• YAKHAK HOEJI
• /
• v.34 no.4
• /
• pp.282-286
• /
• 1990

An hydrocarbon alcohol and steroids were isolated from the hexane fraction of the extract from the seeds of Phaseolus radiatus L. And also a flavonoid was identified from the ethyl acetate and butanol fraction. The structure of the obtained compound were elucidated by spectroscopic methods (UV, IR, mass and NMR) and their physicochemical properties. As the results, triacontanol, stigmasterol, ${\beta}-sitosterol$ and vitexin were identified.

• The Korean Journal of Food And Nutrition
• /
• v.10 no.2
• /
• pp.254-262
• /
• 1997

new wild grape(NWG) cultivated in north Kyungki province in Korea, was tested by analyzing the proximate and physicochemical components of fresh fruit, the chemical components and sensory evaluation of wines made from the grape. NWG contained about 10% seed, and about 70% of juice. Total sugar content, total acidity and pH of the fruit juice were 17.50, 1.14 and 3.48%, respectively. Tartaric acid and malic acid contents of the NWG juice were 0.396 and 0.509%, respectively. Ethanol fermentation of the NWG by Saccharomyces cerevisiae Montrachet was rapid. The ethanol content, total acidity and pH of pink wine made from the NWG juice showed 11.88, 0.85 and 3.55%, respectively. Tartaric acid and malic acid contents of pink wine were 0.208 and 0.421%, respectively. Total anthocyanin content(A520) and color intensity(A520+A420) of pink wine were 5.46 and 9.39, showing greatly higher total anthocyanin content and color intensity than those of European red wines. Total phenol contents of NWG wine were 2, 300~3, 800mg/$\ell$. The pink wine made from the fruit juice was better than the red wine in their quality parameters and sensory scores.

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

• Journal of Ginseng Research
• /
• v.9 no.2
• /
• pp.170-178
• /
• 1985

Korean red ginseng tails was extracted with solutions having various ethanol concentration at the temperature range of 70-100 $^{\circ}C$. Extraction was carried out for 1-5 times of 8 hours at given temperature. The results obtained on physicochemical properties of yields, saponins, sugars, minerals, color and viscosity were analyzed statistically to find the correlation with extracting conditions. A very high positive correlation was found between extraction time and cumulative values of yields of chemical components. Increase in ethanol concentration affected negatively on viscosity, absorbencies and yields of soluble solids and minerals. Some of the properties also showed a high correlation with temperature increase. Equations were also derived from the significant results on correlation analysis.

• Bulletin of the Korean Chemical Society
• /
• v.8 no.3
• /
• pp.158-161
• /
• 1987

A Series of hydrophilic-hydrophobic copolymeric surfaces of 2-hydroxyethyl methacrylate (HEMA) and various alkyl methacrylate (RMA) have been prepared by in-situ solution copolymerization using a redox radical initiator. Contact angles of various probing fluids on the polymeric surfaces were determined in air (hydrophobic environment) and under water (hydrophilic environment). From contact angle data, the dispersive interaction contribution (${\gamma}^d_s$) and the polar contribution (${\gamma}^p_s$) to the total surface free energy (${\gamma}^d_s$) and interfacial energetic quantities (e.g., water-polymer, liquid-polymer interface, etc.) were estimated by surface and interface physicochemical theory. From the comparison of surface energetic components between hydrophobic and hydrophilic media, it is found that surface and interface energetic components of polymeric surface as a representative low-energy surface are highly dependent on environmental fluids. Also, from the correlation between interfacial energetic results and surface energetic criterion of biocompatibility, we found that HEMA/BMA, HEMA/HMA copolymer systems are in the region of biocompatibility.

• Food Science and Preservation
• /
• v.11 no.3
• /
• pp.347-351
• /
• 2004

Physicochemical properties such as proximate components, minerals, amino acids, organic acid and free sugars of Pleurotus eryngii were investigated. Among the proximate components of Pleurotus eryngii contents of crude protein and total sugar were higher than that of others. The contents of magnesium and sodium were higher than that of other minerals. Hypoproline content was the highest in free amino acid. Among the amino acid, the contents of arginine, lycine, glutamic acid and phenylalanine were 509.03, 410.53, 190.05 and 150.63 mg$\%$, respectively. Organic acids such as citric acid, oxalic acid, formic acid and malic acid were analyzed, contents of citric acid and lactic acid were higher than that of others. Among the free sugars, the content of glucose was the highest, followed by fructose, ribose, galactose, lactose, arabinose and maltose.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.6
• /
• pp.1027-1033
• /
• 1998

Stewed pumpkin juice(SPJ) has recently become popular as a health drink, and its consumption is growing rapidly. Well ripened pumpkin was heated in a pressure cooker and squeezed to an extract and then packed in retort pouches. The ingredient of ginger, onion, jujube and boxthorn was added to samples of SPJ in order to observe the effect on the composition of SPJ during production and storage at 28oC for 60 days. The level of the main mineral(K) in pumpkin varied when the ingredients were added. The pH of control SPJ showed more changes than the SPJs with ingredients added, and there was almost no change in the samples with boxthorn. During storage, titrable acidity decreased in all samples, and the SPJs with ginger and jujube showed relatively little change compared to the samples of control SPJ and SPJ with onion. As for soluble solid and reducting sugar, the SPJs with jujube and boxthorn showed the highest reading. For carotenoid, the SPJs with jujube, ginger, boxthorn and onion listed according to the amount of carotenoid contained more total carotenoid than the control SPJ. Most of the carotenoid in pumpkin and its extract was found to be carotene by HPLC and Chandler's method. Sensory evaluation of the SPJ samples with ingredients revealed preference for the taste of the SPJs with jujube, ginger and boxthorn in declining order of preference. The taste of SPJs with ingredients added was generally preferent over the control SPJ except the case of SPJ with onion.

• Journal of Korean Society for Atmospheric Environment
• /
• v.27 no.2
• /
• pp.168-180
• /
• 2011

The variation of the physicochemical properties of atmospheric aerosols in coexistence of the heavy Asian Dust and Haze observed from $15^{th}$ to $17^{th}$ March 2009 in Seoul was scrutinized through the mass and ion concentration observations and synoptic weather analysis. Although the ratio of PM1.0/PM10 was constant at 0.3 (which is typical during Asian Dust period in Korea) during the measurement period, both PM10 and PM1.0 mass concentrations were 3~6 times and 2~4 times higher than that of clear days, respectively. Water-soluble ion components accounted for 30~50% of PM10 and 50~70% of PM1.0 mass concentration. One of the secondary pollutants, $NO_3^-$ was found to be associated with $Ca^{2+}$ and $Na^+$ in coarse mode indicating that the aerosol derived from natural source was affected by anthropogenic pollutants. While the acidity of the aerosols increased in fine mode when the stagnation of weather patterns was the strongest (March $16^{th}$), the alkalinity increased in coarse mode when new air masses arrived with a southwestern wind after ending a period of stagnation (March $17^{th}$). In the selected case, SOR (Sulfur Oxidation Ratio, $nSO_4^{2-}/[nSO_4^{2-}+nSO_2]$) and NOR (Nitrogen Oxidation Ratio, $nNO_3^-/[nNO_3^-+nNO_2]$) values of ion components were higher than the general values during Asian Dust period. These results imply that dust aerosols could be mixed with pollutants transported from China even in heavy Asian Dust cases in Korea.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.295-295
• /
• 2017

Rice (Oryza sativa L.) is one of the most important food crops in the world. The eating quality of cooked rice is the most important trait japonica rice breeding in Korea. Rice varieties that produce kernels that are firm and fluffy after cooking are generally favored in countries such as India, Pakistan, and Indonesia. Whereas varieties with kernels that maintain its shape, glossiness, savory odor, stickiness, and tenderness when cooked are preferred in Korea. This study analyzed the major physicochemical components of rice grain associated with the eating quality of 20 japonica rice varieties. Physicochemical components such as the amylose content, protein content, amylographic characteristics of polished rice, and texture of cooked rice were tested using a Tensipresser as alternative indirect methods in determining rice eating quality. Evaluation of eating quality of cooked rice using sensory test was conducted with 20 well trained members. The 20 rice varieties in different eating quality showed amylose contents of 17~20%. The amylose content of rice varieties had negative correlation with peak viscosity, however positive correlation with setback viscosity was observed. The stickiness and adhesiveness of cooked rice showed correlation with the amylose content and amylopectin chain length distribution. Rice varieties with good eating quality showed less retrogradation of cooked rice and higher hot viscosity of rice flour in amylogram.

• Food Science of Animal Resources
• /
• v.34 no.3
• /
• pp.287-296
• /
• 2014

The physicochemical and functional traits for loin muscles of Hanwoo steers were compared by quality grade (QG). A total of 500 Hanwoo steers were slaughtered, their carcasses were categorized into four groups (QG 1++, 1+, 1, and 2), and the longissimus dorsi muscles were analyzed. QG 1++ group had the highest fat and lowest moisture content (p<0.05). QG 1++ showed higher $L^*$ and $b^*$ color values, higher cooking loss, and lower shear force values, compared with the other groups (p<0.05). The flavor, tenderness, juiciness, and preference scores by sensory evaluation were highly ranked for premium QG groups (1++ and 1+). Regarding the micro compounds, QG 1 and QG 2 had greater amounts of inosine monophosphate, and QG 2 had greater amounts of anserine, carnosine, and creatine, than QG 1++ (p<0.05). QG 1++ and 1+ had higher percentages of oleic acid (C18:1) than QG 2 (p<0.05). Within premium QG 1++ and 1+, the results of the nucleotides, free amino acids, dipeptides, and fatty acids did not show any distinctive differences. Hanwoo beef as determined by the current grading system was not significantly different in terms of functional components; the only significant difference was in intramuscular fat content.