• Korean journal of food and cookery science
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• v.22 no.3 s.93
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• pp.299-306
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• 2006

The numerous varieties of coffee beans contain a wide range prices and qualities. While the varieties of green coffee beans can generally be distinguished by their appearance, this visual criterion is impossible after the roasting process. Therefore, we need to develop a classification method or device. In this study, the potential of a new type of electronic nose, fast gas chromatography based on a surface acoustic wave sensor(SAW), was evaluated for the classification of origins and blended commercial brands in roasted coffee beans. Eight blended commercial brands and the origins of four similarly roasted ground coffee beans(with no significant difference of color) were rapidly(90 sec/sample) classified. The reproductive results were easily understandable over the aroma image pattern by $VaporPrint^{TM}$. In conclusion, GC-SAW electronic nose can be applied to the classification of origins and commercial brands in roasted ground coffee beans and to e evaluation of the similarities and differences of volatile pattern between samples.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.839-847
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• 2007

The aims of this study were twofold: i) to investigate changes in the sensory characteristics and consumer preference of diluted espresso drinks according to different dilution rates; ii) to compare the physicochemical characteristics between diluted espresso coffees, using the preferred coffee of this study and commercial products from coffee shop chains. Descriptive analysis using a 15 cm line scale, and a consumer preference test were carried out by 6 trained panelist,; and 50 consumers (F=39, M=11), respectively. Appearance (transparent, black), odor (bitter, rich), taste (bitter, burnt, astringent, umami, sour), and mouth-feel (aftertaste, body, coarseness, oily, roughness, soft-swallowing) were significantly different among the 3-, 5-, 7-, 9-, and 11-times dilution rates. In particular, the sensory characteristics associated with mouth-feel showed obvious differences with the dilution rates. In the consumer preference test, the 9-times diluted espresso had the highest preference, whereas the 3-times diluted espresso showed the lowest preference. Moreover, the 9-times diluted espresso demonstrated similar physicochemical characteristics such as pH, sugar content, and total solid content to those of the commercial diluted espresso drinks from coffee shop chains. In conclusion, the sensory characteristics and consumer preference of the diluted espressos were influenced by the dilution rates.

• Food Science of Animal Resources
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• v.31 no.6
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• pp.827-833
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• 2011

The objective of this study was to develop a fluorogenic real-time PCR-based assay for detecting and quantifying amounts of cow milk in cow/goat milk mixtures or goat milk products. In order to quantify the exact amount of cow milk in cow/goat raw milk mixtures and commercial goat milk products, it was necessary to achieve quantitative extraction of total genomic DNA from the raw milk matrix. Both mammalian-specific PCR and cow-specific PCR were performed. A cow-specific 252 bp band obtained from the raw cow milk and raw goat milk mixtures, commercial goat milk, and two goat milk powders was identified, along with the relationship between the cow milk amount and band intensity of the electrophoresis image. The detection threshold was found to be 0.1%. The expression of cow's 12S rRNA in the cow/goat milk mixtures, commercial goat milk, and two goat milk powders was identified. The expression quantity of the milk 12S rRNA increased with increasing ratios of the cow/goat milk mixtures. Using these calibrated relative expression levels as a standard curve in the cow/goat raw milk mixtures, the contents of cow milk were 1.8% in the commercial goat milk, 9.6% in goat milk powder A, and 11.6% in goat milk powder C. However, cow milk was not detected in goat milk powder B.

• Journal of Food Hygiene and Safety
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• v.24 no.2
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• pp.124-127
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• 2009

The aim of this study is to evaluate the estrogenic activity of Cucurbita pepo seed extract which includes ${\beta}-sitosterol$ and other phytosterols. Sample was extracted from Cucurbita pepo seed by supercritical carbondioxide method and resuspended with ethanol. Estrogenic activity was measured by recombinant yeast assay which detects estrogenic activity using recombinant yeast with high level of estrogenic receptor. However, estrogenic activity of pumpkin seed extract was not found in this study. Based on this data, pumpkin seed extract will not cause estrogenic disturbance.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.1
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• pp.1-8
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• 2012

We compared the dietary behaviors and living habits of Han Children living in both China and Korea to find any influences from the different living environments. Three hundred $5^{th}$ and $6^{th}$ -grade children in China and two hundred thirty three $5^{th}$ and $6^{th}$ -grade children in a Chinese school in Korea were surveyed via questionnaire. Mean BMI was higher and sleeping hours were lower in the children living in Korea compared to the children living in China. Mean age and education level of the parents were higher in the children living in Korea. Most of the dietary behaviors discovered via the questionnaire showed similar tendencies in the two groups. However, in terms of skipping breakfast, deviating in food habits, snacking before sleeping, and snacking right after eating a meal, the children living in Korea showed significantly higher frequencies. Also, children living in Korea showed significantly lower frequencies of overeating, snacking while watching TV or using the computer, and eating food when stressed, than children living in China. In living habits, children living in Korea do less regular exercise and use buses or cars more frequently for short distance transportation and spend more time to watch TV or computer than the children living in China. Therefore, it seems that different living environments may somewhat influence the dietary behaviors and living habits of children even if they have the same ethnic background.

• Korean Journal of Human Ecology
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• v.16 no.1
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• pp.183-191
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• 2007

The purpose of this study was to measure the effect of nausea and learned food aversion on relationships linking food neophobia to appetite and food rejection. A total of 250 questionnaires were completed. Path analytic model was used measure the effect of mediator. Results of the study demonstrated that the path analytic result for the data also indicated excellent model fit. The influences of food neophobia on nausea and food rejection were statistically significant. The influences of nausea on learned food aversion and appetite were statistically significant. The influences of food neophobia on learned food aversion and appetite were not statistically significant. The influence of nausea on food rejection was not statistically significant. Moreover, nausea and aversion played a perfectly mediating roles in the relationship between food neophobia and appetite. Aversion also played no mediating role in the relationship between food neophobia and food rejection.

• Preventive Nutrition and Food Science
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• v.14 no.1
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• pp.37-42
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• 2009

The protective activity of seolitae chungkukjang added with green tea against oxidative stress was investigated under the cellular systems using LLC-$PK_1$ cells. The treatment of 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) showed increase in lipid peroxidation, and decrease in endogenous antioxidant enzymes activity and cell viability. However, the methanol extract of seolitae chungkukjang inhibited lipid peroxidation by 58.3%, and increased cell viability up to more than 60%. In addition, it enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Seolitae chungkukjang improved oxidative stress-induced cellular injury through the radical scavenging activities. In particular, the addition of green tea in seolitae chungkukjang showed stronger effect against oxidative stress induced by AAPH. The more addition of green tea resulted in the greater antioxidative effect through elevation in activities of SOD and GSH-Px, and inhibition of lipid peroxidation, eventually leading to increase in cell viability. Theses results suggested that seolitae chungkukjang added with green tea have protective effects from cellular oxidative damage and could be considered as an application for the development of chungkukjang with functionality.

• Journal of Microbiology and Biotechnology
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• v.26 no.7
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• pp.1206-1215
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• 2016

Ginsenosides are the major active ingredients in ginseng used for human therapeutic plant medicines. One of the most well-known probiotic bacteria among the various strains on the functional food market is Lactobacillus rhamnosus GG. Biocatalytic methods using probiotic enzymes for producing deglycosylated ginsenosides such as Rd have a growing significance in the functional food industry. The addition of 2% cellobiose (w/v) to glucose-free de Man-Rogosa-Sharpe broths notably induced β-glucosidase production from L. rhamnosus GG. Enzyme production and activity were optimized at a pH, temperature, and cellobiose concentration of 6.0, 40℃, and 2% (w/v), respectively. Under these controlled conditions, β-glucosidase production in L. rhamnosus GG was enhanced by 25-fold. Additionally, whole-cell homogenates showed the highest β-glucosidase activity when compared with disrupted cell suspensions; the cell disruption step significantly decreased the β-glucosidase activity. Based on the optimized enzyme conditions, whole-cell L. rhamnosus GG was successfully used to convert ginsenoside Rb1 into Rd.

• Korean journal of food and cookery science
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• v.29 no.3
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• pp.275-281
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• 2013

This study was performed to evaluate the quality characteristics and antioxidative activities of cookies prepared with different amounts of purple sweet potato powder. Moisture and crude ash contents were lowest in the control group followed in order by the 10%, 20%, and 30% purple sweet potato powder addition groups. The lightness and yellowness values measured by Hunter color system decreased based on the amount of purple sweet potato powder concentration added to cookies. The total phenolic compound and anthocyanin contents were the highest in 30% purple sweet potato powder added cookies. The DPPH radical scavenging activity of 30% purple sweet potato powder added cookies showed the highest values among groups. In the sensory evaluation, the scores for taste, texture and overall preference were significantly highest in cookies with 10% and 20% purple sweet potato powder. Considering the scores of antioxidant activity and sensory evaluation, the concentration of between 10% and 20% addition of purple sweet potato powder would be ideal for development of functional cookies.

• Food Science and Biotechnology
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• v.16 no.2
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• pp.228-233
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• 2007

This study evaluated the effects of carnitine supplementation on obesity caused by a high-fat diet in C57BL/6J mice. The mice were fed a normal diet (ND), high-fat diet (HD), or carnitine-supplemented (0.5% of diet) high-fat diet (HDC) for 12 weeks. The results showed that body weight, energy intake, and feed intake were lower in the HDC group than the control groups. Acid-soluble acylcarnitine (A SAC), acid-insoluble acylcarnitine (AIAC), and total carnitine (TCNE) in the serum and liver were significantly higher in the HDC group. Hepatic carnitine palmitoyl transferase-I activity was significantly higher in the HDC group than the control groups. Acyl-coA synthetase (ACS) and carnitine palmitoyl transferase-I (CPT-I) mRNA expression in the liver was highest in the HDC group, however hepatic acetyl-coA carboxylase (ACC) mRNA expression in this group was lowest. Serum leptin levels and abdominal fat weight were lowest in the HDC group. We concluded that L-carnitine supplementation diminished the risk of obesity caused by a high-fat diet.