• Journal of Environmental Impact Assessment
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• v.21 no.1
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• pp.81-91
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• 2012

In this study, it is grasped the status of nutrients through an investigation of release characteristics and physicochemical properties of sediments on reservoir. And then the effect of sediments is evaluated on the water quality in reservoir. In the results of physicochemical analysis, the pollution level of midstream is the highest, which shows the traits that the water is more deeper and takes place a deposition consistently. Then, the pollution level of upstream is higher than downstream's because inflow has influence on the upstream directly. The downstream is located near tidal gate so that the soil particles can be moved easily and are difficult to be deposited due to the distribution of seawater by control of tidal gate. Therefore, the downstream is showed the lowest pollution level than the others. Also, the concentration of SOD(Sediment Oxygen Demand) in the upstream which is influenced on the effect of inflow is highest than the others. When it analyzes under anaerobic and aerobic condition to understand the release characteristic of sediment, it shows that the release rate is low or negative under the aerobic condition. Whereas the release rate is usually positive under the unaerobic condition relatively. According to these results, it is necessary to maintain the proper environmental factors of water body for decreasing the release rate of sediment. Because the release rate is changeable under the different condition of water body. Therefore, proper strategies are required for increasing the self-purification of water as well as keeping the aerobic condition of sediment and managing a sediment layer directly to control the inner-pollution by the sediment of reservoir.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.54-58
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• 2016

Physicochemical and sensory characteristics of persimmon jelly products with different levels (3, 5, and 7% w/w) of Daebong ripened persimmon puree was investigated. The moisture content of all jelly products used in this experiments was maintained within $8{\pm}2%$ of the products. Levels of crude chemical composition (moisture, crude protein, crude lipid, and crude ashes), texture, soluble materials, vitamin C, dietary fiber and ${\beta}$-carotene were increased as amount of puree addition increased in the products. Color values, $L^*$, $a^*$, and $b^*$ of the persimmon jelly products were 33.08-42.04, 0.93-1.31 and 8.85-11.21, respectively. There was no significant difference in pH (5.51-5.61) as the levels of Daebong ripened persimmon puree increased. Sensory evaluation in terms of appearance, color, taste, flavor, chewiness, and overall acceptance resulted in the highest score in the persimmon jelly product with 5% level of Daebong ripened persimmon puree. In conclusion, level of Daebong ripened persimmon puree affected color value, texture and vitamin C, dietary fiber, and ${\beta}$-carotene content of the persimmon jelly products. In addition, optimum level of Daebong ripened persimmon puree would be 5% for manufacturing the persimmon jelly product.

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.228-235
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• 2008

In this study, vinegar disinfection was evaluated as a novel method for the preparation of raw food ingredients used in foodservice operations. The test materials were washed and disinfected using three different methods, and were then stored at temperatures of $3^{\circ}C\;and\;10^{\circ}$ for 7 days; Following storage, physicochemical and sensory characteristic comparisons were performed. Temperature for all test materials ranged between 15.2-20. $9^{\circ}C$, water activity was maintained near 0.96, and the pH levels of the samples were 6.44, 6.29, and 6.35, respectively. Residual chlorine levels were generally low, ranging between 0.01 and 0.02. The physicochemical qualities of the samples were evaluated according to the storage method and temperature. Brightness(L value), redness(a value), and yellowness(b value) tended to increase with increasing storage time. The evaluated sensory characteristics included appearance, color, smell, taste, texture, and overall acceptance. With regard to storage temperature the vinegar-treated samples were evaluated as superior, receiving a score of 7.00, and the ingredients stored at $3^{\circ}C$ were evaluated as significantly (p< 0.001) superior to those stored at $10^{\circ}C$. Overall, vinegar is an effective disinfectant to apply in the preparation of raw vegetables that are typically served without heating, and which can cause serious food safety issues when contaminated.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.515-525
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• 2023

This research aimed to examine the effects of grapefruit seed extract (GSE) at various concentrations on the microbial safety and physicochemical characteristics of onion puree (0.01~0.1%). The onion puree was kept at 4℃ for 14 days. The results of the study indicated that the addition of GSE did not cause any significant changes in the sample's brix degree and viscosity in onion puree (p<0.05). However, as the concentration of GSE increased, the pH level decreased. On the other hand, as GSE was added, the lightness of the onion puree increased, while the redness and yellowness decreased. Compared to pure onion puree, the GSE-incorporated onion puree had higher levels of total flavonoid and total polyphenol content, indicating that it helps to maintain antioxidant activities. Based on the microbial safety test, aerobic bacteria, yeast, and mold were absent until day 14 of storage. In conclusion, the study suggests that the addition of GSE to onion puree increases its antioxidant activity and shelf-life.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.6
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• pp.855-864
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• 2016

The objective of this study was to compare the physicochemical and nutritional properties of breast and thigh meat from commercial Chinese crossbred chickens (817 Crossbred chicken, 817C), imported commercial broilers (Arbor Acres broiler, AAB), and commercial spent hens (Hyline Brown, HLB). The crossbred chickens, commercial broilers and spent hens were slaughtered at their typical market ages of 45 d, 40 d, and 560 d, respectively. The results revealed that several different characteristic features for the three breeds. The meat of the 817C was darker than that of the other two genotypes. The 817C were also characterized by higher protein, lower intramuscular fat, and better texture attributes (cooking loss, pressing loss and Warner-Bratzler shear force [WBSF]) compared with AAB and HLB. The meat of the spent hens (i.e. HLB) was higher in WBSF and total collagen content than meat of the crossbred chickens and imported broilers. Furthermore, correlation analysis and principal component analysis revealed that there was a clear relationship among physicochemical properties of chicken meats. With regard to nutritional properties, it was found that 817C and HLB exhibited higher contents of essential amino acids and essential/non-essential amino acid ratios. In addition, 817C were noted to have highest content of microelements whereas AAB have highest content of potassium. Besides, 817C birds had particularly higher proportions of desirable fatty acids, essential fatty acids, polyunsaturated/saturated and (18:0+18:1)/16:0 ratios. The present study also revealed that there were significant differences on breast meat and thigh meat for the physicochemical and nutritional properties, regardless of chicken breeds. In conclusion, meat of crossbred chickens has some unique features and exhibited more advantages over commercial broilers and spent hens. Therefore, the current investigation would provide valuable information for the chicken meat product processing, and influence the consumption of different chicken meat.

• Journal of Wetlands Research
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• v.20 no.4
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• pp.322-329
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• 2018

In this study the community characteristics of benthic macroinvertebrates distributed in stream of Gaya Mountain were figured out and the correlation with the physicochemical water quality factors were calculated. During the study period, total 4 phyla, 6 classes, 13 orders, 36 families, 100 species of benthic macroinvertebrates were recorded. Ephemeroptera were the most dominant followed by Trichoptera, Plecoptera, Diptera, Non-insecta, Hemiptera, and Odonata. The overall dominant species was Cincticostella levanidovae by dominance rate in 17.72%, subdominant species was Hydatophylax nigrovittatus by dominance rate in 6.15%. The biotic indices showed the diversity index 5.17, richness index 12.44, dominant index 0.24 and evenness index 0.78, there is no absolutely dominant benthic macroinvertebrates in the stream of Gaya Mountain. We identified the correlation between the species number and individuals of main taxa and the physicochemical water quality factors. Ephemeroptera and Plecoptera showed a negative correlation with water temperature, but they represented a positive correlation with the dissolved oxygen. This results suggest that water temperature and dissolved oxygen are important physicochemical water quality factors affects the distribution of Ephemeroptera and Plecoptera, the indicators of clean water stream.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.6
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• pp.837-842
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• 2010

The physicochemical properties of coarse semolina (CS), medium semolina (MS) and fine semolina (FS) were investigated to research method applied in noodles processing of Korean wheat semolina. Large particle (>250 ${\mu}m$) was over 75% in all semolinas, except for FS, and the particle distribution of MS and durum semolina (DS) was similar. Crude protein and crude ash were the highest in DS followed by CS>MS>FS. Crude lipid of DS was the lowest among samples and CS, MS and FS were not significantly different. L value was high in semolina with small particle distribution and starch damage was the lowest in DS followed by FS>MS. Amylose content was high in DS (29.80%) and FS (29.08%) with small particle distribution. Water binding capacity was the highest in DS, and FS showed the highest water binding capacity among Korean wheat samples. Solubility and swelling power were noticeably high in FS with low starch damage and small particle distribution. In scanning electron microscope (SEM), FS and MS showed distribution of separated fine particles of flours. From these results, the physicochemical properties of semolina showed many differences by grinding methods. FS should be applied in noodles processing through additional examination about characteristic of noodle making.

• Journal of the Korean Society of Food Science and Nutrition
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• v.39 no.9
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• pp.1399-1404
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• 2010

Physicochemical characteristics and antioxidant activities of twelve varieties of legumes and cereals in Korea were analyzed and compared. Crude protein content was higher in legumes (20.60~34.47%) than in cereals (8.96~15.45%). Crude fat contents of soybean (17.73%) and black soybean (18.79%) were higher than other legumes (0.68~1.38%) and cereals (1.01~5.39%). The major minerals were potassium, calcium and sodium, and especially calcium and potassium were high in legumes. Unsaturated fatty acids composition ranged from 66.79% in cowpea to 85.14% in soybean, and $\Omega$-3 fatty acids (linolenic acid) content was higher of 7.47~48.25% in legumes than 0.36~3.71% in cereals. Total polyphenol content was higher 1.32~4.15 mg/g in 80% EtOH extracts from legumes than 0.53~2.83 mg/g in cereals. DPPH and ABTS radical scavenging activities were high values of 62.60% and 264.20 mg AA eq/g, respectively, in EtOH extract from sorghum.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.309-314
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• 2007

The physicochemical and sensory characteristics of rice wine, Yakju, made with different additions of red yeast rice (0, 10, 20, 30, and 40%) were investigated. The pH of the rice wine decreased and the total acidity increased with greater additions of red yeast rice. Furthermore, the total sugar content increased and the alcohol content decreased with increasing amounts of red yeast rice. The color L-value diminished and the color a- and b-values increased with increasing amounts of red yeast rice. Among the volatile flavor compounds, esters, aldehydes, alcohols, and acids were the most important aroma-active compounds identified in the rice wine. The sample with the 10% red yeast rice addition had the highest ester content, which is a primary component in fruit fragrance. The highest overall acceptability values in the sensory test for color, flavor, taste, and overall favorite were 5.10, 5.75, 5.15, 4.65, and 4.50, respectively, with the addition of 10% red yeast rice.

• Food Science and Preservation
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• v.12 no.5
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• pp.442-448
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• 2005

To develop efficient drying method, one of important process in manufacturing of Saengsik, uncooked food, the change of physicochemical characteristics and functional component contents of cereals dried by various drying methods was investigated. The proximate composition and dietary fiber content of rice, brown rice, glutinous rice and barley showed little changes during hot-air drying (50$\circC$, 55$\circC$, 60$\circC$) and freeze-drying. Yellowness(b) value of hot-air dried products was higher than one of freeze-dried products. The content of niacin was 0.77 mg% in milled rice, 1.84 mg% in brown rice, 0.68 mg% in glutinous rice, 1.00 mg% in barely dried by hot-air at 60$\circC$ and was lower than those of other samples. $\beta$-glucan content in barely was not changed by hot-air drying and freeze-drying method. In conclusion, hot-air drying would be recommended for barley having $\beta$-glucan, a kind of functional components and freeze-drying should be used for raw materials having heat-labile components such as niacin.