• 한국식품과학회지
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• 제19권4호
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• pp.305-310
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• 1987

대두(大豆) 및 대두분(大豆粉) 저장중 총지방질(總脂肪質)의 산화지수(酸化指數) 및 지방산조성(脂肪酸組成)을 경시적으로 검토하였다. 저장기간이 경과함으로써 산(酸)값과 과산화물(過酸化物)값이 증가 되었는데, 이와같은 경향은 대두(大豆)보다 대두분(大豆粉)에서, 그리고 저장습도가 높을수록 현저하게 나타났다. 또한 포장재료는 OPP/Al/PE film을 사용함으로써 대두(大豆) 및 대두분(大豆粉)의 산(酸)값과 과산화물(過酸化物)값의 증가를 억제시킬 수 있었을뿐 아니라, 지방산의 변화도 감소되었다. 지방산조성은 저장기간에 따라 18 : 2산(酸)과 18 : 3산(酸)은 감소되었으나 포화지방산(飽化脂肪酸)은 상대적으로 증가되었다.

• Food Science and Biotechnology
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• 제15권3호
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• pp.404-408
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• 2006

Feasibility of surface plasmon resonance (SPR) method to evaluate soybean frying oil quality was evaluated. Free fatty acid value, p-anisidine value, conjugated dienoic acid content, conjugated trienoic acid content, peroxide value, iodine value, total polar compound (TPC), ratio of unsaturated fatty acid to saturated fatty acid, refractive index, dielectric constant, smoking point, and L, a, and b of Hunter color system were selected as parameters related to conventional evaluation of soybean frying oil quality. SPR scale mapped with conventional quality parameters well described free fatty acid value, conjugated dienoic acid content, dielectric constant, TPC, and b of Hunter color system, as shown by correlation and linear regression analyses.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제10권S_4호
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• pp.165-172
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• 2001

We investigated the optimal experimental conditions and reaction kinetics for the decompositions of PCE, TCE, naphthalene, and chloroform using conventional Fenton oxidation process. Additionally, the influence of pH on the decompositions of PCE was also evaluated. The results indicated that the optimal pH value was around 3. The dosage of Fenton's reagent and the molar ratio of hydrogen peroxide to ferrous ion for an approximately complete decomposition was found to depend on the properties of the organic compound. Due to their unsaturated structures, the results show that PCE, TCE, and naphthalene could be all effectively decomposed by Fenton's reagent oxidation. Their unsaturated structures could be mostly destoyed within first 1-2 minutes at a low dosage with an certain molar ratio of hydrogen peroxide to ferrous ion. However the saturated compound such as chloroform was more difficult to decompose even with a relatively high dosage of Fenton's reagent.

• 방사선산업학회지
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• 제8권2호
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• pp.105-109
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• 2014

This study was conducted to investigate the sensitivity of Arthrobacter sp. PAMC 25486 to various mutagens. ${\gamma}-ray$, UV-ray, Ethyl methane sulfonate (EMS) and hydrogen peroxide ($H_2O_2$) were used as mutagen, and the survival rate of Arthrobacter sp. was measured at various doses of ${\gamma}-ray$ and UV-ray, and concentrations of EMS and $H_2O_2$. Decimal reduction dose ($D_{10}$ value) of Arthrobacter sp. was determined 370 Gy for a gamma irradiation treatment, 0.019 J for a UV ray, 2.5 mM for EMS, and 230 mM for $H_2O_2$. This result will be applied for the development of superior mutant strain of Arctic bacteria producing valuable compounds.

• 대한화학회지
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• 제48권5호
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• pp.491-498
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• 2004

흑염소의 간-조직과 ferrocene을 탄소반죽 전극에 고정하여 과산화수소를 정량할 수 있는 전극을 만들었다. Ag/AgCl 전극에 대하여 $-0.3{\sim}+0.0\;V$의 전위 범위에서 전극의 감도를 관찰하였으며 전극의 감응시간은 12 s로 나타났다. 전극의 검출한계는 2.25${\times)10^{-6}M$ (S/N＝3)이었으며,1.0${\times}10^{-2 }$M 과산화수소를 이용해 15회 반복 측정한 결과, 상대표준편차는 1.87%이었다. 또한, 방해물질의 영향도 없는 것으로 나타났다. 효소전극의 감도는 19일 사용 후 50%로 감소하였다.

• 한국식품과학회지
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• 제36권6호
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• pp.885-892
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• 2004

본 실험에서는 성장기용 조제식에 함유된 유지를 대상으로 전위차 적정법 및 뷰렛 적정법에 의한 과산화물가를 측정하고 그 측정불확도를 비교하여 산정하였다. GUM(Guide to the expression of uncertainty in measurement) 및 Draft EURACHEM/CITAC Guide의 이론에 기초하여 측정불확도를 구하였으며, 불확도 인자로서 적정액의 농도, 시료량 및 적정량 등이 작용하였다. 뷰렛적정에 의한 과산화물가 측정값과 확장불확도는 $2.05{\pm}0.17\;meq/kg$ 으로 표현되었으며, 전위차적정에 의한 경우는 $1.96{\pm}0.07\;meq/kg$ 으로 표현되었다. 적정과정에서의 측정불확도가 전체불확도의 대부분을 차지하였으며, 전위차적정법에 의한 측정불확도는 뷰렛적정법에 의한 경우보다 낮게 나타나 과산화물가가 낮은 시료의 측정시에 바람직한 측정방법으로 사료되었다.

• Applied Biological Chemistry
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• 제37권5호
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• pp.320-325
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• 1994

볏짚의 사료가치를 증진시키기 위하여 알카리성 과산화수소를 이용하여 볏짚에 대한 처리수준별 화학성분의 변화와 in vitro 소화율을 조사 검토하였다. $H_2O_2(pH 11.5)$의 처리농도를 증가시킬수록 neutral detergent fiber(NDF), acid detergent fiber(ADF), hemicellulose, cellulose 및 lignin이 감소하였으며 $H_2O_2(pH 11.5)$를 처리한 후 수세시는 농도가 증가할수록 NDF, hemicellulose 및 lignin은 감소한 반면 ADF, cellulose, 회분은 증가하였다. 알카리성 과산화수소의 농도를 4%로 조정하여 처리하였을 때 pH는 $11.5{\sim}12.5$에서, 온도는 $55^{\circ}C$에서 세포벽구성물질의 분해에 효과적이었으며, 4% $H_2O_2(pH 11.5)$ 처리시 볏짚의 크기가 작을수록 잔류건물 중, hemicellulose, cellulose 및 lignin이 감소하였다. 알카리성 과산화수소의 처리에 의한 in vitro 소화율은 처리농도 및 pH가 증가할수록 볏짚의 크기가 작을수록 증가하였다.

• 한국축산식품학회지
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• 제37권2호
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• pp.305-312
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• 2017

This study was conducted to establish the shelf-life of a milk beverage product supplemented with coffee extracts. Qualitative changes including peroxide value (PV), microorganism content, caffeine content, and sensory evaluation were measured periodically in beverages kept at 10, 20, and $30^{\circ}C$ for 8 wk. Lipid oxidation of the product was measured by peroxide value analysis, and apparent changes were observed during a 4 wk storage period. Caffeine analysis revealed that the changes in caffeine content were negligible during the storage period. Total aerobic bacteria, Escherichia coli, yeast, and mold were not detected in the products during an 8 wk storage period. Sensory evaluation revealed that after 4 wk of storage overall acceptance was less than 3 points on a 5-point scale. In this study, PV was used as an indicator of the shelf-life of the milk beverage product. PV analysis revealed that a value of 20 meq/kg was the end of the shelf-life using the Arrhenius equation and the accelerated shelf-life test (ASLT). Assuming that the beverages are kept at $4^{\circ}C$ during distribution, calculation of when the PV reached the quality limit point (20 meq/kg) was done with the equation ln(PV) = 0.3644X - 2.21834 and, using that equation, $PV=e^{0.3644X-2.21834}$ was calculated. Therefore, 14.3086 wk was determined to be the shelf-life of the milk beverage supplemented with coffee when stored at $4^{\circ}C$.

• 한국식품과학회지
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• 제35권3호
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• pp.347-352
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• 2003

본 연구는 다양한 볶음 조건에서 볶지 않은 쌀눈과 볶은 쌀눈의 품질 특성을 조사하기 위하여 관능검사, 색, tocols 함량 및 과산화물가를 측정하여 평가하였다. 관능검사와 색으로 선정된 쌀눈의 가장 기호도가 우수한 최적 볶음 조건은 $170^{\circ}C$ 20분, $180^{\circ}C$ 10분, $190^{\circ}C$ 6분이었다. 쌀눈의 Hunter a 값은 볶음 온도와 시간이 증가할수록 증가하였던 반면 L값은 볶음 과정이 진행될수록 감소하였다. 지질산화안정성에 있어서는 볶지 않은 쌀눈이 볶은 쌀눈보다 안정하였으며, $60^{\circ}C$에서 저장 9일 후 POV는 볶지 않은 쌀눈의 과산화물가는 2.0 meq/kg인데 반해 $170^{\circ}C$ 20분 처리구는 145.6 meq/kg, $180^{\circ}C$ 10분 처리구는 169.5 meq/kg, $190^{\circ}C$ 6분 처리구는 182.9 meq/kg으로 과산화물의 생성 속도가 현저하게 다름을 보여주었다. 또한 모든 쌀눈 처리구에서 4가지의 tocopherol과 3가지의 tocotrienol이 확인되었으나 ${\beta}$-tocotrienol은 검출되지 않았다. 쌀눈의 주요 tocols는 ${\alpha}$-tocopherol과 ${\alpha}$-tocotrienol이었으며 $60^{\circ}C$ 저장 중 모든 볶음 처리구에서 tocol isomer의 영향은 ${\alpha}$-tocopherol이 가장 현저한 감소를 보인 반면 ${\beta}$-tocopherol과 ${\gamma}$-tocopherol은 서서히 감소하였다. ${\delta}$-tocopherol은 tocopherol 이성체 중에 가장 높은 안정성을 보였으며 저장일별 tocotrienol 이성체들의 지질산화안정성도 tocopherol과 유사한 경향을 보였다.

• 한국식생활문화학회지
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• 제31권2호
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• pp.178-187
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• 2016

The principal objective of this study was to investigate the quality characteristics of Yukwa prepared with chlorella powder. The tested concentrations of chlorella powder were 0, 1, 2, and 3%. As more chlorella powder was added, spread ratio, moisture content, and volume increased, whereas L-value and a-value decreased and b-value increased. The hardness of Yukwa made with 3% chlorella powder was highest among the samples. The results of the sensory evaluation test show that Yukwa with 1% chlorella powder was significantly more preferable in term sof overall acceptability. The acid value and peroxide values were lower in Yukwa prepared with chlorella powder than the control. Yukwa prepared with chlorella powder showed strong inhibition of lipid oxidation. Thiobarbituric values were lower in Yukwa prepared with 2% chlorella powder compared to Yukwa prepared with 1% and 3% chlorella powders and control Yukwa. These results suggest that chlorella powder can be applied to Yukwa for high quality and functionality.