• 한국한의학연구원논문집
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• 제1권1호
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• pp.541-553
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• 1995

In order to study the stability of herbal oil(Yoo-Je), the Yoo-Je from walnut and safflower measured their rancidity by gas chromatographic analysis. The use of specificity of column for estimating the oxidative deterioration of Yoo-Je was attempted. These results suggested the possible implication of pentanal and hexanal as an stability index for rancidity evaluation of Yoo-Je.

• 생약학회지
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• 제54권2호
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• pp.80-87
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• 2023

Rancidity changes were examined for 6 herbal medicines, namely Persicae Semen, Armeniacae Semen, Lini Semen, Trichosanthis Semen, Arecae Semen, Myristicae Semen known to have relatively high fat content. In order to reduce rancidity of herbal medicines, samples were stored at 3 different conditions of room, refrigerating and freezing temperatures, and the rancidity was measured for 10 months with every 2 month interval. Fat content was extracted by using ethyl ether, and acid values and peroxide values, which are generally accepted indicators of fat rancidity, were measured. When storing Persicae Semen, Lini Semen and Arecae Semen at room temperature, the acid values increased as the storage period increased, and it was higher than when stored in refrigeration or freezing. The measurement of peroxide value showed more significantly higher initial degree of rancidity when Persicae Semen, Trichosanthis Semen, Arecae Semen and Myristicae Semen were stored at room temperature. It was observed that storing herbal medicines in refrigeration or freezing inhibited their rancidity compared to storing them at room temperature. To investigate the quality changes according to rancidity, the analysis of aflatoxins and indicator components showed that aflatoxins B₁ and B₂ were detected in Armeniacae Semen, Arecae Semen and Myristicae Semen, and the amount of amygdalin was well maintained within the specification standard.

• 한국응용과학기술학회지
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• 제7권2호
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• pp.91-100
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• 1990

• 한국식품저장유통학회지
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• 제19권5호
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• pp.639-644
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• 2012

본 실험은 형광분광법을 이용하여 분말화된 대두의 산패도를 유지의 추출과정 없이 직접 측정하는 방법을 확립하기 위해 실시하였다. FST와, TBA test, 산가 측정법을 이용하여 $25^{\circ}C$와 $90^{\circ}C$에서 20일 동안 저장하면서 산패도에 따라 값을 비교하였다. $25^{\circ}C$에서 저장 기간 중의 산패도는 변화가 없음을 알 수 있었다. 모든 측정치들은 초기값에 비해 20일 후의 값이 크게 차이 없이 일정한 것을 알 수 있었다. 반면 $90^{\circ}C$에서는 FST의 경우 8일에서 11일 사이에 FI값이 크게 증가하는 경향을 보인 후 일정하게 값이 증가하는 경향을 볼 수 있었는데 TBA test에서는 0일에서 꾸준하게 증가하던 값이 다시 감소하는 것을 보였으며 이는 oleic acid와 linoleic acid의 함량이 높은 대두의 특징이라 할 수 있다. 본 연구에서 실험한 시료의 경우 산가는 FST와 같은 경향을 보여주었다. 본 연구의 중요한 결과는 FST를 이용하여 대두의 산패를 분말상에서 직접 측정하는 법을 확립한 것이며 이는 일반적으로 사용되는 TBA test와 산가를 이용한 직접측정법에 비해 측정시간이 빠르며 추출과정에 의한 오차를 최소화 할 수 있음을 보여주었다.

• 한국식생활문화학회지
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• 제23권4호
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• pp.469-478
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• 2008

In this study, degree of rancidity and trans fatty acid formation were examined in fat and oils, including soybean oil (SB), canola oil (CA), corn germ oil (CO), olive oil (OL), palm oil (PO), and beef tallow (BT), during heating for 10-130 minutes at 160-200$^{\circ}C$. In order to determine the rancidity of the fat and oils, acid values (AV), iodine values (IV), viscosity, and color were measured. Changes in the amounts of fatty acids and the formation of trans fatty acids were measured using GC and HPLC. For all groups, AV increased, IV decreased, and coefficients of viscosity and color increased as the heating temperature and heating time increased, indicating there were positive correlations between the heating temperature and time and AV. In addition, all groups had similar amounts of trans fatty acids, with the exception of the beef tallow; however, its level only slightly increased with heating. The olive oil had the lowest trans fatty acid content and the lowest amount created by heating. The order of trans fatty acid amounts generated while heating was BT>PO>CO>CA>SB>OL. According to the study results, the deep frying temperature during cooking should be 160-180$^{\circ}C$ in order to reduce AV and the amount of trans fatty acids that are formed. In addition, it is better to remove beef tallow during cooking and avoid heating at high temperatures since it results in high levels of trans fatty acids. The correlation between the amount of trans fatty acids and AV was positive, while the correlation between the amount of trans fatty acids and IV was negative, indicating that AV and trans fatty acid levels increase while IV decreases as the deep frying temperature and time increase. From the results, it was found that reducing the deep frying temperature and time can lessen increases in AV and trans fatty acids, and decrease IV. Accordingly, to reduce AV and trans fatty acid formation, the ideal deep frying conditions would be to use olive oil or soybean oil rather than beef tallow or palm oil at a temperature of 160-180$^{\circ}C$.

• 한국식품조리과학회지
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• 제9권2호
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• pp.88-93
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• 1993

Semi-prepared frozen muscle foods purchased from local industry were tested for lipid oxidation. The effects of various storage conditions, cooking methods, defrosting methods and reheating methods on rancidity were examined using TBA assay and sensory evaluation. TBARS values were increased faster in cooked samples than in uncooked ones during storage periods. During refrigeration of cooked samples, TBARS values were increased significantly for 15 days (p<0.001). In defrosting experiments, refrigerated defrosting was proven to be better compared with room temperature or microwave defrosting (p<0.05). For overall explanation, stepwise regression analysis was done and the results are in this order: storage conditions, cooking methods, moisture content, and lipid content. Using these 4 variables, TBARS values could be explained by 40~53%.

• Journal of Nutrition and Health
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• 제10권2호
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• pp.27-34
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• 1977

The present study was carried out to evaluate the nutritional quality of rabbit meat protein. The composition of amino acids contained in rabbit meat was compared with those of other animal meats such as beef, pork and chicken. Also included in this study was the question whether the cooking and storage conditions affect the amino acid composition and the pepsindigestibility of rabbit meat protein. The results are summarized as follows: 1. The large variation observed from sample to sample of EAA (essential amino acid) composition in rabbit meat was found to be an interesting but peculiar property of rabbit meat protein. The most limiting amino acid of rabbit meat protein was phenylalanine, whereas methionine was the first limiting amino acid of both beef and pork proteins. Chemical scores of various meat proteins were 68, 65, 66, and 74 for rabbit meat, beef, pork, and chicken respectively. 2. In pan roasting, the EAA damaged most by heat was methionine (15%). When cooked after two months of frozen storage, lysine decreased most. 3. Higher pepsin digestibility was obtained by cooking rabbit meat after seasoned in alcohol, ginger juice, and other spices compared with various other cooking conditions without seasoning. The pepsin digestibility value was even higher for the seasoned meat than for the raw meat. 4. Among various meats tested the rabbit meat showed the lowest pepsin digestibility. 5. A simple measurement of released methionine could be used to determine relative digestibility instead of measuring $NH_2-N$ content after pepsin digestion. From all the results obtained in this study it can be concluded that rabbit meat is a good Protein food item when used fresh and stored properly to prevent rancidity problems. It is suggested to study further the peroxidation effect of unsaturated fatty acids on protein quality. This study was supported by the Ministry of Science and Technology in Korea.

• 한국식품과학회지
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• 제22권2호
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• pp.140-144
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• 1990

저장기간을 달리 ($20^{\circ}C$-단기간, $4^{\circ}C$-장기간)하여 Na-acetate와 Ca-chloride를 단독 혹은 혼합하여 첨가한 깍두기의 저장성을 조사하기 위하여 pH, 산도 및 관능적 특성을 평가하였고 Instron을 이용하여 경도를 측정하였다. $20^{\circ}C$ 또는 $4^{\circ}C$에서 저장하는 동안 Na-acetate 첨가 및 그 첨가수준이 증가될수록 pH 감소는 억제된 반면 적정산도가 높게 나타나는 완충효과를 관찰하였다. Ca-chloride 첨가시 경도와 짠맛이 증가되었고 특히 이 두 가지 첨가제를 동시에 사용한 NaA Ca군에서 경도향상 효과기 상승되었으며, 0.3% Na-acetate 첨가로는 신맛이 감소되지 않았으나 0.6%로 첨가량을 증가시킨 경우에 신맛 감소효과가 현저하게 나타났다. Instron 측정결과 첨가제의 종류에 따라 시료의 변형을 위해 요구되는 힘의 크기가 달랐으며, $4^{\circ}C$ 및 $20^{\circ}C$저장시료 모두 Puncture test 보다 Compression test에 의해 시료들간의 경도차이가 확실하게 관찰되었고 관능검사와 유사한 경향을 나타냈다.

• 한국작물학회지
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• 제63권4호
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• pp.338-359
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• 2018

Soybean (Glycine max L.), a major part of Asian diet, is consumed primarily for its nutritional value. However, poor storage stability often leads to loss of nutritional value or deterioration in quality. This study focused on the storage stability of soy flour obtained from raw and roasted "Saedanbaek" soybeans packed in polyethylene (PE) and polypropylene (PPE) film bags that were stored at $4^{\circ}C$, $20^{\circ}C$ and $45^{\circ}C$ for 48 weeks. The early acid values (diene and p-anisidine) of raw soybean flour (RSF) at high temperature (HT) were higher than those at refrigerated temperature (RFT) and room temperature (RT) during 48 and 12 to 36 weeks, respectively. In the case of roasted soybean flour (ROSF), which was stored at RFT and RT, the acid and conjugated diene values gradually increased after 24 weeks. In RSF, the peroxide value increased since the beginning of the $24^{th}$ week. The p-anisidine value also increased during 12 to 36 weeks but was much lower than the values obtained from HT storage. As the peroxide values decreased, the p-anisidine values increased, indicating an inverse relationship. Lipoxygenase activity of ROSF at all storage conditions was lower than RSF. Several differences were observed between the packing materials used. This study could, therefore, provide useful information for the industrial use of soybean flour (SF).

• 한국식생활문화학회지
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• 제6권3호
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• pp.237-244
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• 1991

김치에 인삼 2% 및 4%를 첨가하여 $20^{\circ}C$에서 9일간 저장하면서 숙성기간별로 pH, 산도, 염도와 환원당의 변화를 관찰하고, Instron에 의한 경도측정, HPLC에 의한 유기산 분석 및 관능검사로 가식기간과 기호성에 미치는 영향을 연구하였다. 시료김치는 약 2.3% 정도의 염도를 유지했으며 발효기간 중 인삼 첨가군이 pH, 환원당함량 및 기계적 측정에 의한 경도가 높게 나타났고 산도는 낮게 나타났다. 유기산 분석결과 oxalic acid, lactic acid, malic acid의 함량이 많았으며 발효가 진행됨에 따라 succinic acid, lactic acid와 acetic acid는 증가하고 oxalic acid는 크게 변하지 않았으며 tartaric acid와 malic acid의 함량은 감소하였다. 관능검사결과 인삼첨가군이 대조군보다 높은 경도를 나타냈으며 감칠맛과 탄산미가 좋게, 신맛과 이취가 적게 평가되었으며, 인삼으로 인한 쓴맛과 전체적 취식특성이 좋게 평가된 것으로 보아 인삼의 첨가가 김치의 기호성을 증대시킬 수 있을 것으로 여겨진다. 또한 관능검사와 분석한 성분과의 상관관계를 알아본 결과 김치의 기호도는 이취, 탄산미, 신맛, 그리고 감칠맛에 의해 결정됨을 알 수 있다. 결국 김치에 인삼을 첨가함으로써 기호성을 증대시키고 가식기간을 연장할 수 있었으며, 인삼첨가군 사이의 유의적인 차이가 없는 것으로 보아 인삼 2% 첨가군이 기호성 및 경제성에 있어서 우수한 것으로 나타났다.