage microorganisms and enzymes. Pasteurization is defined by the International Dairy Federation (IDF, 1986) as a process applied with the aim of avoiding public health hazards arising from pathogens associated with milk, by heat treatment which is consistent with minimal chemical, physical and organoleptic changes in the product. Milk pasteurization were adjusted to $63{\sim}65^{\circ}C$ for 30 minutes (Low temperature long time, LTLT) or $72{\sim}75^{\circ}C$ for 15 seconds (High temperature short time, HTST) to inactivate the pathogens such as Mycobacterium bovis, the organism responsible for tuberculosis. Ultra-high temperature processing (UHT) sterilizes food by heating it above $135^{\circ}C$ ($275^{\circ}F$) - the temperature required to destroy the all microorganisms and spores in milk - for few seconds. The first LTLT system (batch pasteurization) was introduced in Germany in 1895 and in the USA in 1907. Then, HTST continuous processes were developed between 1920 and 1927. UHT milk was first developed in the 1960s and became generally available for consumption in the 1970s. At present, UHT is most commonly used in milk production.

Metabolomic approach for discrimination of processed ginseng genus (Panax ginseng and Panax quinquefolius) using UPLC-QTOF MS

  • Park, Hee-Won;In, Gyo;Kim, Jeong-Han;Cho, Byung-Goo;Han, Gyeong-Ho;Chang, Il-Moo
    • Journal of Ginseng Research
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    • v.38 no.1
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    • pp.59-65
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    • 2014
  • Discriminating between two herbal medicines (Panax ginseng and Panax quinquefolius), with similar chemical and physical properties but different therapeutic effects, is a very serious and difficult problem. Differentiation between two processed ginseng genera is even more difficult because the characteristics of their appearance are very similar. An ultraperformance liquid chromatography-quadrupole time-of-flight mass spectrometry (UPLC-QTOF MS)-based metabolomic technique was applied for the metabolite profiling of 40 processed P. ginseng and processed P. quinquefolius. Currently known biomarkers such as ginsenoside Rf and F11 have been used for the analysis using the UPLC-photodiode array detector. However, this method was not able to fully discriminate between the two processed ginseng genera. Thus, an optimized UPLC-QTOF-based metabolic profiling method was adapted for the analysis and evaluation of two processed ginseng genera. As a result, all known biomarkers were identified by the proposed metabolomics, and additional potential biomarkers were extracted from the huge amounts of global analysis data. Therefore, it is expected that such metabolomics techniques would be widely applied to the ginseng research field.

Amorphous Ultrafine Particle Preparation for Improvement of Bioabailability of Insolube Drugs: Effect of Co-Grinding of UDCA with SLS (난용성 의약품의 생체이용률 증진을 위한 무정형 초미립자의 조제 : UDCA와 SLS의 혼합분쇄 효과)

  • 정한영;곽성신;김현일;최우식
    • YAKHAK HOEJI
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    • v.46 no.2
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    • pp.102-107
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    • 2002
  • The particle size of medicinal materials is an important physical property which affects the pharmaceutical behaviors such as dissolution, chemical stability, compressibility and bioavailability of solid dosage forms. The size reduction of raw pharmaceutical powder is needed to formulize insoluble drugs or slightly soluble drugs and to improve the pharmaceutical properties such as the solubility, the pharmaceutical mixing and the dispersion. The objective of the present study is to evaluate the grinding characteristics of ursodeoxycholic acid(UDCA) as a model of insoluble drugs. The effects of the grinding time and the amount of additive on particle size distribution of ground UDCA were investigated. Grinding of insoluble drug, UDCA and a series of dry co-grinding experiments of UDCA with sodium lauryl sulfate(SLS) as an additive were carried out using a planetary ball mill. It was measured that the median diameter and the particle size distribution of ground products with grinding UDCA and additive SLS by Mastersizer. As a result of co-grinding of UDCA and SLS, the particle size of co-grinding products was decreased more than single grinding one. However, it was observed that co-grinding products were reaggregated to larger particles after 120 min.

Effects of Coupling and Dispersion Agents on the Properties of Styrene-Butadiene Rubber/Butadiene Rubber Compounds Reinforced with Different Silica Contents

  • Yang, Jae-Kyoung;Park, Wonhyeong;Ryu, Changseok;Kim, Sun Jung;Kim, Doil;Kim, Jong-Ho;Seo, Gon
    • Elastomers and Composites
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    • v.53 no.3
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    • pp.109-123
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    • 2018
  • The effect of the silica content on the state and properties of silica-filled styrene-butadiene rubber/butadiene rubber (SBR/BR) compounds containing coupling and dispersion agents was evaluated by varying the content of silica from 50 to 120 phr. Bis-[(triethoxysilyl)propyl] tetrasulfide (TESPT) and zinc 2-ethylhexanoate (ZEH) were used as the coupling and dispersion agents, respectively. The maximum silica content in the pristine material was 80 phr, which increased to 120 phr upon the addition of TESPT and ZEH. The incorporation of TESPT considerably improved most of the rubber properties due to its coupling action and the suppression of silica flocculation, while further addition of ZEH resulted in additional improvements. The properties of the rubber compounds with different silica contents can be fully explained either by an enhancement of the rubber-silica interactions or by their deterioration due to an excessive amount of silica aggregates.

Characterization of $HfO_2 /SiON$ stack structure for gate dielectrics (ALD를 이용한 극박막 $HfO_2 /SiON$ stack structure의 특성 평가)

  • Kim, Youngsoon;Lee, Taeho;Jaemin Oh;Jinho Ahn;Jaehak Jung
    • Proceedings of the International Microelectronics And Packaging Society Conference
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    • 2002.11a
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    • pp.115-121
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    • 2002
  • In this research we have investigated the characteristics of ultra thin $HfO_2 /SiON$stack structure films using several analytical techniques. SiON layer was thermally grown on standard SCI cleaned silicon wafer at $825^{\circ}C$ for 12sec under $N_2$O ambient. $HfO_2 /SiON$$_4$/$H_2O$ as precursors and $N_2$as a carrier/purge gas. Solid HfCl$_4$was volatilized in a canister kept at $200^{\circ}C$ and carried into the reaction chamber with pure $N_2$carrier gas. $H_2O$ canister was kept at $12^{\circ}C$ and carrier gas was not used. The films were grown on 8-inch (100) p-type Silicon wafer at the $300^{\circ}C$ temperature after standard SCI cleaning, Spectroscopic ellipsometer and TEM were used to investigate the initial growth mechanism, microstructure and thickness. The electrical properties of the film were measured and compared with the physical/chemical properties. The effects of heat treatment was discussed.

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Integrity Test of DCM Treated Soils with a Cross-hole Sonic Logging (시추공간 음파검층법을 이용한 심층혼합 개량지반의 건전도 조사)

  • 김진후;조성경
    • Journal of Ocean Engineering and Technology
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    • v.15 no.1
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    • pp.73-78
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    • 2001
  • Soundness evaluation of a structure being constructed under the sea is usually difficult. In this study, a cross-hole sonic logging(CSL) which have been used for non-destructive test of concrete piles is adopted for the integrity test and monitoring of DCM(deep cement mixing) treated soils. Chemical and physical characteristics of raw ground materials are analysed to delineate ground environmental effects on the strength of DCM treated soils. In order to convert cross-hole sonic logging data into compressive strength, correlations between compressive strengths and wave velocities of core samples have been obtained. It is found that there is little effect of ground environment on the strength of the DCM treated soils, and the density distribution of core samples and cross-hole logging data show that a defective zone may exist in the DCM treated soils. With the time lapse, however, the defective zone has been cured and consequently, compressive strength of the DCM treated soils increases and satisfies the design parameter. From this study it can be concluded that the cross-hole sonic logging can be used for the integrity test as well as monitoring the curing stage of the structures, successfully.

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Determination of Leaching Requirements in the Unripened Tidal Reclaimed Paddy Fields (간척초기답의 제염용수량 결정을 위한 기초연구)

  • 손재권
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.42 no.2
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    • pp.55-62
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    • 2000
  • In order to make the reasonable irrigation plan in the unripended tidal reclaimed paddy fields, the estimation of irrigation water requirements by soil textures and water management methods for the normal growth of crops is very important . This study was carried out to determine leaching requirements before cultivating crops. For the purpose of this study, the physical and chemical properties of soil samples used in the desalinization experiments were analyzed, and change of salinity by supplying water and leaching water were investigated in the experimental field with lysimeters. As a result considering the soil textures, desalinization effects of good drainage soils(S1) were better than those of poor drainage soils (S2). In the changes of salinity of the soils with supplying water by water management methods, among the good grainage soils with culvert treatment(S1CW), salinity of S1CW3 with 1, 120mm and S1W4 with 1, 440mm supplying water were 2.6dS/m and 1.1dS/m respectively, and salinity of S1NW4 with 1.680mm among those non-culvert treatment (S1NW) was 3.0dS/m, less than critical salanity value 3.0dS/m. On the other hand, of the poor drainage soils with cultvert treatment , salinity of S2CW3 was ranged 9.4-6.0dS/m with supplied water, and that of non-culverted treatment S2NW as 12.3-8.4dS/m.

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Effects of Rice-green Manure Crop Cropping Systems on Soil Characteristics and Rice Yield in Paddy Field

  • Cho, Hyeoun-Suk;Jeon, Weon-Teai;Seong, Ki-Yeung;Kim, Chung-Guk;Jeong, Kwang-Ho;Park, Woo-Yeong
    • Korean Journal of Organic Agriculture
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    • v.19 no.spc
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    • pp.153-156
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    • 2011
  • Supplying rate of nitrogen at HV was 172.8 kg $ha^{-1}$, HV/B was 64.3 kg $ha^{-1}$ and B was 38.6 kg $ha^{-1}$. The Rice yield was 7.05 ton $ha^{-1}$ when the nitrogen supply was the largest with HV and 5.42 ton $ha^{-1}$ was produced on HV/B. The chemical characteristics of soil have lower pH and exchangeable cations(Ca and Mg) at B, HV and HV/B, rather than at CF because green manure was applied at the former step. However, the physical characteristics of the soil and the porosity showed different tendency which was that it was better at the green manure crops than CF. Nitrogen nutrient balance was showed the most balanced at CF and field of application of green manure crops were required the appropriate management if future crops would be cultivated because nitrogen nutrient could be exhausted or accumulated.

A Study on Effects of Oil Contaminated Soil on the Growth of Plant (유류오염토양이 식물식생에 미치는 영향에 관한 연구)

  • Choi, Min-Zoo;Kim, Joo-Young;Kim, Jung-Hoon;Choi, Sang-Il
    • Journal of Soil and Groundwater Environment
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    • v.15 no.1
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    • pp.50-56
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    • 2010
  • Oil contamination soil has been one of the most environmental social issues for decades in the inside and outside of country. The law of soil environmental preservation was carried out in the 1990s and the government controlled not only soil environment management and the remediation of contaminated soil but also promoted the development of remedial technology and cleanup business of contaminated soil by national policy. In addition to agriculture areas, the main oil contaminated sites are a gas station, oil reservoir, petro-chemical complex, site of railway carriage base and military camp. The contamination-frequency of agriculture area and effect sites are low but it has significantly important area on account of producing food for human beings. Therefore, we should be concerned about oil contamination damage of agriculture area. The oil contamination damage of agriculture area influenced drop of birth and breeding since the oil directly adheres to seeds and farm products even diffusion of contaminated soil to cultivation area. The studies of the crops and the food vegetation has not enough detailed data caused by the incident of oil contamination. This study investigated the effect of oil in germination and growth of selected plant seeds. In this study, we try to verify whether the oil contamination by accidents on farmland influenced the damage of farm produce and the mutual relation both oil contaminated soil or the vegetation of crops. The impact of oil on plant development was followed by phytotoxicity assessments. The plants exhibited visual symptoms of stress, growth reduction and perturbations in developmental parameters. The increase of the degree of pollution induced more marked effects in plants, likely because of the physical effects of oil. The relationships between the phytotoxicity contents of plants and growth reduction suggest a chemical toxicity of fuel oil. In addition, while cleaned up the contaminated soil under the standard of contaminated soil we examined it was suitable for region standard and it may have practical possibility for fill material of construction of afforestation and molding soil of landfill.

Effects of Polyurethane Coatings on 304 Stainless Steel Formed by Thermoset for Safety Management of Industrial Disaster (산업 재해의 안전관리를 위한 열경화에 의한 304 스테인레스 스틸에 대한 폴리우레탄 도료의 영향)

  • Kim, Ki-Jun;Lee, Joo-Youb
    • Journal of the Korean Applied Science and Technology
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    • v.29 no.2
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    • pp.317-322
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    • 2012
  • The microstructures were examined by SEM, FT-IR spectra, tensible properties mole % of [NCO/OH], and particle size analyzer. Growing concerns in the environment-friendly industries have led to the development of solvent-free formulations that can be cured. We had synthesized the polyurethane resin having the ability to protect stainless steel against corrosion. Compared with general packing materials and coatings, this resin is highly stronger in intensity and longer durability. Polyurethane resins were composed of polyols, IPDI, silicone surfactant, catalyst and crosslink agent. Moreover, thermal fillers such as $Al_2O_3$, fume silica and $ZrO_2$ not only accelerated the curing rate but also improved the physical property as thermal barriers. The rigid segments of polyurethane in mechanical properties were due to crosslink agent and the increase of [NCO/OH]. In conclusion, the polyurethane microstructure with crosslink agent can be good material for themoset coating of metal substrates such as stainless steel.