• Title/Summary/Keyword: pickling

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Characteristics of Conversion Coating of AZ31 Magnesium Alloy Formed in Chromium-Free Cerium-Based Solution (크롬 프리 세륨 용액에 의한 AZ31 마그네슘 합금의 화성 피막에 대한 특성 평가)

  • Kim, Myung Hwan;Lee, Dong Uk;Kwag, Sam-Tag;Moon, Myung-Jun
    • Journal of the Korean institute of surface engineering
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    • v.49 no.1
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    • pp.62-68
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    • 2016
  • A chromium-free Ce-based conversion coating formed by immersion in a solution containing cerium chloride and nitric acid on AZ31 magnesium alloy has been studied. The effects of acid pickling on the morphology and the corrosion resistance of the cerium conversion coating were investigated. The corrosion resistance of the conversion coating prepared on AZ31 Mg alloy after organic acid pickling was better than that of inorganic acid pickling. The morphology of the conversion-coated layer was observed using optical microscope and SEM. Results show that the conversion coatings are relatively uniform and continuous, with thickness 1.0 to $1.1{\mu}m$. The main elements of the conversion coating of AZ31 Mg alloy are Mg, O, Al, Ce and Zn by EDS analysis. The electrochemical polarization results showed that the Ce-based conversion coating could reduce the corrosion activity of the AZ31 Mg alloy substrates in the presence of chloride ions.

Physicochemical and Sensory Characteristics of Pickled Hen Egg and Its Calcium Content and Antioxidative Activity

  • Jang, Aera;Nam, Ki-Chang;Liu, Xian-De;Lee, Moo-Ha;Kim, Dong-Ho;Jo, Cheor-Un
    • Food Science and Biotechnology
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    • v.17 no.5
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    • pp.996-1002
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    • 2008
  • Pickled hen egg dipped in brewed apple vinegar for 7 and 14 days was prepared and changes of weight, pH, viscosity, calcium content, antioxidative effect, and sensory characteristics were determined. During a pickling, the egg weight was increased from 62.03 g at day 0 to 91.13 and 94.93 g at day 7 and 14, respectively. The pH of the egg white and yolk, initially at pH 10.24 and 6.56, was decreased, while that of the pickling solution was increased by the pickling days. Viscosity of the pickled egg white was significantly decreased with the pickling days (p<0.05). Significant antioxidative effect was found from the pickled egg mixture (egg white:yolk=1:1). Calcium content of the egg white after 7 and 14 days of the pickling was 280-300 times higher than the fresh egg white and 1.9 times higher than fresh egg yolk. Addition of plain yogurt and honey improved the sensory quality of a pickled egg and was able to mask the unpleasant sour taste. Results suggest that, in addition to the use of pickled egg by itself, egg-based foods such as mayonnaise with enforced calcium content can be developed using a pickled egg.

ENZYME ACTIVITY AND ACIDITY IN VINEGAR PICKLING OF ANCHOVY (멸치 Vinegar 절임시의 산도와 효소 활성)

  • HA Bong-Suk
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.3 no.4
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    • pp.207-212
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    • 1970
  • The fellowing results are obtained by experiment on the variation of enzyme activity during pickling anchovy (Engraulis japenicus) in vinegar. 1) Protease activity increased during brine-salting. It decreased for a short time by tile addition of acetic acid and gradually changed at an invariable ratio during pickling. 2) Lipase activity decreased during brine salting but increased temporarily by the addition of vinegar, after this no fixed tendency could he observed during pickling whereas acid value abviously increased. 3) VBN (Volatile basic nitrogen) and NaCl content quickly increased during brine salting. During pickling VBN increased slowly while NaCl content scarcely varied. 4) The bacterial plate count decreased suddenly when the anchovy were placed in brine but it increased during brine salting and decreased again when anchovy were pickled and the number of count remained the same thereafter. 5) To maintain preservation effects, the acidity of the vinegar must be maintained more than $2\%$ in the muscle. 6) Based on this experimental condition, it transpires that 8 days of immersion In brine produces sufficient salt concentration in the muscles. From the results of VBN, acidity, amino nitrogen, lipase activity, and organoleptic tests, the quality of pickle was still preserved after 47 days and taste of the pickle seemed best on the thirty second day of the storage.

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A Study on the Manufacture of $\alpha$-Fe$_2$O (Major Material of Ferrite) by Waste Pickling Liquor of Steel (강철의 산세폐액으로부터 Ferrite의 주원료인 Fe$_3$O$_3$의 제조에 관한 연구)

  • 최석진
    • Journal of the Korean Ceramic Society
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    • v.13 no.1
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    • pp.25-29
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    • 1976
  • The properties vary with quality of ferric-oxide that is major material of ferrites. In this point of view, a manufacturing method of pure and homogeneous fine ferric oxide is very important. The characters of this study are as follows: 1) Ferric oxide was made from waste pickling liquor of steel. 2) The crude ferric-oxide that is made by roasting the pickling liquor was dissolved in 20% HCI solution and then produced ferric chloride is purified by ethyl ether extraction. 3) The methanol solution of purified ferric chloride was sprayed into the refractory tube with compressed air and propane gas and then ignited leading to the ferric-oxide powder. 4) The produced oxide powder was introduced to the scrubber type vessel throught cooling system in order to collect the powder. 5) Crystalline phase of the powder was identified by X-ray diffraction and particle size, crystalline shape of the powder were investigated by settling method and electron microscope and the effects of concentration of ferric chloride in methanol on grain size were discussed. Results were obtained as fellows: 1) Total impurity in the ferric oxide produced from waste pickling liquor was 3.7%. 2) The solubilityof crude ferric oxide that was made from waste pickling liquor in HCI solution increased with the HCI concentration and reached to saturation range at 15% HCI concentration. 3) Extraction of FeCl3 increased with HCI concentration which is solvent. 4) Alpha ferric oxide obtained was very fine crystalline particles, the mean crystalline grain increased with the concentration of ferric chloride, and mean grain size distributed from 3.5$\mu$(at 0.5mole/l) to 0.5$\mu$(at 0.05mole/l).

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Changes in Isoflavone and Some Characteristics of Chokong of Germinated Soybeans during Pickling in Vinegar (발아콩을 이용한 초콩의 제조 중 Isoflavone 및 특성 변화)

  • Eom, Kwon-Yong;Kim, Joo-Sook;Choi, Hee-Sook;Cha, Bo-Sook;Kim, Woo-Jung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.3
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    • pp.359-365
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    • 2006
  • Changes in isoflavone and oligosaccharides, and some physicochemical properties of Chokong, a pickled and dried soybeans, were investigated during pickling in brewed vinegar at $20^{\circ}C$. The used soybeans were 24 hr germinated soybeans, which was maximumly increased in isoflavone content during germination. The isoflavone contents were significantly increased by approx. 80% in both glycosides and aglycone type of isoflavone after 20 day of pickling at $20^{\circ}C$. The isoflavone values of germinated Chokong were significantly higher than those of ungerminated ones. Pickling the soybeans in vinegar resulted in a rapid initial decrease in oligosaccharides, Particularly in raffinose and stachyose. The pH and soluble solids contents in vinegar increased markedly and L values decreased during initial pickling of 24 hr.

Effect of Pretreatment Methods on Quality Changes in Mushrooms(Pleurotus eryngii) during Pickling with Fermented Soybean Paste (전처리방법에 따른 새송이 된장절임의 품질특성 변화)

  • 윤광섭;황성희;정헌식
    • Journal of the East Asian Society of Dietary Life
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    • v.14 no.3
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    • pp.251-256
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    • 2004
  • This study was conducted to find the optimum pretreatment method to improve the quality of Pleurotus eryngii pickled with the fermented soybean paste. Blanching(70 , 10min), salting(5%, 20 , 72hr) and drying(50 , 3hr) were used as pretreatment methods. The moisture loss of the mushrooms during pickling was accelerated more by salting and drying. Salinity increase was retarded by salting. Surface and internal browning of the mushrooms were suppressed by blanching. Hardness tended to increase sharply until 20 days of pickling and then slowly decreased. In the sensory evaluation, mushrooms pickled for 40 days were scored as the highest. Blanching was a superior treatment compared to the others in term of color, taste, flavor, texture and overall acceptability.

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A Study on Coating Adhesion of Hot Rolled Galvanized Iron Manufactured without pickling process (산세생략형 열연 용융아연도금강판의 특성)

  • 최진원;전선호
    • Journal of the Korean institute of surface engineering
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    • v.32 no.1
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    • pp.21-30
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    • 1999
  • Coating adherance behavior of low carbon steels, produced by POSCO, Korea, was studied in order to study the characteristics of hot rolled galvanized iron(HGI) manufactured without pickling line and the development of its process. Galvanizing experiments were carried out in zinc pot with 0.2wt% Al after hot rolled plates with scale were reduced at $550~750^{\circ}C$ in 10~30% hydrogen gas atmosphere during 60~400seconds. The reduced plates and coated products were examined by SST, XRD, SEM and EPMA on their surfaces and cross sections. Coating layer of HGI manufactured with pickling line was composed of retained scale, Fe-Zn-Al compound, Fe-Zn compound ($\delta_1\;and\;\zeta$ Phase) and pure zinc. It was superior to HGI in coating adhesion. It seems to be due to forming of Fe-Zn-Al compound in interface of matrix and retained porous scale.

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Development of a High Power Ultrasonic Transducer for Steel Pickling Process

  • Han, Chang-Soo;Kim, Jeong-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 2001.10a
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    • pp.65.3-65
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    • 2001
  • In order to apply for pickling line in cold rolling process, a high power magnetostrictive ultrasonic transducer was developed. The transducer is expected to overcome the shortcomings of conventional high power ultrasonic transducers. The transducer consists of Fe-Co-V alloy sheets for the magnetostrictive material, an ultrasonic horn made of Hastelloy to withstand acid solution, and electric driving circuit. In the development, the transducer was designed with the theoretical and numerical methods such as finite element method, and was characterized with experimental water tanks. The developed transducers turned out to be able to generate the sound pressure up to 20,000 Pa, and to be suitable for application ...

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Physical, Chemical Properties and Structural Changes of Zaodan Pickled by Vacuum Decompression Technology

  • Sun, Naxin;Liu, Huiping;Zhang, Xiaowei;Wang, Hongni;Liu, Shaojuan;Chen, Pei;Yu, Weijie;Liu, Kai
    • Food Science of Animal Resources
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    • v.38 no.2
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    • pp.291-301
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    • 2018
  • To shorten the production cycle of Zaodan, this study first pickled Zaodan by a novel technology - vacuum decompression technology. Vacuum decompression technology could reduce the pickling time of Zaodan from 20 wk to about 9 wk. The protein content, moisture and pH of the Zaodan egg white gradually decreased with a concomitant increase in salt during the pickling process. The total sulfhydryl group (SH) group content of the egg white proteins was increased to $2.43{\times}10^{-3}mol/L$ after being pickled for 30 d, whereas the content of disulphide bonds (SS) was reduced to $23.35{\times}10^{-3}mol/L$. The surface hydrophobicity was lowest after pickling for 30 d. In addition, great changes occurred in the secondary structure of the egg white proteins after pickling for 20 d. The disappearance of ovomucin was noticeable based on sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis.

Application of SBR Process to Treat Pickling Wastewater including the High Nitrate and Ca+2 (고농도 질산성질소와 Ca+2을 함유한 산세폐수의 효과적인 처리를 위한 SBR 공정의 적용)

  • Kim, Seung-jun;Choi, Yong-su;Bae, Woo-keun
    • Journal of Korean Society on Water Environment
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    • v.22 no.2
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    • pp.215-221
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    • 2006
  • This research presents results from laboratory and pilot-scale experiments to remove high-nitrate in pickling wastewater using the sequencing batch reactor (SBR) as a biological method. During the experimental periods, the influent concentrations of NOx-N and $Ca^{+2}$ were analyzed to be 350-1,600 and 700-800 mg/L, respectively. In order to provide carbon source for denitrification, methanol has been added in proportion to the influent nitrate loading. The mean concentrations of MLSS and MLVSS, the fraction of volatile solids in sludge and the sludge volume index were measured to be 27 g/L, 5 g/L, 18.5% and 7.5, respectively. The solid retention time was kept in the range of 18 to 22 days, specific denitrification rate ($U_{dn}$) was $0.301g{NO_3}^--N/gVSS/day$. The oxidized nitrogen concentration of effluent ranged 2-34 mg/L with an average of 5.2 mg/L, the overall reduction in total nitrogen was more than 99.2%. In order to treat the pickling wastewater including the high concentration of nitrate and $Ca^{+2}$, the continuous flow process is not suitable because the specific gravity of the sludge is considerably increased by $Ca^{+2}$, thus the SBR process is shown to be very effective to treat the pickling wastewater.