• Journal of the KSME
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• v.56 no.10
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• pp.49-52
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• 2016

이 글에서는 터빈 Casing Bolt 분해조립 시 신기술 가열분해 공법을 적용하여, 정비기간 단축 및 Bolt 파손을 방지한 사례에 대해 소개하고자 한다.

• Journal of Food Hygiene and Safety
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• v.6 no.2
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• pp.83-87
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• 1991

Beef, pork and chicken on the market were analyzed for determination of tetracyclines residue and decomposition of tetracyclines by heating were studied. The content of oxytetracycline was trace in chicken A, 0.09 mg/kg in C and trace in beef C, pork A and B, but in the other samples was not detected oxytetracycline. Chlortetracycline residue was 0.14, 0.02 and 0.01 mg/kg in chicken A, C and beef B respectively. In HPLC analysis, two peaks of 8.1 and 9.0 min of retention time were found from beef and pork and expected to be component of meat, and because of same retention time, the one of 9.0 min interrupted determination of tetracycline. But those were not found in chicken, therefore the residue was 0.01 mg/kg in sample A. The residue were degradated rapidly by heating of roast, but slightly by that of boiling.

• Korean Journal of Food Science and Technology
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• v.23 no.3
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• pp.355-359
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• 1991

Effects of temperature and pH on thermal degradation of monosodium glutamate(MSG) were investigated during heating of 2% MSG solution at $100{\sim}200^{\circ}C\;and\;pH\;4{\sim}9$. The results showed that the degradation of MSG was very significantly affected by heating temperature and pH. Three hours of heating at $pH\;4\;and\;120^{\circ}C$ resulted appr. 73% MSG degradation while 3 hours at $100^{\circ}C$ decreased only 12%. The comparison study of initial rate of MSG degradation and degradation rate constants showed the highest degradation rate and rate constant and low values in the range of $pH\;6{\sim}8{\sim}$. The values of activation energy calculated from linear relationship of rate constants and 1/T were 18.3 and 9.2 kcal/mole for pH 4 and 5, respectively.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.226-230
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• 2005

본 연구는 고혈압을 억제하는 ACE inhibitory peptide가 한우에 함유되어 있는지를 조사하기 위한 기초연구로 한우의 우둔과 등심으로부터 Myosin B를 추출하여 가열한 것과 가열하지 않은 것으로 구분하여 pepsin으로 0, 1, 3, 6시간 동안 $37^{\circ}C$에서 가수분해 시켰다. 가수분해물을 전기영동을 실시하여 pepsin 처리시간에 따른 단백질의 변화를 검토하였고, ACE 저해 활성을 측정하였다. 전기영동의 결과 가열한 것은 가열하지 않은 것에 비해서 단백질의 변성과 소멸이 많이 일어나 밴드의 수가 적었다. Pepsin으로 가수분해한 시간이 길어짐에 일부 단백질이 소실되었고, 저분자의 단백질이 생성되었다. Pepsin으로 가수분해함에 따라 등심과 우둔에서 25, 32, 40 및 44 kDa는 소실되었고, 37 kDa의 분자량을 갖는 밴드는 생성되었으며, 27 kDa의 단백질은 처음상태 그대로 유지되었다. 가수분해물을 이용하여 ACE 저해활성도를 측정한 결과, 등심은 1시간 가수분해시 유의차가 있었으나, 우둔은 가열여부에 따라 유의차가 발견되지 않았다. 반면 등심과 우둔 모두 가수분해 시간이 증가하면 ACE 저해율은 상승하는 경향을 보였다. 이와 같은 결과를 토대로 한우로부터 추출한 Myosin B의 ACE 억제활성이 우수한 단백질분획을 찾아 아미노산 염기서열을 밝히고 고혈압 억제제로 합성 개발하는 연구를 차후 추진할 예정이다.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.120-124
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• 2007

The thermal degradation kinetics of alpha-, gamma- and delta-tocopherols was studied during heating at 100, 150 200 and 250$^{\circ}C$ for 5, 15, 30 and 60 min in the absence of oxygen. The tocopherols were separated by HPLC using a reversed phase ${\mu}$-Bondapak C$_{18}$-column with two kinds of elution solvent system in a gradient mode. The kinetics for degradation of ${\alpha}$-, ${\gamma}$- and ${\delta}$-tocopherols was analyzed as a function of temperatures and times. The degradation of tocopherols was described by the first-order kinetics in the absence of oxygen. The rate of tocopherols degradation was dependent on heating temperatures. The degradation rate constants for ${\alpha}$-, ${\gamma}$ and ${\delta}$-tocopherols showed an increasing trend as the heating temperature increased. The magnitude order of the experimental activation energy was ${\delta}$->${\gamma}$->${\alpha}$-tocopherol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.8
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• pp.1102-1105
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• 2006

The effect of heat treatments on in vitro starch hydrolysis of proso millet, sorghum, Job's tears, and buckwheat by pancreatic ${\alpha}-amylase$ was investigated. Grain samples were tested raw, boiled in water, or steamed/roasted. Starch content of the grains varied from 59.5% in Job's tears to 65.5% in proso millet, and amylose content varied from 5.3% in Job's tears to 36.3% in buckwheat. The in vitro starch hydrolysis of raw and heat-treated grains continuously increased during 60 min of hydrolysis. The starch hydrolysis (%) of raw grains after 60 min incubation was in the order of buckwheat (5.7%), proso millet (33.0%), Job's tears (51.2%), and sorghum (57.6%). Grains treated with steaming/roasting appeared to have higher starch hydrolysis rates than those with boiling except proso millet. Hydrolysis rates of buckwheat with a high amylose content appeared to be lower, compared to proso millet, sorghum, and Job's tears containing low amylose contents.

• Journal of Energy Engineering
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• v.24 no.1
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• pp.137-148
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• 2015

So far, the phenomenon of "electrification" has been deepened in Korean industry and especially direct heating energy which accounted for 44.0%(2010) of total energy consumed in Korean manufacturing has been significantly electrified. This paper decomposed electricity consumption for direct heating in Korean manufacturing from 1992 to 2012 using LMDI(Log Mean Divisia Index). This paper includes 4 different factors such as electricity proportion effect, direct heating proportion effect, energy intensity effect and added value effect. And this paper compared the consumption pattern by business type. As results, electricity proportion effect had contributed the most to the increase of electricity consumption for direct heating in Korean manufacturing. And Petrol-Chemical and Iron & Steel had the most electrification of direct heating.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.905-910
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• 2004

This study was carried out to observe the change of oriental melon juice quality during manufacture by heating condition and enzyme treatment. To use over-production oriental melon effectively, oriental melon juice was prepared with change of heating temperature and heating time. The heating conditions for minimum filtration time were 98.57$^{\circ}C$ and 11.29 min. The optimum conditions Predicted for separation ratio of clear solution, filtration time and browning color intensity of oriental melon juice were 98$^{\circ}C$, 13 min. In the pectin-degrading enzyme treatment test, turbidity showed minimum value in 4.40 mg％(pectin-degrading enzyme content)， 39.72 mg％ (gelatin content) and 24.09 min (treatment time)．Browning color intensity showed minimum value in 9.33 mg％ (pectin-degrading enzyme content)，44.70 mg％ (gelatin content) and 115.56 min (treatment time). The optimum conditions predicted for turbidity and browning color intensity of oriental melon concentration Juice were 6.6 mg％ (pectin-degrading enzyme content), 33.6 mg％ (gelatin content) and 70 min (treatment time).

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.71-74
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• 1985

In the present study, a tentative mechanism for the decomposition of the hydroperoxide formed during the thermal oxidation of an edible soybean oil was proposed. The soybean oil was thermally oxidized at $120^{\circ}C$ for 7 hrs with air injection at a rate of 120 ml/min. Through kinetic studies of the decomposition process based on the tentative mechanism and the actual experimental data obtained from the hydroperoxide decomposition at 100, 120, 150 and $180^{\circ}C$, it was found that the reaction order of the hydroperoxide decomposition in these conditions was of first order. It was also estimated that the dissociation energy for the hydroperoxide in the same conditions was 15.876 kcal/g. mol.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1759-1766
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• 2013

In this study, the optimal conditions for salmon hydrolysate using squid liver and compositional properties of hydrolysate were investigated. The optimal conditions were $55^{\circ}C$, pH 5.5 and 0.66~0.67% (w/w) in the ratio of squid liver to acidic and thermal treated salmon muscle. The free amino acid of hydrolysate from the acidic treated salmon muscle was higher than that of hydrolysate from the thermal treated salmon muscle, while the total amino acid and mineral were high in the acidic treated salmon muscle. Furthermore, cadmium of hydrolysate from the thermal denatured salmon muscle was below 2 ppm, and has an acceptable level as potential ingredient. The distribution of peptide molecular weight was 40.0% for 1.0~9.5 kDa, 6.7% for 0.5 kDa, and 47.4% of others in hydrolysate from the thermal treated salmon muscle. Both hydrolysates did not show any toxicity against the HepG2 cell line for up to $200{\mu}g/mL$.