• Korean Journal of Food Science and Technology
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• v.44 no.4
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• pp.472-477
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• 2012

As people are being exposed to many types of fast food, rancid oil is a factor affecting public health. Monitoring of rancidity in frying oils needs to be done adequately. The chemical methods that are currently used require long periods of time and expertise. The development of a device that quickly and easily measures rancidity would be helpful to manage rancidity in frying oils adequately. Due to the fact that carbon nanotube (CNT) is sensitive to acid value, we used CNT as a sensing material for detecting oil rancidity. Polyethylenimine (PEI) was coated on CNT for stable measurements. Experiments were conducted at $100^{\circ}C$ after samples were cooled from $180^{\circ}C$. The results showed a strong correlation between acid values and resistances using CNT sensors. As the acid value of oils increased, the resistance of CNT sensors increased. Development of sensors using CNT may make it possible to determine the rancidity of frying oils in real-time and on site.

• Journal of Nutrition and Health
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• v.20 no.4
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• pp.237-245
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• 1987

Young male rats were fed for 10 and 20 days on different low-fat experimental diets ; 4% lard + 4% soybean oil, 4% sardine oil + 4% lard, 4% sardine oil with vitamin E+ 4% lard, 4% sardine oil with vitamin E+ 4% soybean oil. Lipid peroxide levels in liver were significantly higher in the sardine oil groups but the addition of vitamin Ehad no effects on the lipid peroxide values. Serum total cholesterol showed no significant difference among the groups but HDL-cholesterol in serum was increased in the sardine oil groups. However, the contents of serum triglyceride and phospholipid were unaffected by the replacement with sardine oil.

• Safe Food
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• v.7 no.1
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• pp.26-31
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• 2012

• Journal of the Korean Applied Science and Technology
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• v.4 no.1
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• pp.77-81
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• 1987

No difference was observed on autoxidative stability of triacylglycerols before and after randomyl interesterification. It indicate that randomization of the glyceride composition has no significant effect on the autoxidative stability. On the other hand, the autoxidation of randomyl interesterified vegetable oil was accelerated, caused mainly by decrease of tocopherols during the series of interesterification procedures.

• 우유
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• s.48 spring
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• pp.39-41
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• 1992

우유의 유지방을 주성분으로 하는 지방 식품인 버터는 오랜 옛날부터 제조되어 애용된 유제품 중의 하나이다. 기록에 의하여 식용으로서 뿐만 아니라 약용과, 제물로 이용될 만큼 매우 귀중하고 신성한 것으로 보고되어 있다. 반면 버터 대용품인 마가린은 유지방이 아닌 식품성 또는 동물성지방을 주원료로 하여 만든 식품으로서 1869년 프랑스의 나폴레옹3세가 프러시아와 전쟁 때 버터의 부족을 해결하기 위해 인조버터를 만들었는데 이것이 변천하여 오늘의 마가린이 되었다.

• The Microorganisms and Industry
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• v.14 no.2
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• pp.26-29
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• 1988

미생물을 이용한 유지의 생산은 동식물 유지의 대체자원으로써의 가능성 때문에 1910년대 독일에서 연구가 시작되어 현재에 이르기까지 계속되어 왔으나 현재까지의 미생물 생산공정으로는 값싼 식물성유지에 비하여 경제성이 떨어지기 때문에 공업적인 생산은 이루어지지 않고 있다. 그럼에도 불구하고 최근들어 미생물유지, 즉 단세포 유지(Singl Cell Oil) 생산에 관한 연구가 늘어나고 있는 것은 몇가지 관점에서 생각해 볼 수 있다. 첫째로는 전세계의 우지생산이 미주, 지중해 연안국및 동남아 몇개국에 국한되어 세계적인 유통이 때로는 원할치가 않아 수급과 가격의 변동이 심하고, 둘째로는 생물공학기술의 발달로 인하여 좀더 경제적인 방법으로 단세포유지를 생산할 수 있는 가능성이 증대되었기 때문이다. 또한 단세포유지는 단세포단백질과는 달리 식용, 사료용이외에 공업용 원료로도 사용될 수 있으므로 소비자들의 선호도, 법적 규제등의 문제가 상대적으로 작은 것도 한 이유가 될 것이다. 본 소고에서는 유지의 종류, 유지생합성및 축적 메카니즘, 단세포유지 발효공학및 유지추출, 단세포유지의 경제성, 단세포유지에 관한 최근의 연구동향에 관하여 살펴보기로 한다.

• Applied Biological Chemistry
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• v.42 no.4
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• pp.317-323
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• 1999

Immature plums(Prunus salicina L.) were coated with edible coatings, calcium-added methyl cellulose(CaMC) and hydroxy propyl methyl cellulose-15(CaHPMC-15). Weight loss and respiration rate of immature plums coated with CaMC and CaHPMC-15 were lower only at the earlier storage period. The titratable acidity of plums was decreased and pH was increased during storage, Soluble pectin, pectinesterase, and polygalacturonase activity as the marker of softening were commonly increased with storage time, but those increases were lower in CaMC and CaHPMC-15-coated plums. Mechanical firmness became significantly soft during storage, while the coated plums were remained harder. As a result of sensory evaluation, softening of plum tissue was found during storage, but the coated plums had the harder texture. These data suggest that the application of CaMC or CaHPMC-15 coatings into immature plums can reduce the postharvest softening during storage.

• Journal of the Korean Applied Science and Technology
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• v.35 no.1
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• pp.99-110
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• 2018

In this study, oil of Platycodon grandiflorum seeds was prepared using supercritical carbon dioxide extraction (SCE) and its physicochemical indices as a new edible oil were investigated. Compared to Soxhlet solvent extraction, SCE under the condition of 6,000 psi at $40^{\circ}C$ produced more oil, especially from the roasted seeds to 32.7%. TLC analysis showed triacylglycerols accounted for most of the oil obtained from roasted Platycodon grandiflorum seeds by SCE similarly to commercial soybean oil or perilla seeds oil. The oil had highly unsaturated lipid with considerable amount of linoleic acid(73.27%) much more than two commercial oils followed by oleic acid(13.16%). Physicochemical properties of the oil were as follows; specific gravity, 0.92; dynamic viscosity, 45.37 cP; refractive index, 1.48; color, L=47.30, a=-3.69, b=25.72; iodine value, 141.57 g $I_2/100g$ oil; saponification value, 191.21 mg of KOH/g of oil; acid value, 2.60 mg of KOH/g of oil. Among those, refractive index, viscosity and iodine value, which were related to unsaturation degree of lipid, were ranged between those of two commercial oils. The oxidation stability of oil(2.03 hr) was also ranged between less stable perilla seeds oil(1.79 hr) and more stable soybean oil(2.94 hr) based on the induction time measured by Rancimat assay. In addition to extraction yield increase, seeds roasting provided further benefits such as reductions of cholesterol ester content and acid value without change in fatty acid composition. In conclusion, oil was extracted from the roasted Platycodon grandiflorum seeds at high yield by supercritical carbon dioxide and it seemed to have proper characteristics as a edible oil.

• 농업기술회보
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• v.49 no.3
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• pp.27-28
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• 2012

유채는 유지작물로 주 용도는 기름이다. 유채기름은 튀김용과 샐러드유로 많이 쓰이며, 식용 이외에도 바이오디젤, 윤활유, 인쇄잉크, 페인트, 화장품, 플라스틱 가소제 등 공업적인 용도도 증대되고 있다. 부산물인 유채박은 가축사료와 유기질 비료로 사용되고, 유채꽃은 밀원 및 관상용으로 쓰이고 있어 그 용도는 매우 다양하다.

• Korean Journal of Food Science and Technology
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• v.24 no.4
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• pp.320-325
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• 1992

For natural antioxidant test, the Rhus javanica $Linn\'{e}$ was extracted by 75% ethyl alcohol and fractionated it by chloroform and ethyl acetate using separatory funnel and column chromatography. In the Rhus javanica L. extract, the effective material was disolved easily in ethyl acetate and chloroform. When 600 ppm of ethyl acetate fraction of the extract was added to palm oil and lard, AI(antioxidant index) of each oil was 1.60 and 3.90 respectively. The $CHCl_3$ and EtOAc fractions were more effective than whole extract of Rhus javanica L. The palm oil, lard and soybean oil containing different levels of the Rhus javanica L. extract were stored at $60^{\circ}C$ to compare their antioxidative activity. Peroxide value, acid value and TBA value of each oil were monitored. The Rhus javanica L. extract was very effective to retard oxidation of palm oil and lard. This result coincided with Ranimat test.