• 대한가정학회지
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• 제30권2호
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• pp.61-71
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• 1992

This study was designed to evaluate the anti hypercholesterolemic effect in either soybean oil or lard containing hypercholesterol diet in rats. Rats were fed, ad libitum, for 5 weeks with diets containing 0, 5, 10% of L.edodes in either soybean oil or lard with 1% exogenous cholesterol. Forty-two male sprague-dawley rats weighing 71.6$\pm$8.1g were divided into 6 groups. The results of this study were summairzed as follows: 1. Weight gain, total feed intake, feed intake efficiency ratio, total calorie intake and calorie efficiency ratio during five weeks showed significant difference among groups. The lowest value was found in soybean oil ＋ L.edodes-free group and the highest value was found in lard ＋ L.edodes-free group. The weight of organs were significantly higher in lard groups than soybean oil groups. 2. The contents of serum triglyceride showed significant difference kinds of lipids. It tended to be lower soybean oil groups than lard groups. It was difference with dietary L.edodes levels in soybean oil groups. The contents of total serum cholesterol showed significant difference by kinds of lipids, it was lower soybean oil groups than lard groups. But it was not differ with dietary L.edodes levels in soybean oil groups. 3. The contents of total liver cholesterol showed no difference kinds of lipids. And it was lower in soybean oil groups than lard groups. This result showed that the soybean oil decreased the contents of total liver cholesterol.

• 한국조리학회지
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• 제17권4호
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• pp.316-325
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• 2011

튀김 기름은 튀김음식의 품질에 중요한 인자중의 하나이다. 본연구의 목적은 전통적 튀김기와 개량식 튀김기를 사용하여 4일간 연속적으로 사용한 튀김 기름의 품질을 분석하는데 그 목적을 지닌다. 돈가스를 튀긴 후, 뒤김 기름은 일부를 유리병에 분석을 위해 수집하여 여러 이화학적 특성의 실험에 사용하였다. 전통적 튀김기를 사용한 튀김 기름은 사용횟수에 따라 색과 접도 값이 개량식으로 튀긴 기름에 비하여 유의적으로 증가하였다. 유리지방산의 정도와 관련된 산가의 경우, 전통식 튀김기를 사용한 튀김 기름은 개량식 튀김기를 사용한 튀김 기름에 비하여 유의적으로 증가하였다. 반면 이중결합의 농도와 연관이 있는 요오드가는 전통식 튀김기를 사용한 튀김 기름의 값이 개량식을 사용한 튀김 기름에 비하여 유의적으로 감소하였다. 1차지방산화의 지표인 과산화물가의 경우, 전통식 튀김기와 개량식 튀김기를 사용한 튀김기름 모두에서 2일까지는 유의적으로 그 값이 증가하였으나 3 일 부터는 그 값이 감소하였다. 이는 형성된 과산화물이 불안정한 형태이므로 분해를 통하여 다른 2차 산화로 진행된 것으로 사료된다. 2차 산화의 지표인 p-Anisidine 값을 확인한 결과, 전통식 튀김기를 사용한 튀김 기름은 개량식을 사용한 튀김 기름에 비하여 시간 의존적으로 유의적 증가를 나타내었다. 따라서 개량식 튀김기를 사용한 튀김 기름이 유리지방산과 산패의 정도가 전통식 튀김기를 사용한 튀김 기름에 비하여 늦게 진행된는 것으로 사료된다.

• 한국환경과학회지
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• 제17권2호
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• pp.211-224
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• 2008

Characteristics of the esterification reaction between free fatty acid in rice bran oil and methanol was investigated in the presence of catalysts, such as PTS(p-toluene sulfonic acid), Amberlyst 15 dry and SCX(silica gel based strong cation exchange resin). While reaction temperature was kept constant at $65^{\circ}C$, initial feed content of free fatty acid was varied from 100% to 1% by addition of pure free fatty acid which was previously made from rice bran oil. Also, the effect of mole ratio of methanol to fatty acid on the final conversion was examined. When esterification of pure free fatty acid was catalyzed by several acids, final conversions were increased in order of Amberlyst 15 dry, SCX and PTS. Using PTS catalyst, initially the reaction proceeded in homogeneous 2nd oder reaction mechanism. However, phase of reaction mixture changed from homogeneous to heterogeneous along the reaction time and then reaction rate was retarded by mass transfer resistance of methanol. Final conversion of free fatty acid in reaction mixture was depended on initial feed content of free fatty acid, and had maximum value at 30% of initial feed free fatty acid content for all kinds of catalysts used. And the final conversion was increased with mole ratio of methanol by the improvement of reaction rate. When initial feed free fatty acid content below 10% and the reaction was catalyzed by PTS, concentration of free fatty acid in reaction mixture was increased in the middle of reaction time by hydrolysis of triglyceride in reaction mixture. Also, if silica gel was added into the reaction mixture which had initial feed free fatty acid content below 50%, final conversion was increased by the adsorption of moisture produced. The SCX catalyst made the esterification reaction of free fatty acid to progress like in case of PTS catalyst. However, when initial feed free fatty acid content below 10%, concentration of free fatty acid in. reaction mixture was decreased monotonically and not increased in the middle of reaction time on the contrary to the case of PTS. Thus, SCX catalyst accomplished more high value of final conversion than PTS catalyst for the initial feed fatty acid content range from 50% to 5% In case of initial feed free fatty acid content of 1% and mole ratio of methanol was 2, concentration of free fatty acid in reaction mixture increased over the initial feed free fatty acid content for all kind of catalysts used. Although SCX catalyst was added into reaction mixture which had 1% of initial feed fatty acid content, final conversion was hardly raised by mole ratio of methanol.

• Tribology and Lubricants
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• 제23권6호
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• pp.306-311
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• 2007

This paper presents the friction characteristics of pb-fres pin bushing bearings for an automotive gasoline engine. The external load is 100 N to 600 N and the speed of the pin bushing bearing is 1000 rpm to 3000 rpm against the rubbing surfaces. And the contact modes of rubbing surfaces between a piston pin and a pb-free pin bushing specimen are a dry friction, an oil lubricated friction and a mixed friction that is starved by a lack of engine oil. Two influential factors of a contact rubbing modes and a material property are very important parameters on the tribological performance of a friction characteristic between a piston pin and a pb-free pin bushing. The experimental result shows that the pin bushing speed of 2000 rpm shows a typical oil film lubricated sliding contact mode in which means that as the applied load is increased, the friction loss is increasing. But other contact mode depending on the speed and the load may affect to the fiction coefficient without a regular and uniform trend. In summary, the oil lubricated rubbing surface definitely decreases a running-in period in short and increase oil film stiffness, and this may leads the reduction of a friction loss.

• 한국식품영양학회지
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• 제7권4호
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• pp.318-322
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• 1994

Aluminium alloy, comprising water, silicone manganese and porous aluminium carrier added into soybean oil in order to investigated its effect on polar lipid content, polymer content, conjugated dienoic acid and free fatty acid value during deep-fat frying at 185$^{\circ}C$. Increase rates of polar lipid and polymer content of the frying ell were reduced about one thirds of the oil without aluminium alloy during deep-fat frying. The aluminium alloy, however, have no significantly effect to inhibit the increase of conjugated dienoic acid and free fatty acid value. Treatment of the frying oil with aluminium alloy was found to be able to inhibit polymer and polar lipid formation.

• 동아시아식생활학회지
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• 제23권4호
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• pp.470-476
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• 2013

The property of deep frying oil is one of the important factors in fried food quality. The purpose of this study is to identify the quality of deep frying oil in continuous usages for 4 days by two types of fryers: traditional deep-fat fryer and modified oil-water fryer. After frying pork cutlets, the frying oil was kept not only for several physical analyses such as color, viscosity, and water content but also for the quality analyses of frying oil, such as free fatty acid, double bond changes and oxidative rancidity formation. The oil fried in a traditional deep-fat fryer was significantly increased in terms of physical values including moisture content, viscosity, and color, compared to those of the modified fryer, continuously for 4 days. The oil fried by a traditional deep-fat fryer exhibited a significant increase in its free fatty acid content compared to that fried by a modified oil-water fryer, while the iodine value was significantly decreased in the oil fried by a traditional deep-fat fryer when compared to control oil and oil fried by the modified oil-water fryer. In the peroxide value as an indicator of primary oxidation products, the oil fried by both fryers was significantly increased till the second day but decreased in value after the third day because of unstable hydroperoxide decomposition. The p-anicidine value is used as an indicator of secondary oxidation products, the oil fried in a traditional deep-fat fryer was significantly increased in value compared to that of a modified oil-water fryer.

• Journal of Biosystems Engineering
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• 제41권3호
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• pp.177-183
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• 2016

Purpose: Mee (Madhuca longifolia) is an economically important tree growing throughout Sri Lanka. Its importance is mainly attributed to its oil with high nutritional and medicinal values. However, an inefficient extraction method limits its use. This study revealed the possibility of extracting oil from mee seeds by using a screw-type oil expeller. Methods: A popular screw-type oil expeller was used in the experiment. Extract bar clearance and speeds of the main spiral shaft were altered to increase the oil expelling efficiency of the machine. The quality of refined oil at the optimum oil yield was determined by measuring the refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity. Results: An optimum yield of 35% oil was obtained when the machine capacity was 30 kg/h and energy consumption was 0.13 kWh/kg. This optimum machine condition was observed at an extract bar clearance of 0.5 mm and a main spiral shaft speed of 90 rpm. The refractive index, saponification value, iodine value, unsaponifiable matter, free fatty acid, and specific gravity of the oil were 1.4, 203, 59, 3.5%, 0.2%, and 0.907 g/cm3 respectively. Color of the mee oil was closer to yellow, which is revealed by the lightness value (L) of 24.93 and positive value (b) of 11.81. Conclusion: The screw-type oil expeller can be used for economically extracting mee oil on a commercial scale.

• 셀메드
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• 제6권2호
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• pp.11.1-11.7
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• 2016

The aimed of the presence study was to determine the antiulcer potential of virgin coconut oil (VCO), either extracted by wet process (VCO_A) or fermentation process (VCO_B), and to compare their effectiveness against the copra oil (CO) using the HCl/ethanol-induced gastric ulcer model. Earlier, the oils underwent chemical analysis to determine the free fatty acids composition, physicochemical properties and anti-oxidant capability. In the antiulcer study, rats (n=6) were pre-treated orally for 7 consecutive days with distilled water (vehicle), 100 mg/kg ranitidine (positive group) or the respective oils (10, 50, and 100% concentration). One hour after the last test solutions administration on Day 7^th, the animals were subjected to the gastric ulcer assay. Macroscopic and microscopic analyses were performed on the collected rat's stomachs. From the results obtained, the chemical analysis revealed i) the presence of high content of lauric acid followed by myristic acid and palmitic acid in all oils and; ii) the significant (^*p< 0.05) different in anisidine- and peroxide-value, percentage of free fatty acid, total phenolic content and total antioxidant activity among the oils. The animal study demonstrated that all oil possess significant (^*p< 0.05) antiulcer activity with VCO_B being the most effective oil followed by VCO_A and CO. The macroscopic observations were supported by the microscopic findings. Interestingly, all oils were more effective than 100 mg/kg ranitidine (reference drug). In conclusion, coconut oils exert remarkable antiulcer activity depending on their methods of extraction, possibly via the modulation of its antioxidant and anti-inflammatory activity.

• 한국수산과학회지
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• 제20권2호
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• pp.146-151
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• 1987

정어리유의 산화 안정성과 지질추출시에 첨가한 BHA에 의한 저장중의 산화방지효과를 정토하고 산화로 인한 지방산 조성의 면화를 조사한 결과를 요약하면 다음과 같다. 1. BHA는 유리 지방산의 생성을 현저히 억제하는 효과가 있었다. 2. BHA는 과산화물 생성을 억제하였으며 특히 카르보닐 화합들의 생성을 아주 강하게 억제하였다. 즉 BHA는 과산화을 분해를 억제하는 작용이 있었다. 3. 정어리유는$C_{20:5}$와 $C_{22:6}$의 함량이 $23\%$ 이상으로서 매우 높았다. 4. 산화에 의한 지방산의 감소는 polyene 산에서 급격하였으며 특히 $C_{20:5}$와 $C_{22:6}$산이 급격히 감소하였다. BHA 첨가는 $C_{22:5}$와 $C_{22:6}$산의 산화를 크게 억제 할수 있었다.

• 한국식품영양과학회지
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• 제33권3호
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• pp.587-592
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• 2004

혈중 콜레스테롤 농도를 저하시키는 건강지향적인 불포화 지방산을 다량 함유한 옥배유로 원료유 지방을 표준화하여 cholesterol free Mozzarella cheese제조 후 특성을 살펴 보았다. 치즈 제조용 원료유는 안정성이 있었고, 최종 시료인 치즈에서 휘발성 유리지방산은 콜레스테롤 상승에 영향을 미치는 palmitic acid가 일반 치즈인 대조구에서 가장 높게 측정된 반면에 실험구인 옥배유를 첨가하여 만든 치즈는 동맥경화 및 성인병 등의 예방, 치료에 도움을 주는 linoleic acid 조성 이 가장 높게 나타나 영양학적으로 우수한 결론이 돌출되었다. 포화지방산에 대한 불포화지방산의 비율은 대조구가 7:3, 옥배유를 첨가하여 만든 치즈가 2:8로 나타났으며, 콜레스테롤은 대조구의 43.58 mg/100 g에 비해 옥배유를 첨가하여 만든 치즈는4.34 mg/100g만 측정되어 건강에 유의한 결과가 나타났다. 결과적으로 본 연구는 혈중 콜레스테롤 저하효과를 나타내는 휘발성 유리지방산을 다량 함유하고, 콜레스테롤 함량이 대조구의 10%수준인 영양학적으로 우수한 건강지향적인 cholesterol free Mozzarella cheese를 제조할 수 있었다.