• Korean Journal of Food Science and Technology
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• v.17 no.5
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• pp.361-370
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• 1985

The effect of major ingradients (Water, Soybean oil, Na-caseinate, Soybean protein isolate, Corn starch. Lactic acid and disodium phosphate) on the textural properties of imitation cheese were studied by response surface methodology and evaluated by contour diagram. The hardness of imitation cheese was directly influenced by the contents of water, oil and Na-caseinate and also affected by the interactions between water and oil and corn starch and lactic acid/phosphate. The adhesiveness was strongly affected by the interactions between caseinate and lactic acid/phosphate, SPI and corn starch and corn starch and lactic acid/phosphate. The springiness was directly influenced by the contents of oil, caseinate and lactic acid/phosphate, and also affected by the interactions between SPI and lactic acid/phosphate and corn starch and lactic acid/phosphate. The melting property was strongly influenced by the contents and interactions of lactic acid/phosphate.

• Food Science and Biotechnology
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• v.18 no.2
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• pp.299-306
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• 2009

The purpose of this study was to prepare stable water-in-corn oil (W/O) emulsion droplets coated by polyglycerol polyricinoleate (PGPR). W/O emulsions (20 wt% aqueous phase, 80 wt% oil phase containing 8 wt% PGPR) were produced by high pressure homogenization (Emulsions 1), however, appreciable amount of relatively large water droplets (d>$10{\mu}m$) were found. To facilitate droplet disruption, viscosity of each phase was adjusted: (i) increased the viscosity of aqueous phase by adding 0.1 wt% xanthan (Emulsions 2); (ii) decreased the viscosity of oil phase and aqueous phase by heating them separately at $50^{\circ}C$ for 1 hr immediately before emulsification (Emulsions 3). Homogenizing at the elevated temperature clearly led to a smaller water droplet size, whereas xanthan neither improved nor adversely affected on the microstructures of the emulsions. In addition, the Emulsions 3 had good stability to droplet aggregation under shearing stress, thermal processing, and long term storage.

• Journal of Nutrition and Health
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• v.14 no.1
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• pp.34-40
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• 1981

This study was conducted to investigate the level of total serum cholesterol, triacylglycerol(TG), and phospholipid(PL) and the ratio of serum lipoprotein fractions of rats fed various types and amounts of fats for 12 weeks. Male weaning rats were fed one of four semipurified diets: control diet supplied 12% of calories as fat(polyunsaturated fatty acid:saturated fatty acid, 2 : 1), low fat diet supplied 3% of calories as fat(polyunsaturated fatty acid: saturated fatty acid, 2 : 1), 45%-corn oil diet supplied 45% calories from corn oil, and 45%-butter fat diet supplied 45% calories from butter fat. The level of total cholesterol in serum was increased in rats of 45%-butter fat diet group for the experimental period from 4 to 12 weeks, in rats fed 45%-corn oil diet from 8 to 12 weeks, but low fat diet group(3%-fat diet) is not different for all experimental period, compared with rats of control group(12%-fat diet). The level of TG in serum was also increased in rats fed 45%-butter fat diet for the entire experimental periods and in rats of low fat diet and 45%-corn oil diet groups at 12 weeks only, compared with control diet group. Specially TG in serum of rats fed low fat diet was remarkably increased at 12 weeks. After 12 weeks the level of PL in serum of rats fed low fat diet was lower than other diet groups. ${\alpha}$-Lipoprotein portion of lipoprotein fraction in serum was lower in rats fed 45%-butter fat diet at 4,8 and 12 weeks and rats fed low fat diet at 12 weeks, compared with control diet group and ${\beta}$-lipoprotein portion was reversely increased. Among them the ratio of lipoprotein fraction in rats fed low fat diet for 12 weeks was most significantly different.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.5
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• pp.655-660
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• 2003

Flavor components of dry shrimp, roasted-dry shrimp and roasted-dry shrimp with corn oil (w/w: 10%, 25%) were investigated to evaluate the effects of added corn oil on the formation of volatile components in dry shrimp during roasting process. The identified volatile included 20 nitrogen-containing compounds (7 pyrazines, 7 pyridines 3 pyrroles, others) 14 aldehydes, 5 alcohols, 4 ketones and 11 others. The largest quantities of lipid-derived products hexanal, nonanal, 2-pentylfuran, 1-octen-3-ol, trans-2-decenal, trans, cis-2,4-decadienal, trans, trans-2,4-decadienal were detected in the roasted-dry shrimp samples with corn oil. The lipid-derived aldehydes might be involved in the formation of 3- ethyl-2,5-dimethylpyrazine, 2,3,5-trimethyl-6- ethylpyrazine, 2-ethyl-5,6-dimethylpyrazine, 2,3,5- trimethylpyrazine, 3- ethyl-2,6-dimethylpyridine, 2-propylpyridine, ben-zopyrrole and the others. The nitrogen-containing compounds seem to be a major flavor component and responsible for characteristic flavor in roasted-dry shrimp with corn oil.

• Toxicological Research
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• v.31 no.3
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• pp.307-312
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• 2015

Trans fat is a unsaturated fatty acid with trans configuration and separated double bonds. Analytical methods have been introduced to analyze trans fat content in foods including infrared (IR) spectroscopy, gas chromatography (GC), Fourier transform-infrared (FT-IR) spectroscopy, reverses-phase silver ion high performance liquid chromatography, and silver nitrate thin layer chromatography. Currently, FT-IR spectroscopy and GC are mostly used methods. Trans fat content in 6 vegetable oils were analyzed and processing effects including baking, stir-frying, pan-frying, and frying on the formation of trans fat in corn oil was evaluated by GC. Among tested vegetable oils, corn oil has 0.25 g trans fat/100 g, whereas other oils including rapeseed, soybean, olive, perilla, and sesame oils did not have detectable amount of trans fat content. Among cooking methods, stir-frying increased trans fat in corn oil whereas baking, pan-frying, and frying procedures did not make changes in trans fat content compared to untreated corn oils. However, the trans fat content was so low and food label can be declared as '0' trans based on the regulation of Ministry of Food ad Drug Safety (MFDS) (< 2 g/100 g edible oil).

• Journal of Nutrition and Health
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• v.31 no.9
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• pp.1394-1403
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• 1998

The study was designed to observe the effect of dietary calcium and fats on plasma cholesterol level, hepatic microsomal fluidity and HMG-CoA reductase activity as well as the excretion of fecal bile acids and neutral sterols in 1, 2-dimethylhydrazine(DMH)-treated rats. Male Sprague Dawley rats, at 7 weeks of age, were divided into 2 groups, 0.3% and 1.0% Ca levels and each group again subdivided into 2 groups of corn oil and perilla oil. Each rat was intramuscularly infused with DMH for 6 weeks to give total dose of 180mg/kg body weight and also fed experimental diet containing 15%(w/w) different fit and Ca(0.3% or 1.0%) for 20 weeks. High dietary calcium(1.0%) did not significantly influence on plasma cholesterol as well as hepatic microsomal fluidity and HMG CoA reductase activity, but significantly reduced the excretion of total bile acid per gram of faces and increased the excretion of total neutral sterol. However, high dietary Ca reduced the excretion of secondary bile acid(deoxycholic and lithocholic acids) which was known as promoter for colon cancer. Perilla oil rich in n-3 ${\alpha}$-linolenic acid significantly decreased plasma cholesterol by increasing hepatic microsomal fluidity compared with corn oil, but did not influence on HMG CoA reductase activity. Perilla oil did not influence on fecal excretion of total and primary bile acids, but reduced the excretion of secondary bile acids. Therefore, it could be recommended to consume more fish product and food rich in calcium and use more perilla oil in meal preparation to prevent from coronary hear disease and colon cancer especially when high fit diet has been practiced. (Korean Nutrition 31(9) : 1394-1403, 1998)

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.211-216
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• 2004

Mono-and diacylglycerol-enriched oil was produced from corn oil through enzymatic glycerolysis using 1,3-specific immobilized lipase in solvent-free system and stirred-tank batch reactor. HPLC analysis revealed enriched oil was respectively composed of: 45.05, 16.27, 23.05, and 14.98% triacylglycerol, 1,3-diacylglycerol, 1,2-diacylglycerol, and monoacylglycerol; 13.21, 0.15, 2.02, 34.36, 49.12, and 1.14 mol% palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids; and 0.014, 0.029, 0.010 and 0.053% ${\alpha},\;{\gamma},\;{\delta}-$, and total tocopherols. Physiochemical and melting properties of enriched oil were evaluated. Oxidative stability study revealed enriched oil showed higher peroxide and p-anisidine values than corn oil. Rosemary extracts (100 to 300 ppm) reduce oxidation.

• Journal of the Korean Applied Science and Technology
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• v.3 no.2
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• pp.9-16
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• 1986

The purpose of this study was to find the effect of dietary polyunsaturated fat on of vitamin levels E, total cholesterol and HDL-cholesterol in serum of Spraque-Dawley male rats. Experimental rats were fed for 4 weeks with corn oil, perilla oil, lard at a level of 10% and 20% respectively. The results obtained are as follows; 1. Body weight gains were similar to all groups and food intake was significantly lower in all experimental diet groups than control diet group, especially 20% corn oil diet group was the lowest among the experimental diet groups. 2. Vitamin E levels in serum were significantly lower in 20% corn oil and 10%, 20% perilla oil diets groups than control diet group. 3. Serum total cholesterol levels were significantly higher in 20% perilla oil diet group which was significantly lower in vitamin E level than control diet group, and serum total cholesterol levels of 10%, 20% lard diets groups were significantly higher than control diet group. 4. Serum HDL-cholesterol levels were significantly lower in 20% perilla oil diet group which was significantly lower in vitamin E level than control diet group, and serum HDL-cholesterol levels of 10%, 20% lard diets groups also were significantly lower than control diet group.

• Journal of Nutrition and Health
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• v.10 no.3
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• pp.1-6
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• 1977

Flow properties of heated edible oils, such as soybean, rapeseed, rice bran, corn and perilla oils, were measured with Maron-Belner type capillary viscometer. These oils were heated at $180{\pm}5^{\circ}C$ (general cooking temperature) for $5{\sim}20$ hours except soybean oils ($5{\sim}40$ hours). Fluidities of these heated oils except rice bran oil were decreased according to heating time and decreasing ratio of fluidity was outstanding after 15 hour heating in corn oil and 20 hours heating in soybean and perilla oils. All the oils examined in this experiments except rice bran oil showed non-Newtonian motion after 15 hour hinting at high shear stress and Newtonian motion at less than 10 hour heating. In the soybean oil non-Newtonian flow property was outstanding after 30 hour heating at $180{\pm}5^{\circ}C$. Rice bran oil exhibit characteristic flow property, that is, non heated rice bran oil has lowest fluidity but heated one has highest fluidity compared to other oils examined in this experiment. Change of fluidity with extension of heating time was not detected and non heated rice bran oil showed non-Newtonian motion.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1993.10a
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• pp.344-352
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• 1993

The purpose of this study is to investigate the possibility of the non-destructive quality evaluation for food by the acoustic non-linear parameter B/A which is a measure of the non-linearity of the state equation of the medium in terms of pressure and density. The B/A of water, corn oil O/W(oil in water) emulsion and milk were measured by using a sound velocity measuring system. The B/A value of water was measured for ascertaining reliability of our experimental system. Corn oil W/W emulsion was prepared as a model of milk . It was proved that the B/A value of O/W emulsion was related to the oil concentration by a law of mixture. We applied this result to milk and obtained satisfactory results for predicting the milk fat concentration.