• Korean Journal of Food Science and Technology
• /
• v.28 no.6
• /
• pp.1038-1044
• /
• 1996

The salt-fermented anchovy sauce (AS) was packed in round No. 307-1 can, and thermally processed at $121.1^{\circ}C$ to obtain Fo values of 3, 5 and 10. The changes of food components and qualifies by thermal processing of sterilized AS (RAS) were examined. The compositions of AS were as followed; pH 6.81, VBN 394.7 mg/100g, total nitrogen 2,195.5 mg%, amino-nitrogen 1,010.5 mg%, and acidity 10.5 ml. Viable cell counts of AS on 0%, 5%, 20% NaCl-medium were $2.9{\times}10^3,\;9.1{\times}10^3$ and not detected, respectively. And viable cell counts of RAS were not detected. Acidity, total nitrogen and amino nitrogen contents of AS decreased slightly with the severeness of heat treatments, whereas pH and VBN content were increased. Total free amino acid contents of raw AS and RAS were 12,802.5 mg% and $11,212.6{\sim}12,105.4\;mg%$, and major amino acids were alanine, glutamic acid, leucine, isoleucine, valine and lysine. Also contents of IMP, hypoxanthine, TMAO and TMA in AS and RAS were 42.1 mg% and $35.5{\sim}40.9\;mg%$, 103.7 mg% and $103.1{\sim}105.5\;mg%$, 78.8 mg% and $58.2{\sim}71.6\;mg%$, 55.8 mg% and $58.9{\sim}68.5\;mg%$ respectively. And a little changes were observed in whole volatile components of AS with severeness of heat treatments by GC chromatogram patterns. Judging from the chemical and sensory evaluations, the Fo 3 heat treatment sample was not inferior to raw AS, and maintained good quality for 1 year storage.

• Journal of the Mineralogical Society of Korea
• /
• v.22 no.4
• /
• pp.359-370
• /
• 2009

Arsenic and heavy metals leached out as a result of oxidation of tailings exposed to the surface pose a serious environmental contamination of mine areas. This study investigated how arsenic behavior is controlled by a variety of processes, such as oxidation of sulfides and formation or alteration of secondary minerals, based on mineralogical methods. The study was carried out using the tailing samples obtained from Nakdong mine located in Jeongseongun, Gangwondo. After separating magnetic and non-magnetic minerals using pretreated tailing samples, each mineral sample was classified according to their colors and metallic lusters observed by the stereoscopic microscope. Subsequently, the mineralogical properties were determined using various instrumental analyses, such as x-ray diffractometer (XRD), energy dispersive spectroscopy (EDS), and electron probe micro analyzer (EPMA). The literature review confirmed that various ore minerals were identified in the Nakdong ore deposits. In this study, however, there were observed a few original ore minerals as well as secondary and/or tertiary minerals newly formed as a result of weathering including oxidation. In particular, we did not recognize pyrrhotite which has been known to originally exist in a large abundance, but peculiarly colloform-type iron (oxy)hydroxides were identified, which indicates most of pyrrhotite has been altered by rapid weathering due to its large reactivity. In addition, a secondary scorodites filling the fissure of weathered primary arsenopyrites were identified, and it is speculated that arsenic is immobilized through such a alteration reaction. Also, we observed tertiary iron (oxy)hydroxides were formed as a result of re-alteration of secondary jarosites, and it suggests that the environment of tailing has been changed to high pH from low pH condition which was initiated and developed by oxidation reactions of diverse primary ore minerals. The environmental change is mainly attributed to interactions between secondary minerals and parental rocks around the mine. As a result, not only was the stability of secondary minerals declined, but tertiary minerals were newly formed. As such a process goes through, arsenic which was immobilized is likely to re-dissolve and disperse into surrounding environments.

• Journal of Korean Society of Environmental Engineers
• /
• v.38 no.6
• /
• pp.279-290
• /
• 2016

The performance of upflow anaerobic bioelectrochemical reactor (UABE), equipped with electrodes (anode and cathode) inside the upflow anaerobic reactor, was compared to that of upflow anaerobic sludge blanket (UASB) reactor for the treatment of acidic distillery wastewater. The UASB was stable in pH, alkalinity and VFAs until the organic loading rate (OLR) of 4.0 g COD/L.d, but it became unstable over 4.0 g COD/L.d. As a response to the abrupt doubling in OLR, the perturbation in the state variables for the UABE was smaller, compared to the UASB, and quickly recovered. The UABE stability was better than the UASB at higher OLR of 4.0-8.0 g COD/L.d, and the UABE showed better performance in specific methane production rate (2,076mL $CH_4/L.d$), methane content in biogas (66.8%), and COD removal efficiency (82.3%) at 8.0 g COD/L.d than the UASB. The maximum methane yield in UABE was about 407mL/g $COD_r$ at 4.0 g COD/L.d, which was considerably higher than about $282mL/g\;COD_r$ in UASB. The rate limiting step for the bioelectrochemical reaction in UABE was the oxidation of organic matter on the anode surface, and the electrode reactions were considerably affected by the pH at 8.0 g COD/L.d of high OLR. The maximum energy efficiency of UABE was 99.5%, at 4.0 g COD/L.d of OLR. The UABE can be an advanced high rate anaerobic process for the treatment of acidic distillery wastewater.

• Journal of Food Hygiene and Safety
• /
• v.34 no.4
• /
• pp.354-360
• /
• 2019

In order to extend the shelf life of Wasabi paste, the effects of citric acid were confirmed at $35^{\circ}C$ for 28 days. Citric acid-treated groups contained citric acid in amounts of 0.05, 0.10, 0.17, 0.30, and 0.40%, respectively. Quality characteristics of Wasabi pastes were determined in pH, titratable acidity, soluble solid content, color values, microbial analysis (aerobic bacteria, yeast), gas production, and content of allyl isothiocyanate. The pH and titratable acidities of Wasabi pastes added with citric acid were indicated as 4.03-5.19 and 4.23-4.82%, respectively. Soluble solid content was significantly different according to concentrations of citric acid. L values showed the highest at $50.05{\pm}0.46$. a and b values were increased during the storage period. Total aerobic bacteria and yeast counts of Wasabi pastes were decreased in a dose-dependent manner. Gas production from Wasabi pastes showed at 19.55-19.80 mL/tube after 28 days of storage. The addition of citric acid (0.3% or more) to the Wasabi paste resulted in increased storage stability.

• Journal of Environmental Science International
• /
• v.19 no.8
• /
• pp.951-960
• /
• 2010

Sediment works as a resource for electric cells. This paper was designed in order to verify how sediment cells work with anodic material such as metal and carbon fiber. As known quite well, sediment under sea, rivers or streams provides a furbished environment for generating electrons via some electron transfer mechanism within specific microbial population or corrosive oxidation on the metal surfaces in the presence of oxygen or water molecules. We experimented with one type of sediment cell using different anodic material so as to attain prolonged, maximum electric power. Iron, Zinc, aluminum, copper, zinc/copper, and graphite felt were tested for anodes. Also, combined type of anodes-metal embedded in the graphite fiber matrix-was experimented for better performances. The results show that the combined type of anodes exhibited sustainable electricity production for ca. 600 h with max. $0.57\;W/m^2$ Al/Graphite. Meanwhile, graphite-only electrodes produced max. $0.11\;W/m^2$ along with quite stationary electric output, and for a zinc electrode, in which the electricity generated was not stable with time, therefore resulting in relatively sharp drop in that after 100 h or so, the maximum power density was $0.64\;W/m^2$. It was observed that the corrosive reaction rates in the metal electrodes might be varied, so that strength and stability in the electric performances(voltage and current density) could be affected by them. In addition to that, COD(chemical oxygen demand) of the sediment of the cell system was reduced by 17.5~36.7% in 600 h, which implied that the organic matter in the sediment would be partially converted into non-COD substances, that is, would suggest a way for decontamination of the aged, anaerobic sediment as well. The pH reduction for all electrodes could be a sign of organic acid production due to complicated chemical changes in the sediment.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1998.02a
• /
• pp.120-120
• /
• 1998

Boron nitride (BN) films have attracted a growing interest for a variety of t technological applications due to their excellent characteristics, namely hardness, c chemical inertness, and dielectrical behavior, etc. There are two crystalline phases 1551; of BN that are analogous to phases of carbon. Hexagonal boron nitride (h-BN) has a a layered s$\sigma$ucture which is spz-bonded structure similar to that of graphite, and is t the stable ordered phase at ambient conditions. Cubic boron nitride (c-BN) has a z zinc blende structure with sp3-bonding like as diamond, 따ld is the metastable phase a at ambient conditions. Among of their prototypes, especially 삼Ie c-BN is an i interesting material because it has almost the same hardness and thermal c conductivity as di없nond. C Conventionally, significant progress has been made in the experimental t techniques for synthesizing BN films using various of the physical vapor deposition 밍ld chemical vapor deposition. But, the major disadvantage of c-BN films is that t they are much more difficult to synthesize than h-BN films due to its narrow s stability phase region, high compression stress, and problem of nitrogen source c control. Recent studies of the metalorganic chemical vapor deposition (MOCVD) of I III - V compound have established that a molecular level understanding of the d deposition process is mandatory in controlling the selectivity parameters. This led t to the concept of using a single source organometallic precursor, having the c constituent elements in stoichiometric ratio, for MOCVD growth of 삼Ie required b binary compound. I In this study, therefore, we have been carried out the growth of h-BN thin f films on silicon substrates using a single source precursors. Polycrystalline h-BN t thin films were deposited on silicon in the temperature range of $\alpha$)() - 900 $^{\circ}$C from t the organometallic precursors of Boron-Triethylamine complex, (CZHs)3N:BRJ, and T Tris(dimethylamino)Borane, [CH3}zNhB, by supersonic molecular jet and remote p plasma assisted MOCVD. Hydrogen was used as carrier gas, and additional nitrogen w was supplied by either aDlIDonia through a nozzle, or nitrogen via a remote plasma. T The as-grown films were characterized by Fourier transform infrared spectroscopy, x x-ray pthotoelectron spectroscopy, Auger electron spectroscopy, x-ray diffraction, t transmission electron diffraction, optical transmission, and atomic force microscopy.roscopy.

• Asian-Australasian Journal of Animal Sciences
• /
• v.22 no.6
• /
• pp.836-842
• /
• 2009

The objectives of this study were to evaluate potential benefits of intercropping of corn with runner bean for a smallsized farming system, based on land equivalent ratio (LER) and silage yield and quality of corn intercropped with runner bean (Phaseolus vulgaris L.), in arid conditions of Turkey under an irrigation system. This experiment was established as a split-plot design in a randomized complete block, with three replications and carried out over two (consecutive) years in 2006 and 2007. Seven different mixtures (runner bean, B and silage corn sole crop, C, 10% B+90% C, 20% B+80% C, 30% B+70% C, 40% B+60%C, and 50% B+50%C) of silage corn-runner bean were intercropped. All of the mixtures were grown under irrigation. The corn-runner bean fields were planted in the second week of May and harvested in the first week of September in both years. Green beans were harvested three times each year and green bean yields were recorded each time. After the 3rd harvest of green bean, residues of bean and corn together were randomly harvested from a 1 $m^{2}$ area by hand using a clipper when the bean started to dry and corn was at the dough stage. Green mass yields of each plot were recorded. Silages were prepared from each plot (triplicate) in 1 L mini-silos. After 60 d ensiling, subsamples were taken from this material for determination of dry matter (DM), pH, organic acids, chemical composition, and in vitro DM digestibility of silages. The LER index was also calculated to evaluate intercrop efficiencies with respect to sole crops. Average pH, acetic, propionic and butyric acid concentrations were similar but lactic acid and ammonia-N levels were significantly different (p<0.05) among different mixtures of bean intercropped with corn. Ammonia-N levels linearly increased from 0.90% to 2.218 as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio. While average CP content increased linearly from 6.47 to 12.45%, and average NDF and ADF contents decreased linearly from 56.17 to 44.88 and from 34.92 to 33.51%, respectively, (p<0.05) as the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, but DM and OM contents did not differ among different mixtures of bean intercropped with corn (p>0.05). In vitro OM digestibility values differed significantly among bean-corn mixture silages (p<0.05). Fresh bean, herbage DM, IVOMD, ME yields, and LER index were significantly influenced by percentage of bean in the mixtures (p<0.01). As the percentage of bean increased in the mixtures up to a 50:50 seeding ratio, yields of fresh bean (from 0 to 24,380 kg/ha) and CP (from 1,258.0 to 1,563.0 kg/ha) and LER values (from 1.0 to 1.775) linearly increased, but yields of herbage DM (from 19,670 to 12,550 kg/ha), IVOMD (from 12,790 to 8,020 kg/ha) and ME (46,230 to 29,000 Mcal/ha) yields decreased (p<0.05). In conclusion, all of the bean-corn mixtures provided a good silage and better CP concentrations. Even though forage yields decreased, the LER index linearly increased as the percentage of bean increased in the mixture up to a 50:50 seeding ratio, which indicates a greater utilization of land. Therefore, a 50:50 seeding ratio seemed to be best for optimal utilization of land in this study and to provide greater financial stability for labor-intensive, small farmers.

• Food Science of Animal Resources
• /
• v.30 no.3
• /
• pp.472-478
• /
• 2010

The effects of rosemary and $\alpha$-tocopherol, added individually or in combination, on broiler performance, thiobarbituric acid reactive substance (TBARS), total plate count (TPC) and meat color of chicken thigh meat were investigated. Three hundred broiler chicks divided into five groups were fed a basal diet (control) or basal diet supplemented with 5 g rosemary/kg (T1), 10 g rosemary/kg (T2), 200 mg $\alpha$-tocopherol/kg (T3), or 5 g rosemary/kg + 200 mg $\alpha$-tocopherol/kg (T4) for 5 weeks. Following slaughter, chicken meat was stored at $4^{\circ}C$ for 10 days. All treatments did not influence the performance. Rosemary supplementation delayed lipid oxidation in thigh meat during refrigerated storage. T2 was significantly (p<0.05) more effective in delayed lipid oxidation compared to T1, but was inferior to T3. Samples containing a combination of antioxidant had lower TBARS values than those containing the individual antioxidants, indicating a synergistic effect. TPC was significantly increased (p<0.05) in thigh meat of all groups throughout the refrigerated storage. The T3 and control groups showed TPC counts that did not differ from each other during the entire storage period. However, rosemary supplementation was associated with bacterial counts that were significantly lower (p<0.05) than the control and $\alpha$-tocopherol groups at day 3 of storage and thereafter. For this period, T1 presented TPC counts that were significantly higher than the T2 group (p<0.05). At all storage times, the thigh meat of rosemary-fed chickens was redder than control (higher $a^*$), while no differences in $L^*$ and $b^*$ values were found. A synergistic effect was obtained from the combination of rosemary with $\alpha$-tocopherol, whereas individual use of the antioxidants significantly improved color stability compared to the control.

• Food Science and Preservation
• /
• v.19 no.3
• /
• pp.420-427
• /
• 2012

The objective of this research was to investigate the effect of immersion in Rhus verniciflua Stokes extract (RVSE) on the total reducing ability (TRA), protein oxidation and myoglobin oxidation of beef steak (Hanwoo longissimus muscle) stored with high oxygen-modified-atmosphere packaging (MAP) (HOMAP, 75% $O_2$+20% $CO_2$+5% $N_2$) and low oxygen-MAP (LOMAP, 0% $O_2$+20% $CO_2$+80% $N_2$) at $4^{\circ}C$ for nine days. RVSE induced TRA (p<0.05), metmyoglobin (MetMb) formation, and the CIE $H^{\circ}$ value but reduced the carbonyl content and R630-R580, as an index of the intensity of redness by oxymyoglobin, and the CIE $L^*$,$a^*$, and $C^*$ values. HOMAP maintained a lower TRA, MetMb concentration, and CIE $H^{\circ}$ value but had higher R630-R580 and CIE $L^*$, $a^*$, and $C^*$ values compared to LOMAP. Therefore, RVSE induced TRA and protein oxidation stability but reduced myoglobin stability in Hanwoo beef steak. In addition, the effects of HOMAP were opposite those of RVSE.

• Korean Journal of Food Science and Technology
• /
• v.49 no.1
• /
• pp.8-13
• /
• 2017

Octenyl succinylated (OSA) potato starch was dextrinized by two methods: ultrasound (at 25, 50, or $70^{\circ}C$ for 1 h; OSA-25UT, OSA-50UT, and OSA-70UT, respectively) and acid hydrolysis (for 1 or 4 h; OSA-AD1H or OSA-AD4H, respectively), and the properties of the resulting starch were analyzed. The melting enthalpy of OSA-70UT decreased the most (from 14.0 to 10.0 mJ/mg), indicating chain degradation. For pasting properties, as ultrasound treatment temperature increased, peak viscosity decreased (2884, 2550, and 1888 cP, respectively), whereas acid hydrolysis increased peak viscosity and decreased pasting temperature. The relative crystallinity of OSA-dextrin produced by ultrasound or acid hydrolysis significantly decreased (from 33.61 to 14.90-26.03 and 19.28-20.05, respectively) as temperature or time increased, yet a B-type crystal pattern was maintained. Regarding emulsifying stability and sensory tests of mayonnaise prepared with OSA potato dextrin, mayonnaise with OSA-70UT was stable for short storage period (1 week), however mayonnaise with OSA-AD1H was the most suitable for long storage periods (from 2 to 4 weeks). In addition, the OSA-70UT was the most acceptable for mayonnaise in the sensory test.