• Korean Journal of Food Science and Technology
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• v.48 no.4
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• pp.335-340
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• 2016

This study was conducted to find out the most suitable DNA isolation methods for PCR detection of foodborne pathogens. Four DNA isolation methods including Universal Genomic DNA Extraction Kit (TaKaRa), PrepMan Ultra (Applied Biosystems), boiling method and alkaline lysis method (w/PEG) were tested and compared. The Universal Genomic DNA Extraction kit (TaKaRa) was considered as the more efficient isolation method for Escherichia coli O157:H7 and Staphylococcus aureus in lettuce, fish and beef. Meanwhile to detect the foodborne pathogens directly from foods without enrichment, the four different buffers such as double-distilled water, saline, glycine-saline, glycine-saline with Tween-20 and beef extract were also evaluated. As a result, saline was more suitable buffer for E. coli O157:H7. And double-distilled water was more suitable buffer than saline for S. aureus, respectively

• Child Health Nursing Research
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• v.10 no.1
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• pp.108-116
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• 2004

Purpose: There has been a number of reports on elution of bisphenol-A, an endocrine disrupting chemical, from milk bottles, all concerning the potential health effect of the substance. In this study, we measured the elution of bisphenol-A from milk bottles during boiling-water sterilization, to suggest a safe sterilization method. Method: Through the survey of 200 mothers, 78.5％ of them expressed their concern on the possible harmful effect of bisphenol-A, which might be eluted from the bottles. And it was found that most mothers use boiling-water to sterilize bottles; duration of boiling bottles could be divided into three groups of 3, 5, and 10 minutes. We measured the elution of bisphenol- A from three different brands of bottles, subject to various mode of sterilization found in the survey. Result: In all the measurements, the concentration of the eluted bisphenol-A was in the range of 0.3 - 0.7 ppb, far below 2.5ppm, the level set up by Korea Food ％amp; Drug Administration(KFDA) for a potential harmful effect. Conclusion: Although trace amount of bisphenol -A can be eluted from polycarbonate milk bottles during sterilization, and bottle feeding, the amount is found to be too small to cause any health related impact for infants.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.309-316
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• 2013

Quality changes of cooked meat products are dependent upon cooking temperature and heating methods. Pork ham is the most preferred pork dish using pork hams in South Korea although it is not suited to various cooking methods because its low fat content does not provide desirable physiochemical and sensory properties to consumers. Therefore, the objective of this study was to evaluate the effect of four different cooking methods on pork legs by comparing Ocoo, Sous-vide, steaming, and boiling technique at $80^{\circ}C$ and $100^{\circ}C$. Ultimately, the most effective cooking method and temperature to improve the quality of cooked pork hams was investigated. As the results of texture analysis, the samples cooked using Ocoo and Sous-vide methods showed higher springiness and cohesiveness than those using steaming and boiling methods. For the sensory evaluation, participants liked the hardness, juiciness, chewiness, tenderness of the samples using the OC method, resulting in the highest overall acceptance rate. The results of this study showed that using Ocoo or Sous-Vide cooking methods can improve the quality of cooked pork hams in both physicochemical and sensory properties.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.3
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• pp.425-436
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• 1987

Accurate predictions of heat transfer coefficient of vertical laminar film-boiling are very important in many engineering applications. There are many predictions, however they are not exact as yet, since they have used the assumption of constant thermodynamic properties in the analysis. In this paper, heat transfer of vertical film boiling was analysized by Runnge Kutta method using veriable thermodynamic properties. 1/4 interval method was exployed for the prediction of unknown wall boundary condition. Numerical computations were performed with varying the wall temperature and the free stream velocity of liquid. Results show that assumption of constant thermodynamic properties induced considerable error in predicting the heat transfer coefficient, friction factor, film thickness, and critical length for transition to turbulent flow. Comparision of the predicted heat transfer coefficient of present analysis with that from Bromley's correlation shows that the use of general latent heat in Bromely equation instead of modified latent heat is more desireable since it makes the coefficient of Bromley equation into constant.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.5 s.143
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• pp.472-478
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• 2005

From a rapid cooling to a slow cooling in the actual cooling process in shipyards, the phase of steel becomes martensite, bainite, ferrite, and pearlite. In order to simulate the cooling process, heat transfer analysis was performed considering the effects of impinging water jet, film boiling, and radiation. From above simulation it is possible to find the cooling speed at the inherent strain region and volume percentage of all phases in that region. By the suggested method based on the precise material properties calculated from volume percentage of all phases, it will be possible to predict the plate deformations by line heating more precisely. It is verified by comparing with some experimental results that the present method is very effective and efficient.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.10
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• pp.942-951
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• 2004

This paper presents the results of a theoretical study of the effect of radiation during free convective laminar film boiling for methanol/water binary mixtures on an isothermal vertical wall at atmospheric pressure. With the well-known boundary layer theory as a basis, a theoretical model has been formulated into consideration for mass diffusion at liquid phase. The equations are numerically solved by a similarity method to investigate the effects of radiation emissivity on the surface with various parameters such as wall superheat and composition of more volatile component at liquid phase far from the wall. From the results, the distributions of the physical quantifies are investigated in both phases. New correlations are proposed to predict the heat transfer coefficient of binary mixtures. It is shown that the proposed correlations are in good agreement with numerical results and with Bromley's correlation within maximum $11\%$ errors. It is also found that as the wall superheat is increased, radiation effect becomes more important.

• Asian-Australasian Journal of Animal Sciences
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• v.31 no.2
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• pp.293-300
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• 2018

Objective: This study observed the effects of cooking method and final core temperature on cooking loss, lipid oxidation, aroma volatiles, nucleotide-related compounds and aroma volatiles of Hanwoo brisket (deep pectoralis). Methods: Deep pectoralis muscles (8.65% of crude fat) were obtained from three Hanwoo steer carcasses with $1^+$ quality grade. Samples were either oven-roasted at $180^{\circ}C$ (dry heat) or cooked in boiling water (moist heat) to final core temperature of $70^{\circ}C$ (medium) or $77^{\circ}C$ (well-done). Results: Boiling method reduced more fat but retained more moisture than did the oven roasting method (p<0.001), thus no significant differences were found on cooking loss. However, samples lost more weight as final core temperature increased (p<0.01). Further, total saturated fatty acid increased (p = 0.02) while total monounsaturated fatty acid decreased (p = 0.03) as final core temperature increased. Regardless the method used for cooking, malondialdehyde (p<0.01) and free iron contents (p<0.001) were observed higher in samples cooked to $77^{\circ}C$. Oven roasting retained more inosinic acid, inosine and hypoxanthine in samples than did the boiling method (p<0.001), of which the concentration decreased as final core temperature increased except for hypoxanthine. Samples cooked to $77^{\circ}C$ using oven roasting method released more intense aroma than did the others and the aroma pattern was discriminated based on the intensity. Most of aldehydes and pyrazines were more abundant in oven-roasted samples than in boiled samples. Among identified volatiles, hexanal had the highest area unit in both boiled and oven-roasted samples, of which the abundance increased as the final core temperature increased. Conclusion: The boiling method extracted inosinic acid and rendered fat from beef brisket, whereas oven roasting intensified aroma derived from aldehydes and pyrazines and prevented the extreme loss of inosinic acid.

• Nuclear Engineering and Technology
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• v.39 no.6
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• pp.731-736
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• 2007

Radioactive organic wastes containing acetone, alcohol, and particularly tributyl phosphate (TBP)/dodecane contaminated with uranium are extracted from the PUREX process and the decontamination of related equipment. An evaporation method that utilizes existing DU oxidation apparatuses and ventilation systems and a typical muffle furnace installed with an aspirating system are adopted. A separation method using phosphoric acid especially for the TBP/dodecane waste is also studied and evaluated. The results show that a simple evaporation process is utilizable for wastes containing acetone or alcohol with a lower boiling point. A modified muffle furnace is more appropriate to dispose directly of organic wastes having a higher boiling point, such as TBP/dodecane, without generating a condensed waste solution. It is recommended that, when the uranium concentration of TBP/dodecane waste is much higher than stipulated levels, separation technology should be applied to remove uranium from the mixture. Each type of solvent after separation can then be considered disposable below the regulatory limit in the modified furnace discussed in this study.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.35 no.10
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• pp.1089-1095
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• 2011

Numerical simulation is performed for nucleate boiling on a micro-finned surface, which has been widely used to enhance heat transfer, by solving the equations governing the conservation of mass, momentum, and energy in the liquid and vapor phases. The bubble motion is determined by a sharp-interface level-set method, which is modified to include the effect of phase change and to treat the no-slip and contact-angle conditions, as well as the evaporative heat flux from the liquid microlayer on immersed solid surfaces such as micro fins and cavities. The numerical results for bubble formation, growth, and departure on a microstructured surface including fins and cavities show that the bubble behavior during nucleate boiling is significantly influenced by the fin-cavity arrangement and the fin-fin spacing.

• Journal of Sensor Science and Technology
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• v.22 no.6
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• pp.404-409
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• 2013

We devised calibration procedure for industrial thermometers by a comparison method at the boiling point of nitrogen (${\sim}-196^{\circ}C$). The uncertainty of the calibration was 4 mK (k = 2). As experimentally demonstrated in this work, the effect of the atmospheric pressure on the boiling point of nitrogen can be easily detected by the thermometer. Therefore, when the boiling point of nitrogen is used for calibration of thermometer by comparison, either a reference thermometer must be used to provide the reference temperature or the effect of atmospheric pressure should be carefully considered. The use of a copper block with a large thermal mass soaked into the liquid nitrogen was proven to be more reliable, and the stability of the temperature immersed into the copper block was 1.4 mK. The temperatures at the thermometer wells, evaluated by the crossed-measurement method to compensate for the inaccuracy of the thermometers and the linear drift of the temperature of the copper block, were equivalent within 0.23 mK of standard uncertainty.