• Title/Summary/Keyword: Drying method

Search Result 1,448, Processing Time 0.037 seconds

Influence of Polycyclic Aromatic Hydrocarbons Formation in Sesame Oils with Different Roasting Conditions (참깨의 볶음 조건이 참기름 중 polycyclic aromatic hydrocarbons 생성에 미치는 영향)

  • Seo, Il-Won;Nam, He-Jung;Shin, Han-Seung
    • Korean Journal of Food Science and Technology
    • /
    • v.41 no.4
    • /
    • pp.355-361
    • /
    • 2009
  • Polycyclic aromatic hydrocarbons (PAHs) are environmental carcinogenic compounds that arise by several means including food processing methods such as smoking and direct drying and cooking. This study examined the concentration of PAHs in sesame oils with various roasting temperatures (190, 220 and $250^{\circ}C$), methods (direct heating vs. indirect hot air heating), and times (5, 10, 15, 20 and 25 min). The PAHs in the sesame oils were analyzed using liquid-liquid extraction and solid-phase clean up (Florisil), followed by HPLC with fluorescence detection. According to the results, mean levels of total PAHs increased when the sesame oils were roasted at increasing temperatures and times. The sesame oil roasted at $250^{\circ}C$ for 25 min had the highest mean value of total PAHs (4.66 ${\mu}g$/kg). The results of this study suggest that the indirect hot air roasting method decreased PAH formation during sesame oil processing.

Processing Conditions of Salted Anchovy 2. Changes of Taste Compounds during Processing of Salted Anchovy by Salting Methods (염장 멸치의 제조조건 2. 염장방법에 따른 염장 멸치의 가공 중 맛성분의 변화)

  • CHO Young-Je;SHIM Kil-Bo;JU Jung-Mi;KIM Tae-Jin;YOOK Ji-Hee;CHO Min-Sung
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.36 no.1
    • /
    • pp.18-23
    • /
    • 2003
  • We investigated the changes of free amino acid, ATP related compounds and sensory evaluation during ripening of dry or brine salted-anchovy. The total free amino acid content of the salted-anchovy ripened at $20^{\circ}C$ was higher than that of the salted-anchovy ripened at $5^{\circ}C.$ The IMP content of raw anchovy was higher than that of any other ATP related compound and decreased rapidly during ripening, resulting in increased hypoxanthin (Hx). The sensory evaluation results indicated 5 and 4 months for dry and brine salted-anchovy, respectively, as the minimum time required to obtain an adequate ripened salted-anchovy. We concluded that processing condition of ripened salted-anchovy was to ripened for 5 months at $5^{\circ}C$ by drying salting method.

Study on Recovery of Au from Flotation Tailing of Gold (금(金) 浮選(부선) 광미(鑛尾)로부터 금(金)의 회수(回收)에 관한 연구(硏究))

  • Shin, Seung-Han;Kang, Hyun-Ho;Hong, Jong-Won;Lee, Jin-Soo;Park, Je-Hyun;Han, Oh-Hyung
    • Resources Recycling
    • /
    • v.19 no.6
    • /
    • pp.61-69
    • /
    • 2010
  • S.M.C (DSME), only operating gold mine in Korea, is processing about 160 ton/day to recover gold and more than 150 ton/day of tailing is produced. Some portion of the tailings are used as a filler material after drying, but most of them are stored on the tailing dam. As a result of chemical analysis by a fire assay method, it contained Au 1.5~2.0 g/ton and 225~300 g per day of gold is getting discarded. It is urgent to develop a technology to recover and reutilize Au. In the present study, flotation tests were carried out to recovery gold for the tailings. Test results show that products with gold grade 21.31 g/ton(Au grade) and 62.73% (Au recovery) were obtained under the optimal conditions including KAX addition rate 97.2 g/ton, frother AF 65 (0.248 l/ton) and depressant sodium silicate (4 kg/ton), it's possible to recover one of the most valuable metal Au, by re-feeding to rougher flotation.

A Study on the Development of Non-PC High-Early-Strength Concrete Without Steam Curing (증기양생이 불필요한 PC부재용 조강형 콘크리트 개발에 관한 연구)

  • Jun, Woo-Chul;Lee, Ji-Hwan;Park, Hee-Gon;Lee, Jae-Sam;Kim, Kyung-Min;Cho, In-Sung
    • Journal of the Korea Institute of Building Construction
    • /
    • v.14 no.2
    • /
    • pp.156-162
    • /
    • 2014
  • This study aims to develop a rapidly hardening type of concrete to achieve the removal of form intensity (more than 10MPa) using the method of curing at room temperature in order to solve some economic environmental problems by omitting the steam curing process involved in producing PC (Precast Concrete). Therefore, this study evaluated a rapidly hardening cement containing a high amunt of C3S, which is very responsive in expressing early intensity, and a rapidly hardening type of concrete which uses some hardening accelerator to increase thehydration reaction of $C_3S$. The results of the experiment on concrete using some hardening accelerator are asfollows. In the slump flow experiment for identifying the liquidity and the air test, the desired values were met. The compression strength showed rapid expression response by 12 hours, and met the desired value within 6~9 hours. Its drying shrinkage value and Autogenous shrinkage value were measured as below ($-754.5{\times}10^{-6}$),and satisfied the requirements. In addition, in the Semi-Adiabatic Temperature Test, it was found that the concrete rose to its peak temperature within 24 hours and then its temperature dropped.

CuO Nanograss as a Substrate for Surface Enhanced Raman Spectroscopy

  • Lee, Jun-Young;Park, Jiyun;Kim, Jeong-Hyun;Yeo, Jong-Souk
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2013.08a
    • /
    • pp.249-249
    • /
    • 2013
  • Surface-enhanced Raman spectroscopy (SERS) is a sensitive approach to detect and to identify a variety of molecules. To enhance the Raman signal, optimization of the gap between nanostructures is quite important. One-dimensional materials such as nanowires, nanotubes, and nanograsses have great potential to be used in SERS due to their unique sizes and shape dependent characteristics. In this study we investigate a simple way to fabricate SERS substrates based on randomly grown copper oxide (CuO) nanowires. CuO nanograss is fabricated on pre-cleaned Cu foils. Cu oxidized in an ammonium ambient solution of 2.5 M NaOH and 0.1 M $(NH_4)_2S_2O_8$ at $4^{\circ}C$ for 10, 30, and 60 minutes. Then, Cu(OH)2 nanostructures are formed and dried at $180^{\circ}C$ for 2 h. With the drying process, the Cu(OH)2 nanostructure is transformed to CuO nanograss by dehydration reaction. CuO nanograss are grown randomly on Cu foil with the average length of 10 ${\mu}m$ and the average diameter of a 100 nm. CuO nanograsses are covered by Ag with various thicknesses from 10 to 30 nm using a thermal evaporator. Then, we immerse uncoated and Ag coated CuO nanowire samples of various oxidation times in a 0.001M methanol-based 4-mercaptopyridine (4-Mpy) in order to evaluate SERS enhancement. Raman shift and SERS enhancement are measured using a Raman spectrometer (Horiba, LabRAM ARAMIS Spectrometer) with the laser wavelength of 532 nm. Raman scattering is believed to be enhanced by the interaction between CuO nanograss and Ag island film. The gaps between Ag covered CuO nanograsses are diverse from <10 nm at the bottom to ~200 nm at the top of nanograsses. SERS signal are improved where the gaps are minimized to near 10s of nanometers. There are many spots that provide sufficiently narrow gap between the structures on randomly grown CuO nanograss surface. Then we may find optimal enhancement of Raman signal using the mapping data of average results. Fabrication of CuO nanograss based on a solution method is relatively simple and fast so this result can potentially provide a path toward cost effective fabrication of SERS substrate for sensing applications.

  • PDF

Screening of Antioxidant Activity in Dansam(Salvia miltiorrhiza) and Additional Effect on the Shelf-Life and the Characteristics of Yakgwa (단삼추출물의 항산화능 검색 및 약과에의 첨가효과)

  • 김윤화;한영실;백재은;송태희
    • Korean journal of food and cookery science
    • /
    • v.19 no.4
    • /
    • pp.463-469
    • /
    • 2003
  • This study was carried out to investigate the antioxidant activities of Dansam (S. miltiorrhiza). The Dansam (S. miltiorrhiza) was extracted with ethanol and methanol, and the extracts were fractionated with hexane, chloroform, ethyl acetate and butanol and water, in that order. The antioxidant activities of Dansam (S. miltiorrhiza) were determined by measuring the radical scavenging effects, using the 1, l-diphenyl-2-picryl-hydrazyl (DPPH) method. The electron donating ability was shown to be about 50% (IC50) at concentration of L-ascorbic acid, Dansam that reflected eliminatory effect by 50% were 9.48$\mu\textrm{g}$/$m\ell$, 8.28$\mu\textrm{g}$/$m\ell$, and l2.59$\mu\textrm{g}$/$m\ell$ respectively. According to the results of the above anti oxidation experiments, those for the group with the added Dansam showed a decreased oxidation, but the antioxidation increased with time. With a storage temperature of 60 C for 5 days, the acid value for the relative antioxidant activities were higher than in the Control group. The peroxide values for the relative antioxidant activities were also higher than in the Control group. The TBA values for the relative antioxidant activities were higher than in the Control group.

Quality Characteristics of Loaf Bread Added with Takju Powder (탁주 분말을 첨가한 식빵의 품질 특성)

  • Jeong, Jin-Woong;Park, Kee-Jai
    • Korean Journal of Food Science and Technology
    • /
    • v.38 no.1
    • /
    • pp.52-58
    • /
    • 2006
  • Characteristics of dough added with up to 4.0% takju powder and resultant bread were studied. Doughs added with takju power spray-dried after fermentation with starter (SDWS) and takju power spray-dried after fermentation without starter (SDOS) showed higher pH decreases than those added with takju power freeze-dried after fermentation with starter (FDWS) and takju power freeze-dried after fermentation without starter (FDOS) even after 1st fermentation. After 1st fermentation, volume of dough added with 1-4% SDWS was high, with 1% SDWS showing highest value of 23.6 mL. Volume of bread added with SDOS showed highest value. At 1-2% SDWS and SDOS addition, doughs showed highest specific volume values, which decreased at higher than 3% addition, while specific volume increased with increasing FDWS and FDOW contents. L values of SDOS- and FDOS-added doughs decreased gradually with increasing SDOS and FDOS contents compared to SDWS and FDWS addition. In loaf bread added with takju powder less than 2%, loaf bread added with spray-dried takju powder had higher appearance, color, texture, taste, and overall acceptability values compared to those added with freeze-dried takju. Although not significantly, loaf bread added with 1% SDWS showed slightly higher values in appearance, color, yeastiness, texture, taste, and overall acceptability, and showed higher flour odor acceptability than non-added loaf bread. These results indicate addition of takju powder improves flavor of bread.

Study of Dried Korean Native Plants Using for Floral Clusters (건조 자생식물 종별 꽃다발 이용 가능성 검토)

  • Sohn, Kwanhwa;Kwon, Hye Jin
    • FLOWER RESEARCH JOURNAL
    • /
    • v.16 no.4
    • /
    • pp.266-274
    • /
    • 2008
  • Korean native plants were investigated for their suitability to be used for floral clusters after drying. Floral clusters which were made in semi-sphere with a hand-tied method and can be fit in $22{\times}22{\times}37cm$ paper boxes were made with 37 species. Among 37 species, the 14 species which were easy to dry, to make floral clusters, and have not been used in other countries, were Echinochloa crus-galli var. frumentacea, Imperata cylindrica var. koenigii, Muhlenbergia huegelii, Phleum pratense, Setaria glauca, and Setaria viridis in Gramineae, Artemisia capillaris, Artemisia montana, and Chrysanthemum indicum in Compositae, Agastache rugosa, Elsholtzia ciliata, Elsholtzia splendens in Labiatae, Carex neurocarpa in Cyperaceae, and Vitex rotundifolia in Verbenaceae were used with leaves, flowers, and fruits. The suitable plants for a floral cluster in $22{\times}22{\times}37cm$ paper box, a wreath in $22{\times}22{\times}6cm$ paper box, and a flower arrangement in $22{\times}22{\times}22cm$ paper box, which were made to a set, were 10 species, that is Phragmites communis, Setaria glauca, Setaria viridis, Artemisia capillaris, Artemisia montana, Chrysanthemum indicum, Elsholtzia ciliata, Elsholtzia splendens, Mosla punctulata, and Vitex rotundifolia.

Physicochemical quality characteristics of hot water extracts of processed ginseng based on different heat treatments (열처리 방법에 따른 가공 인삼 열수추출물의 이화학적 품질 특성)

  • Kang, Yoon-Han;Zhou, Rui;Kim, Hyo Jin;Kim, Ji Eun;Shin, Il Shik
    • Food Science and Preservation
    • /
    • v.25 no.1
    • /
    • pp.155-163
    • /
    • 2018
  • The present study was carried out to investigate the physicochemical properties of hot water extracts of red ginseng powder prepared by two-stage hot air drying method using steamed ginseng and steaming liquid for 2.5 h under high-temperature and high-pressure autoclave condition. The total polyphenols, total flavonoids, total sugar, acid polysaccharides and crude saponin in hot water extracts from red ginseng powder were analyzed and determined, and the flavor components of ginseng were measured using color difference meter and an electronic tongue. The total polyphenol, total flavonoid, total polysaccharide, and acid polysaccharide of the red ginseng hot water extract obtained by autoclaving (ARG) were 9.06 mg GAE/g, 3.38 mg NE/g, 35.22 g/100 g, and 10.90 g/100 g, respectively. The final contents of the total polyphenols, total flavonoids, crude saponin were higher than those determined using other red ginseng methods; the time required for steamed red ginseng production reduced. The total ginsenoside content of ginseng including Rb1 was 10.69 mg/g, which is the lowest ARG. The processing conditions affected the conversion to ginsenosides unique to red ginseng. Red ginseng and steaming liquid obtained from the autoclave are expected to be in need for non-food materials and products as well as foods by improving the flavor components through conversion of red ginseng components into low molecular weight.

Granulation of Fine Zeolite Powder by Adding Polyvinyl Alcohol (Polyvinyl Alcohol첨가(添加)에 의한 Zeolite미분(微粉)의 입상화(粒狀化))

  • Choi, Jyung;Choi, Choong Ryeol;Lee, Dong Hoon
    • Korean Journal of Soil Science and Fertilizer
    • /
    • v.28 no.2
    • /
    • pp.123-129
    • /
    • 1995
  • For the propose of increasing the value added, zeolite powder was granulated by adding Polyvinyl Alcohol (PVA) as cementing material. The optimal concentration of PVA for granulation and the physical properties of the prepared granule were investigated. Four percent PVA stock solution was made by adding distilled water at $90^{\circ}C$ water bath and incorporated with zeolite. The contents of water stable granule above 2.0mm in diameter was 98.0% in the case of 0.3% PVA addition and almost 100% in the case of 0.6% PVA addition. Increasing PVA concentration of granules increased the hardness and decreased the infiltration rate and the maximum water holding capacity of granules, However, the drying method hardly affected the physical properties of granules. With the increase in the mixing ratios of kaolinite or bentonite to zeolite, the hardness of granules increased but high water contents of granules resulted in rapid decrease in the hardness of granules. However, when smectite or perlite was mixed with zeolite, the increase in mixing ratios to zeolite resulted in the decrease in hardness, the increase in the infilteration rate and maximum water holding capacity of granules.

  • PDF