• KOREAN JOURNAL OF CROP SCIENCE
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• v.47
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• pp.15-32
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• 2002

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s-1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great progress and success was obtained in development of high-quality japonica cultivars and quality evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice cultivars and special rices adaptable for food processing such as large kernel, chalky endosperm, aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer, Recently, new special rices such as extremely low-amylose dull or opaque non-glutinous endosperm mutants were developed. Also, a high-lysine rice variety was developed for higher nutritional utility. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and texture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak, hot paste and consistency viscosities of viscosities with year difference. The high-quality rice variety "IIpumbyeo" showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic microscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high probability of determination. The $\alpha$-amylose-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were IIpumbyeo, Chucheongyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tonsil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice breed. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large grain rices showed better suitability far fermentation and brewing. The glutinous rice were classified into nine different varietal groups based on various physicochemical and structural characteristics of endosperm. There was some close associations among these grain properties and large varietal difference in suitability to various traditional food processing. Our breeding efforts on improvement of rice quality for high palatability and processing utility or value-adding products in the future should focus on not only continuous enhancement of marketing and eating qualities but also the diversification in morphological, physicochemical and nutritional characteristics of rice grain suitable for processing various value-added rice foods.ice foods.

• Journal of the Korean Applied Science and Technology
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• v.34 no.2
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• pp.244-253
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• 2017

The aim of this study was to investigate the bioactivity and antioxidant activity of peel from Gardenia jasminoides Ellis fructus (GJE). We were separated into GJE peel. After that, we determined anthocyanin. GJE peel were extracted by 70% methanol, distilled water (DW) and ethyl acetate (EA) three solvents. To investigate by the solvent extract of total phenol content and value as a functional food ingredient of GJE peel through nitrogen oxide scavenging activity, antioxidant activity, reducing power and lipid peroxidation inhibition were performed. Solvent extract bioactivity of increasing concentrations (0.2, 0.4, 0.6 mg/mL) were significantly increased (p<0.05). GJE peel extracts showed lower activity than positive control (ascorbic acid, BHA, trolox). The total phenol contents of GJE peel extracts were highest in EA extract. However, the order of total phenol content of the solvent in the GJE peel and the results of analysis of various physiological activities were inconsistent. Considering the extraction yield and various physiological activities, it is expected to be effective when extracted from 70% methanol and DW extract. The results suggest that GJE peel is highly expected to be useful as a functional foods and natural antioxidant.

• Food Science of Animal Resources
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• v.33 no.5
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• pp.626-632
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• 2013

This study was performed to determine the antioxidant activity of the oven-dried paprika powder as affected by the color differences of paprika and to evaluate physicochemical characteristics and antioxidant activity of pork patties with various levels of paprika powders. The total phenolic contents of the paprika were not affected by color and solvent (p>0.05). The methanol extracted paprika powder showed higher DPPH radical scavenging activity than water extracted counterpart, and no differences were observed at concentration of 0.5% as compared to the reference (ascorbic acid) (p>0.05). In all treatments, the iron chelating ability increased with increasing concentrations. At a concentration of 1.0%, methanol extracts of orange paprika (MOP) and water extracts of red paprika (WRP) were not different from the reference, (ethylendiaminetetraacetic acid, EDTA). The paprika color and extraction solvent didn't affect reducing power of paprika powder at each concentration (p>0.05). Pork patties with red paprika powder were higher redness values than those with orange ones, regardless of addition level. The addition of red paprika increased the yellowness, and patties with 1.0% orange paprika powder showed the highest value. TBARS values were decreased with increasing paprika powder, especially, patties with 1.0% paprika powder were lower TBARS than those with 0.5% paprika powder, resulting in similar to those with ascorbic acid (p>0.05). Although the microbial counts increased with storage time, paprika powders did not inhibit microorganisms during storage. In conclusion, paprika powders could be used as a natural antioxidant in meat products, regardless of paprika color.

• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.12-18
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• 1983

Changes in the quality and amino acid composition of soymilk prepared from soaked and germinated soybeans were investigated. Soybeans were soaked in water for 3 hrs and germinated at $18{\pm}1^{\circ}C$ for 5 days followed by water extraction at room temperature, and then the soymilk was boiled for 30 min. The initial yields of total solid and protein after soaking were 80.7% and 88.6%, respectively and decreased slowly during germination. A slow decrease in lipids and a rapid reduction in total sugar content were found during germination. The change in protein fraction content of soymilk showed an initial increase followed by a gradual decrease. The intrinsic viscosity increased rapidly after 3 days of germination to maximum value at 4th day, then decreased. The amino acid composition of protein fraction of soymilk showed little change while that of nonprotein fraction changed significantly. After 4 days of germination, aspartic acid and alanine increased more than twice, and methionine and tyrosine decreased to half of their initial composition in soymilk prepared from soaked soybean.

• Microbiology and Biotechnology Letters
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• v.44 no.4
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• pp.452-460
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• 2016

This study was designed to develop a functional pharma-food using Salicornia europaea (SE). Tiny seeds from the mature SE were collected, and their biological activities were evaluated. The extraction yield of the seed in hot water was found to be 29.6% and the hot water extract (HWE) contained 25.7 mg/g total polyphenol (TP) and 11.5 mg/g total flavonoid (TF), which are similar to those contained in leaf and stem of SE. Among the subsequent organic solvent fractions, the ethylacetate (EA) fraction exhibited the highest content of TP (158.3 mg/g), TF (136.2 mg/g), and total sugar (228.3 mg/g). The EA fraction exhibited broad-range antibacterial activities against gram-positive bacteria, and the butanol fraction exhibited growth inhibitory effect against only Staphylococcus epidermidis. An antioxidation activity assay of the HWE and its fractions showed the EA fraction to have the highest radical scavenging activity with $RC_{50}$ values of 57.0, 29.0, and $28.9{\mu}g/ml$ against DPPH anion, ABTS cation, and nitrite, respectively. The $RC_{50}$ values of vitamin C against DPPH anion, ABTS cation, and nitrite were 10.7, 4.0, and $18.0{\mu}g/ml$, respectively, indicating that the EA fraction of SE has potent antioxidant compounds. In an anticoagulation assay, the EA fraction exhibited a 15-fold extended thrombin time at 5 mg/ml and activated partial thromboplastin time at 7 mg/ml, which are comparable to the activities of aspirin. The HWE and its fractions had no hemolysis activities against human RBCs at up to 1 mg/ml. These results suggest that the EA fraction from SE has a great potential as a new antibacterial and anticoagulation agent.

• Journal of Korea Water Resources Association
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• v.47 no.4
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• pp.371-384
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• 2014

This study developed a new algorithm of extreme rainfall extraction based on the Communication, Ocean and Meteorological Satellite (COMS) and the Tropical Rainfall Measurement Mission (TRMM) Satellite image data and evaluated its applicability for the heavy rainfall event in July-2011 in Seoul, South Korea. The power-series-regression-based Z-R relationship was employed for taking into account for empirical relationships between TRMM/PR, TRMM/VIRS, COMS, and Automatic Weather System(AWS) at each elevation. The estimated Z-R relationship ($Z=303R^{0.72}$) agreed well with observation from AWS (correlation coefficient=0.57). The estimated 10-minute rainfall intensities from the COMS satellite using the Z-R relationship generated underestimated rainfall intensities. For a small rainfall event the Z-R relationship tended to overestimated rainfall intensities. However, the overall patterns of estimated rainfall were very comparable with the observed data. The correlation coefficients and the Root Mean Square Error (RMSE) of 10-minute rainfall series from COMS and AWS gave 0.517, and 3.146, respectively. In addition, the averaged error value of the spatial correlation matrix ranged from -0.530 to -0.228, indicating negative correlation. To reduce the error by extreme rainfall estimation using satellite datasets it is required to take into more extreme factors and improve the algorithm through further study. This study showed the potential utility of multi-geostationary satellite data for building up sub-daily rainfall and establishing the real-time flood alert system in ungauged watersheds.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.46-55
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• 2017

In this study, extracts of gamma-irradiated Aralia continentalis for health and beauty food resources were examined on antioxidant activities and increasing extraction yield. In photostimulated luminescence analysis, non-irradiated (0 kGy) sample showed an intermediate result of 891.00 photon counts (PCs), whereas irradiated (5 and 10 kGy) samples showed positive results of 79,956.67 and 282,498.67 PCs, respectively. The thermoluminescence ratio of non-irradiated samples was 0.018, whereas the values of irradiated samples (5 and 10 kGy) were 0.395 and 0.464, respectively. Electron spin resonance (ESR) analysis as a physical technique for irradiation identification of Aralia continentalis showed a pair of peaks on a space of 6.0 mT in the symmetric ESR spectrums. For phenolics of gamma-irradiated Aralia continentalis, water extracts had the highest amounts of 7.61 mg/g at non-irradiated condition (0 kGy) while 50% ethanol extracts had the highest amounts of 6.86 mg/g at 10 kGy irradiation. 2,2-Diphenyl-1-picrylhydrazyl scavenging activity of water and 50% ethanol extracts from non-irradiated and irradiated Aralia continentalis were very high (94.99~100.00%). 2,2'-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation inhibitory activity was over 95.00% at $200{\mu}g/mL$ phenolics. Antioxidant protection factor (PF) showed a very high level of activity (1.38~2.51 PF). Thiobarbituric acid reactive substance inhibitory activity was high (70% and 95%, respectively). Thus, treatment of gamma irradiation can be used as a method of storage for long-term preservation of Oriental medicine.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.4
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• pp.260-266
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• 2008

Small lysimeter experiment under rain shelter plastic film house was conducted to investigate the effect of soil characteristics on the leaching and soil solution concentration of nitrate and phosphate. Three soils were obtained from different agricultural sites of Korea: Soil A (mesic family of Typic Dystrudepts), Soil B (mixed, mesic family of Typic Udifluvents), and Soil C (artificially disturbed soils under greenhouse). Organic-C contents were in the order of Soil C ($32.4g\;kg^{-1}$) > Soil B ($15.0g\;kg^{-1}$) > Soil A ($8.1g\;kg^{-1}$). Inorganic-N concentration also differed significantly among soils, decreasing in the order of Soil B > Soil C > Soil A. Degree of P saturation (DPS) of Soil C was 178%, about three and fifteen times of Soil B (38%) and Soil A (6%). Prior to treatment, soils in lysimeters (dia. 300 mm, soil length 450 mm) were tabilized by repeated drying and wetting procedures for two weeks. After urea at $150kg\;N\;ha^{-1}$ and $KH_2PO_4$ at $100kg\;P_2O_5\;ha^{-1}$ were applied on the surface of each soil, total volume of irrigation was 213 mm at seven occasions for 65 days. At 13, 25, 35, 37, and 65 days after treatment, soil solution was sampled using rhizosampler at 10, 20, and 30 cm depth and leachate was sampled by free drain out of lysimeter. The volume of leachate was the highest in Soil C, and followed by the order of Soils A and B, whereas the amount of leached nitrate had a reverse trend, i.e. Soil B > Soil A > Soil C. Soil A and B had a significant increase of the nitrate concentration of soil solution at depth of 10 cm after urea-N treatment, but Soil C did not. High nitrate mobility of Soil B, compared to other soils, is presumably due to relatively high clay content, which could induce high extraction of nitrate of soil matrix by anion exclusion effect and slow rate of water flow. Contrary to Soil B, high organic matter content of Soil C could be responsible for its low mobility of nitrate, inducing preferential flow by water-repellency and rapid immobilization of nitrate by a microbial community. Leached phosphate was detected in Soil C only, and continuously increased with increasing amount of leachate. The phosphate concentration of soil solution in Soil B was much lower than in Soil C, and Soil A was below detection limit ($0.01mg\;L^{-1}$), overall similar to the order of degree of P saturation of soils. Phosphate mobility, therefore, could be largely influenced by degree of P saturation of soils but connect with apparent leaching loss only more than any threshold of P accumulation.

• Journal of Food Hygiene and Safety
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• v.26 no.4
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• pp.315-321
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• 2011

This study was performed to investigate contamination levels of aflatoxins, the secondary metabolites produced by fungi Aspergillus flavus and A. parasiticus, in herbal medicine. Herbs is susceptible to these fungi infections through its growth harvest, transport and storage. This study determine the aflatoxin $B_1$, $B_2$, $G_1$ and $G_2$ levels by HPLC-florescence detector coupled with photochemical enhancement in 558 samples herbal medicine distributed in Korea and China. Also, We checked a transfer ratio of aflatoxins from raw herbal medicines to herbal medicine extract. Hot water extraction of herbal medicines was prepared by air pressure and high pressure condition. The analytical method for aflatoxins was validated in this method. In results recoveries of the analytical method were ranged from 67.4% to 96.2% and, limits of detection and quantitation for aflatoxins were $0.015{\sim}0.138\;{\mu}g/kg$ and $0.046{\sim}0.418\;{\mu}g/kg$, respectively. According to the results of monitoring on aflatoxins in herbal medicine, aflatoxins 1.7 ug/kg $B_1$ and 0.9 ug/kg $G_1$ were detected in only one sample of Strychni Ignatii Semen, and 0.8 ug/kg $G_1$ in Strychni Semen. About 13.6~51.3% of aflatoxins were transferred to hot water extract. Although the detected levels are under the permitted levels for aflatoxins in herbal medicine, these amounts should be considered in regard to overall daily exposure to mycotoxins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.3
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• pp.411-418
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• 2014

Three mushroom mycelia, Ganoderma lucidum, Hericium erinaceum, and Phellinus linteus, were separately diluted with the natural culture media Acanthopanax senticosus. Solid-state fermentation was used to produce three different A. senticosus-fermented mushroom mycelium groups: G. lucidum mycelia, H. erinaceum mycelia, and P. linteus mycelia. The resulting mycelia were analyzed to assess their efficacies as health functional foods. Optimized fermentation conditions were determined by considering the density and growth speed of mycelia in each A. senticosus-fermented mushroom mycelium group. The cultured mushroom mycelia under the optimized conditions were extracted using water and 70% ethanol. Extraction was followed by filtration, concentration and freeze-drying to produce extract powder of A. senticosus-fermented mushroom mycelia: Water extracts (FM-5111, FM-5121, and FM-5131) and 70% ethanol extracts (FM-5112, FM-5122, and FM-5132). Analysis of extract powder of A. senticosus-fermented mushroom mycelia was performed using the maker compounds eleutheroside B and eleutheroside E. Analysis of ${\beta}$-glucan contents was performed by enzymatic procedures.