• 대한가정학회지
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• 제24권4호
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• pp.75-84
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• 1986

The followings are the results of the study on decomposition of oil during the process of frying hot-dogs with soybean oil. First, the oil was heated repeatedly for six days, four hours two session per day. Then the oil was observed when heated under identical condition except for the exclusion of the frying ingredients. And the oil itself was heated constantly for a period of 48 hours. 1. The AV and Carbonyl Value of all frying oils increased with each use (but the oil in which frying ingredients with all other oils) 2. All frying oils showed a tendency to increase initially, then decrease their POV and TBA Number during their heating process. 3. The IV of all oils showed a slight decrease except for oil with frying ingredients added, with showed a substantial decrease. 4. Oil with frying ingredients showed a substantial increase in its oxidized fatty acid level, and others showed a tendency to increase according to the frying time. Decomposition of soybe an oil during the process of frying hot-dogs was studied. Three treatment was performed first, the oil was heated (with hot-dogs) repeatedly four hours in each session, two sessions per day for six days. Second, the oil was heated without hot-dogs under identical condition, Third, the oil was heated constantly for 48 hours.

• 대한가정학회지
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• 제24권1호
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• pp.59-64
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• 1986

The contents of proximate components of the polished adn unpolished Job's tears, Coix agrestis, were determined. And also the phisical and the chemical properties of fatty acids composition and the oxidative rancidity of the crude oil extracted from Job's tears were examined. RESULTS : 1.The contnets of moisture, total ash, crude protein, crude fat, and carbohydrate in Job's tears were shown to be about 9.2%, 2.1~5.0%, 19.5~20.8%, 3.7~7.2%, 60.7~67.0%. 2. The average values of specific gravity, refractive index iodine value, saponification value, acid value of the crude oil extracted from Job's tears were 0.917~0.920, 1.47574, 107~111, 198~199, 1.3~2.0, respectively. 3. The fatty acids composition in the crude Job's tears oil showed oleic acid 48.97~49.97%, linoleic acid 37.33~36.16%, palmitic acid 13.70~13.87%. 4. Generally, the peroxide values and thiobarbituric acid values of the Job's tears oils and control during 40 storage days at 40±1℃ showed very low increase. After 32 days, the peroxide values and TBA values of soybean oil showed higher than those of the Job's tears oils. Conclusively, the Job's tears oils were shown to be more stable than the soybean oil.

• 한국식생활문화학회지
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• 제34권1호
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• pp.68-74
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• 2019

This study was conducted to evaluate the effects of adding gradually increasing concentrations of turmeric extract (0, 0.1, 0.2, and 0.4%) to smoked duck meat on its chromaticity, antibiosis, and antiseptic degree against food poisoning bacteria, number of bacteria, lipid rancidity, sensory evaluation, and preference. The brightness, red color intensity and yellow color intensity changed significantly when 0.2% turmeric extract was added and the sodium nitrate concentration was reduced. Additionally, no antibiosis or antiseptic activities against food poisoning bacteria were observed in any turmeric treated samples, whereas the number of bacteria was increased in control samples compared to turmeric treated samples after 10 days of preservation. The TBARS value decreased during storage when turmeric extract concentration increased, resulting in positive sensory evaluation of its color, succulence, taste and hardness. In the preference test, the surface and meat color increased as the concentration of turmeric extracts increased. Hardness was highest at 0.2%, whereas taste was highest between 0.2 and 0.4%. The overall preference test was highest for the 0.2% extract samples. Overall, the results indicated that addition of 0.2% turmeric to smoked duck meat will lead to better nutrition, function, and overall preference.

• 한국식생활문화학회지
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• 제25권3호
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• pp.324-333
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• 2010

Off-flavor in foods and in raw materials is quite concerning, as it could signify deeper-rooted problems. Methods of reduction of "off-flavors" in traditional food such as Cheonggukjan and Kimchi, and in raw materials of soybean paste were studied by means of a literature review. It was found that the major components of "off-flavor" were due to butyric acid, valeric acid, alkylpyrazines, ammonia, and sulfides for Cheonggukjang, and for Kimchi were sulfur containing components such as methyl allylsulfide, dimethyl disulfide, diallyl disulfide, methyl allyl trisulfide, methyl 2-propenyldisulfide, dipropenyldisulfide. There is a demand for a scientific and systematic approach in overcoming the "off-flavor" problem. Nutritional aspects and safety should be considered. Several methods have been attempted, such as masking, binding, improving cooking process, inhibiting rancidity, and controlling the growth of micro-organism. Methods of masking were the most frequently ones used for the reduction of "off-flavor", and in some cases, othertechniques were additionally applied. The masking method would be useful in the reduction of "off-flavor" in traditional Korean foods, i.e. Cheonggukjang, Kimchi, as well as in new product development.

• 한국식생활문화학회지
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• 제25권6호
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• pp.795-800
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• 2010

The objective of this study was to develop high quality Riceyeotgangjung (RYG) with high antioxidant activity and a longer shelf-life. Spirulina (1, 2, and 3%) with added RYG was prepared, and antioxidant activities were examined under storage at $60^{\circ}C$ for 15 days. The total phenol content remaining in the spirulina with added RYG at 15 days of storage was much higher than that of fresh RYG without spirulina. The IC50 values for DPPH and hydroxyl radical scavenging activities decreased with increasing amounts of spirulina, whereas these values increased with storage time. TBA and peroxide values decreased with increasing amounts of spirulina. From these results, adding spirulina to RYG delayed lipid rancidity and prolonged shelf-life. Adding spirulina powder to RYG, which is a healthy functional food material, improved antioxidant activity and delayed deterioration during storage.

• Asian-Australasian Journal of Animal Sciences
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• 제18권11호
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• pp.1646-1654
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• 2005

The present study was carried out to develop cholesterol-reduced and gamma linolenic acid (GLA)-added butter and to examine the changes in chemical and sensory properties, and cholesterol lowering effect of GLA addition. The cholesterol removal rate reached 93.2% by $\beta$-cyclodextrin in butter before GLA addition. The thiobarbituric acid value of cholesterol-reduced and GLA-added butter increased slowly up to 4 week and plauteaued thereafter. TBA value was significantly increased with 2% GLA addition, compared with no GLA addition. The production of short-chain free fatty acids (FFA) increased with storage in all treatments. From 4 weeks storage, the amount of short-chain FFA in 2% GLA-added group was significantly higher than those in other groups. Among sensory characteristics, color, greasiness and overall acceptability were mostly affected by GLA addition, however, the rancidity value of 2% GLA addition was significantly different from those of control and GLA-unadded and cholesterol-reduced butter at 0, 6 and 8 week storage. Among groups, no difference was found in texture in all storage periods. The smallest increase of total blood cholesterol in rats was found in the group fed 2% GLA-added and cholesterol-reduced butter for 8 week, compared with that in controls. The present results showed the possibility of cholesterol-reduced and GLA-added butter development without much difference in chemical, rheological and sensory properties, and indicated a slow increase effect on blood total cholesterol in rats.

• Journal of Animal Science and Technology
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• 제58권8호
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• pp.31.1-31.8
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• 2016

Background: Plasma protein hydrolysates have been shown to possess antioxidant activity. However, no report has yet to examine the antioxidant effects of injection of plasma protein hydrolysates on meat quality. Therefore, in this study, the effects of injection of hydrolysis plasma protein solution on meat quality and storability were investigated in porcine M. longissimus lumborum. Methods: Twelve pigs were randomly selected at a commercial slaughter plant and harvested. Dissected loins were injected with one of five solutions: C- control (untreated), T1- 10 mM phosphate buffer solution (PBS), T2- 10 mM PBS with 0.01 % butylated hydroxytoluene, T3- 10 mM PBS with 5 % plasma proteins, and T4- 10 mM PBS with 5 % hydrolysis plasma proteins. Results: T3 and T4 induced greater reduction in protein content of the loin muscle than other treatments. T2 resulted in the lowest pH as well as highest cooking loss. After a storage period of 3-7 days, both lightness and redness of meat were unaffected by all injection treatments. However, yellowness was significantly elevated by treatment with T4 relative to the control. T4 also resulted in the lowest shear force (a measure of meat toughness), suggesting improvement of texture or tenderness. Further, T4 resulted in the most stable TBARS values during storage, indicating that this treatment might retard rancidity in meat. Conclusion: Injection of porcine M. longissimus lumborum with hydrolysis plasma protein solution could improve overall pork quality, including tenderness and storability.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2017년도 춘계공동학술대회
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• pp.98-98
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• 2017

대부분의 가정과 요식업체, 식품가공업계에서 이용하고 있는 식용유지는 저장 및 가공과정 중에 산패가 빈번하게 일어나게 된다. 기존에는 유지 산패를 측정하기 위해 산가, 과산화물가 등을 측정하는 이화학적인 적정방법을 이용하였는데 실험자의 숙련도에 따라 결과의 오차가 발생할 수 있고, 반복실험으로 인한 시간과 비용이 많이 소모되는 등 여러 제약사항을 포함하고 있어 식용유지의 산패를 실시간 비파괴적으로 분석할 수 있는 기술의 개발에 많은 관심이 모아지고 있다. 따라서, 본 연구에서는 식용유지의 저장조건에 따른 산패정도를 비파괴적으로 평가하기 위한 근적외선 분광분석과 인공신경망 분석기술을 개발하여 그 실효성을 평가하였다. 식물성 식용유지인 들기름을 특정 온도에서 일정한 시간동안 저장하면서 이화학적 적정방법을 통해 산가와 과산화물가를 측정하였으며 동일한 시료의 근적외선 투과스펙트럼을 획득하였다. 수집된 정보를 이용하여 유지 산패 예측 모델을 개발하기 위해 다변량 분석기법 (주성분 회귀분석, 최소자승 회귀분석과 인공신경망 분석)을 적용하였다. 분석 결과, 인공신경망 분석모델이 산가 ($R^2_{tra}:0.9037$, $R^2_{val}:0.8175$, $R^2_{test}:0.8555$)와 과산화물가 ($R^2_{tra}:0.9210$, $R^2_{val}:0.9341$, $R^2_{test}:0.8286$)의 예측 성능이 가장 우수한 것으로 확인되었다. 본 연구의 결과들은 농산물과 식품의 성분 측정뿐만 아니라 다른 산업분야에서도 유용하게 활용될 수 있을 것으로 기대되어진다.

• 대한가정학회지
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• 제33권6호
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• pp.245-253
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• 1995

The purpose of this study was to investigate the fatty acid composition and the rancidity of commercial deep-fat fried foods in Kangreung. the 7 kinds of samples were purchased form snack corners in 3 markets at AM 10 and PM 6 o'clock. The acid value, peroxide value and TBA value of the deep-fat fried foods were determined and the fatty acid composition were analyzed. The range of acid value was 0.45∼1.79, that of peroxide value was 1.24∼8.64meq/㎏,and that of TBA value was 12∼140 in all samples. There was significant difference in most of all samples by purchasing time and kinds of samples. But there was not specific tendency by purchasing times in each sample. Most of the acid value, peroxide value and TBA value of the samples fried with meats or sea foods showed higher value than the that of samples fried with vegetables or seaweeds. The fatty acid composition of the total lipids in the deep-fat fried foods were similar to one another. The major fatty acids were linoleic acid(C18 : 2) , oleic acid(C18 : 1) in order of content. Minor fatty acids were palmitic acid(C16 :0), linolenic acid(C18 : 3), stearic acid (C18 : 0) in order of content. the P/S ratio was the range of 2.12/1∼4.71/1 and the that of the samples fried with meats was the highest among samples. so there was the same tendency in this result between the chemical properties(acid value, peroxide value, TBA Value) and fatty acid composition. As a result of acid value and peroxide value in this study, the commercial deep-fat fried foods in Kangreung was safety.

• Journal of Biosystems Engineering
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• 제36권2호
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• pp.109-115
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• 2011

Drying characteristics of squids under two dry conditions were investigated using far infrared and heated air. Dry temperatures of 40, 50 and $60^{\circ}C$ with air speed of 0.6, 0.8 and 1.2 m/s were used for evaluating far infrared squid drying. Heated air squid drying at 40 and $50^{\circ}C$ with air speed of 0.8 m/s was used as a control treatment. The two drying were evaluated in terms of drying rate, color, TBA value, aerobic bacteria, cutting shear, penetration strength, and energy consumption. The drying rate of far infrared drying was relatively faster than that of heated air drying. The drying time of far infrared drying was reduced as the drying temperature increased. The color difference of far infrared dried squids was from 18.81 to 22.85, and heated air dried squid had the color different from 23.94 to 24.09. Far infrared dried squid had relatively smaller TBA values that indicate a level of rancidity. The aerobic bacteria of heated air dried squid increased from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g before and after drying, respectively. Far infrared dried squid had relatively smaller increase (from $970{\times}10^3$ to $40,000{\times}10^3$ CFU/g). The cutting shear and penetration strength for far infrared dried squids was relatively lower. In addition, far infrared squid drying consumed relatively less energy compared to heated air drying.