• Journal of Food Hygiene and Safety
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• v.9 no.4
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• pp.199-203
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• 1994

The oxidation of cholesterol in tallow heated at three frying temperatures, 130, 150 and 18$0^{\circ}C$ was studied by assaying cholesterol oxidation products(COP)by GC-MS. The correlation between levels of COP and changes of physicochemical parameters (peroxide value, polymer, polar components and dielectric constant) in tallow heated were studied. As temperature increased, the amount of cholesterol was decreased proportionally with heating time. However, the levels of COP did not increase considerably with increased frying temperature. The rate of cholesterol disappearance was the greatest at 18$0^{\circ}C$ and the smallest at 13$0^{\circ}C$. Larger amounts of COP formed were found at 15$0^{\circ}C$ than at 18$0^{\circ}C$. The levels of COP formed in tallow heated showed highly correlation with(r=0.94, n=30, p<0.01) polymer, polar components and dielectric constant, respectively.

• Food Industry And Nutrition
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• v.5 no.3
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• pp.66-73
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• 2000

• Proceedings of the Korean Society of Food Science and Nutrition Conference
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• 2000.06a
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• pp.17-17
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• 2000

• Food Science and Preservation
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• v.8 no.3
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• pp.338-344
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• 2001

The oxidative stability of cholesterol in tallow heated at different frying temperatures (130$\^{C}$, 150$\^{C}$, and 180$\^{C}$) was studied by identifying cholesterol oxides by thin layer chromatography(TLC). And fatty acid compositions in tallow heated were also measured and compared with cholesterol oxides. Unsaturated fatty acid contents slightly decreased as the heating time increased, whereas saturated fatty acid contents increased This phenomenon became excessive especially by heating to higher temperature. It was found that RF value and spot color of the nonsaponifiable lipids from tallow heated on TLC analysis accorded with the synthetic cholesterol oxides in this experiment. Four kinds of cholesterol oxides were detected in tallow heated for 24 hours at three different temperatures. The oxides were identified as 7-$\alpha$-hydroxycholesterol, 7-$\beta$-hydroxycholesterol, 7-ketocholesterol and cholesterol epoxide. It was found that there was a little difference in oxidative pattern of cholesterol between several heating temperatures.

• Nutrition Research and Practice
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• v.4 no.6
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• pp.462-469
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• 2010

Protamine has been widely used as a pharmaceutical product and natural food preservative. However, few studies have been conducted to assess the beneficial function of dietary protamine. This study examined the effects of dietary salmon protamine on serum and liver lipid levels and the expression levels of genes encoding proteins involved in lipid homeostasis in the liver of rats. Groups of male Wistar rats were fed AIN93G diet containing 2% or 5% protamine. After 4 weeks of feeding these diets, markedly decreased serum and liver cholesterol (CHOL) and triacylglycerol levels were noted. Increased activity of liver carnitine palmitoyltransferase-2 and acyl-CoA oxidase, which are key enzymes of fatty acid ${\beta}$-oxidation in the mitochondria and peroxisomes, was found in rats fed on protamine. Furthermore, rats fed protamine showed enhanced fecal excretion of CHOL and bile acid and increased liver mRNA expression levels of ATP-binding cassette (ABC) G5 and ABCG8, which form heterodimers and play a major role in the secretion of CHOL into bile. The decrease in triacylglycerol levels in protamine-fed rats was due to the enhancement of liver ${\beta}$-oxidation. Furthermore, rats fed protamine exhibited decreased CHOL levels through the suppression of CHOL and bile acid absorption and the enhancement of CHOL secretion into bile. These results suggest that dietary protamine has beneficial effects that may aid in the prevention of lifestyle-related diseases such as hyperlipidemia and atherosclerosis.

• Journal of the East Asian Society of Dietary Life
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• v.15 no.6
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• pp.759-765
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• 2005

This study was carried out to investigate the feeding effects of fermented wild grape by-product on pork meat qualities. The samples consisted of the pork not fed fermented wild grape byproduct(FWG-X) and the pork fed fermented wild grape byproduct(FWG-O). The moisture, crude protein, crude fat and crude ash were not significantly different between samples. The cholesterol and TBARS of FWG-O were lower than those of the FWG-X, and the salt soluble protein extractability of FWG-O was higher than that of the FWG-X(p<0.05). The calorie, cooking loss, water holding capacity, pH and volatile basic nitrogen were not significantly different between FWG-X and FWG-O. The meat colors of the a and b value of FWG-O were higher than those of the FWG-X, and in case of the fat color, the a value of FWG-O was higher than that of the FWG-X. The hardness, springiness, cohesiveness, gumminess, chewiness and shear force were not significantly different between FWG-X and FWG-O. The total amino acid contents of FWG-X and FWG-O were 74.35 and 69.59g/100g protein, respectively, The raw meat color of FWG-O was higher than that of the FWG(p<0.01), and the cooked meat color(p<0.05), taste(p<0.001), flavor(p<0.001), juiciness(p<0.01) and palatability(p<0.01) were superior to those of the FWG-X. This study showed that fermented wild grape by-product decreased the cholesterol content and lipid oxidation with enhancing the sensory score.

• Korean Journal of Plant Resources
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• v.28 no.2
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• pp.168-177
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• 2015

Here we study the anti-obesity effects of by-product from soybean on mouse fed high fat diet. The body weight gain, visceral and subcutaneous adipose tissue weight, liver and epididymal adipose tissue weight in freeze-dried soybean-soaking-water (SSW) powder fed group showed lower level than those in high fat diet (HFD) group by determining with weight measuring and histological methods. Also, histological analyses of the liver and fat tissues of SSW grouped mice revealed significantly less number of lipid droplets formation and smaller size of adipocytes compared to the HFD group. Moreover, the levels of total serum cholesterol, LDL-cholesterol and the atherogenic index were decreased in the SSW groups. Especially, in SSW group, the levels of phosphorylation of two lipid oxidation enzymes, adenosine monophosphate-activated protein kinase (AMPK) and acetyl-CoA carboxylasse (ACC) were elevated hence that may activate fatty acid oxidation. But AST and ALT levels were not changed in blood. By micro-CT analysis of abdomen, SSW groups significantly showed a tendency to decrease visceral and subcutaneous fats as well as fat-deposited areas compared to HFD group. Taken together, we suggest that soybean soaking water has a function in ameliorating obesity through inhibiting lipid synthesis as well as stimulating fatty acid oxidation.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.7
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• pp.1191-1201
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• 2020

Objective: The aim of this study was to evaluate the chemical-nutritional parameters, oxidative stability and volatile profile of eggs and cakes made with eggs from laying hens fed with a dietary supplementation of extruded linseed. Methods: Two thousand ISA Warren laying hens were randomly divided into two groups: a control group was fed with a standard diet while the experimental group received the same diet supplemented with 7% of extruded linseed. The trial lasted 84 days, in which three samplings of laid eggs were performed. Samples of eggs and food systems arising from eggs were then analyzed in order to obtain information about β-carotene and total flavonoid content, antioxidant activity, fatty acid profile, lipid oxidation, and volatile profile. Results: Linseed induced the increase of α-linolenic acid with consequent reduction of the ω-6/ω-3 ratio (4.3:1 in egg yolk); in addition to this, was evidenced the cholesterol reduction and the significant increase in total flavonoids and β-carotene, although no variations were detected in antioxidant capacity. Even in cooked products there was not only a direct effect of linseed in increasing α-linolenic acid, but also in inducing the reduction of cholesterol and its major oxidation product, 7-ketocholesterol. The dietary linseed integration was also shown to affect the volatile profile of baked products. Conclusion: Data confirmed that dietary supplementation with extruded linseed resulted in food products with interesting implications for human health. With regard to the volatile profile of baked products it would be necessary undertake further sensorial analysis in order to evaluate any variations on flavor and consumer acceptability.