• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.654-661
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• 2013

The current research is designed to analyze sterilization effects on mulberries in terms of storage temperature and storage period after treating with tap water (TW), electrolyzed water (EW) and aqueous chlorine dioxide ($ClO_2$). The treated $ClO_2$ concentrations are 10, 50, 100 and 200 ppm. In each concentration, the mulberries are soaked for 30 seconds respectively. The sterilization effects are being compared at room temperature ($25^{\circ}C$) and at $4^{\circ}C$, respectively. And the enzyme activity related to quality is also being investigated and analyzed about for browning inhibition effects. Microbial sterilizing power increases more in treating plots with EW and $ClO_2$ than treating plot with TW. Futhermore sterilizing power of $ClO_2$ increased sharply on high concentration treatment plot as well. Sterilization effects of $ClO_2$ during storage time are better at cold temperature. Pictures taken from scanning electron microscope reveal that there are no microbes in sterilizing solutions treatment plots. From measurement of the enzyme activity, it is concluded that activities decrease more in sterilizing solutions treatment plots as comparing with TW treated plot during the time. The amount of total polyphenolics decrease with the time passing and EW and $ClO_2$ treatment shows less contents than TW treatment. Thus, EW and $ClO_2$ treatment of mulberris are considered as method to improve safety by reducing total plate count and to contribute to quality maintenance and to extend storage time.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.5
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• pp.637-644
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• 2013

This study was conducted to obtain the baseline data for fermented tea with King oyster (Pleurotus eryngii) mushroom mycelium as well as to investigate the possibility of development for deodeok processing products. For this research, the physicochemical properties and antioxidant activity for fermented tea were confirmed by different roasting temperatures and roasting times. The results of the physicochemical properties, browning, turbidity, reducing sugar, total polyphenol and total flavonoid contents, were increased with increasing roasting temperature and roasting time, whereas the pH was decreased. The results of the antioxidant activity test of fermented tea, DPPH radical-scavenging activity, FRAP and reducing power, were increased with increasing roasting temperature and roasting time. The preference of fermented tea was confirmed as being the highest when roasted at $180^{\circ}C$ for 30 min. Although fermented tea did not have a unique flavor of mushroom and burnt flavor, it had strong color, flavor and taste. For this reason, fermented tea production for high content of functional materials and high preference is possible by roasting at $180^{\circ}C$ for 30 min. As for the results of this study, the physical properties of fermented deodeok were relatively stable on high temperature exposure and furthermore, the development of a variety of foods will be possible because fermented deodeok has an antioxidant capacity.

• Korean Journal of Food Science and Technology
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• v.32 no.4
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• pp.860-866
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• 2000

The efforts were made to develop persimmon leaf beverages on the basis of the results of sensory evaluation. The result of sensory evaluation for the development of persimmon leaf beverages showed that when the concentration of extracts was 10%, the aroma and flavor of persimmon leaves was best. The optimum concentration of sugar was 4.5% and apple juice was 15%. The change of pH had the tendency to keep stable range(3.82-3.71) during the period of 30 days and free-sugar had little change according to the temperature and time of preservation. The preservation of the change of ascorbic acid revealed that the range of decrease in the case of preservation at $4^{\circ}C$ was a bit narrower than in the case of preservation at $25^{\circ}C$. Nonvolatile organic acids were four kinds of acids, oxalic acid, levulinic acid, malic acid, and citric acid, among which levulinic acid was on the increase for the first 10 days during the preservation period and then on the decrease regardless of the temperature of preservation. The browning of beverages was on the slight increase.

• Journal of the Korean Society of Food Science and Nutrition
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• v.41 no.5
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• pp.591-597
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• 2012

This study was conducted to investigate the changes in chemical components and antioxidant activities of dried jujube ($Zizyphus$ $jujuba$ Miller) with different aging temperatures ($60^{\circ}C$, $70^{\circ}C$, and $80^{\circ}C$) and durations (5 days, 10 days, 15 days, 30 days, and 50 days). The browning index increased from 0.124 to 1.998 with increased aging temperature and duration. As aging duration increased, fructose, glucose, and sucrose content decreased from 24.96% to 4.96%, from 22.23% to 4.41%, and from 18.41% to 0%, respectively. Reducing sugar content decreased from 351.52 mg/g to 155.96 mg/g as aging temperature and duration increased. Total acidity slightly increased from 1.61 to 3.13%. 5-Hydroxymethyl-2-furaldehyde increased from 0.002 mg/g to 38.84 mg/g, respectively. As aging temperature and duration increased, total polyphenol content increased from 15.98 mg/g to 38.61 mg/g. DPPH and ABTS radical scavenging activities increased from 4.03 mg trolox eq/g to 22.22 mg trolox eq/g, and from 2.11 mg ascorbic acid eq/g to 13.39 mg ascorbic acid eq/g, respectively. Reducing power increased rapidly in the first stage and then slowly increased afterward.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.140-145
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• 2017

Pinus koraiensis cone (PKC) extract was prepared by mixing PKC with sugar at a weight ratio of 1:1 and then removing PKC after incubating the mixture at room temperature for 100 days. The resulting PKC extract was examined for its physicochemical properties and antioxidant activities using Prunus mume fruit extract, which is similar to PKC extract in terms of preparation procedure and product usage, as a control. PKC extract consisted mainly of moisture (21.76%) and sugar (70.03%), leading to high viscosity. PKC extract was apparently yellowish, and therefore its browning index and color intensity were appreciably lower than the control (P=0.0000), indicating that Maillard reaction was not facilitated during fermentation. Compared with the control, PKC extract was not appreciably different in terms of total flavonoid content, whereas its organic acid content and total reducing capacity were significantly lower. Nevertheless, its metal-chelating activity and DPPH radical scavenging activity were comparable to those of the control. In addition, SOD-like activity of PKC extract was 2-fold higher than that of 6.6 mM quercetin, which had a higher total flavonoid content than PKC extract. This indicates that PKC extract contains certain flavonoids with higher antioxidant activities than quercetin. The results show that PKC extract provides antioxidant activity as well as characteristically different sensory properties due to its higher sugar and lower organic acid contents compared with Prunus mume fruit extract.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.3
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• pp.342-347
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• 2007

Physicochemical properties of onion powder as influenced by drying methods were investigated. Moisture contents of onion powder were 13.29%, 12.99%, and 10.78% for samples dried using hot-air dryer, freeze dryer, and vacuum dryer, respectively. There were no significant differences in crude fat, crude protein, and crude ash content (p>0.05) depending on the drying methods. Samples prepared by freeze drying showed a significantly higher L-value as compared with those prepared by hot-air and vacuum drying (p<0.05). Scanning electron micrographs showed that freeze drying produced smaller particle-sized sample which in turn resulted in the higher porosity of the sample. Freeze dried samples revealed significantly lower degree of rehydration than other samples (p<0.05) probably due to small particle size of the sample. Water solubility of freeze dried sample appeared to be higher than that of other drying methods while the swelling ratio of the same sample appeared to be lower than that of the others. Browning index was significantly lower in samples prepared by freeze drying (p<0.05) but not significantly different between samples dried by hot-air and vacuum drying. Vitamin C content was higher in freeze dried onion powder due to the lower temperature applied to the sample. Freeze dried onion powder contained significantly lower amount of total polyphenol and higher amount of total sugar as compared to other samples (p<0.05).

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.3
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• pp.1-8
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• 2017

The present study aimed to investigate the effect of calcium chloride($CaCl_2$) on the growth and physiological responses of Pinus strobus and the variables that are sensitive to $CaCl_2$. Thus, changes in the visible damage, growth of root collar diameter, plant water content, chlorophyll content and composition, maximum PS II photochemical efficiency, and electron transport rate of P. strobus was analyzed in relation to treatment witih $CaCl_2$. A $CaCl_2$ solution(0.5, 1.0 and 3.0%) was applied in the root zone before leaf unfolding. Leaf browning, defoliation, and drying were observed with $CaCl_2$ application and this pattern was aggravated as the $CaCl_2$ concentration increased and the treatment period became longer. The decrease of growth in root collar diameter and height and leaf water content were observed at $CaCl_2$ 1.0% and 3.0%. The total chlorophyll content indicated that photopigment, PS II photochemical efficiency and electron transport rate significantly decreased at $CaCl_2$ 3.0%. In conclusion, $CaCl_2$ affected leaf water content and led to a decrease of capability in light harvesting and photochemical responses. Also, as a result of the correlation between calcium chloride concentration and growth and physiological response parameters, it was found that the leaf moisture content and the ratio of chlorophyll a and b reflect the damage level of calcium chloride sensitively because their coefficient of determinations were relatively high.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.1
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• pp.62-69
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• 2009

Maillard reaction products (MRPs) were produced from aqueous solution of various sugars with defatted hydrolyzed soybean protein (DFHSP) with different temperatures and pressures. Physicochemical properties of MRPs were investigated; also, DPPH and hydroxyl radical scavenging activity and sensory properties were evaluated. MRPs from ribose and DFHSP had the highest reactivity with larger pH reduce, higher browning index increase and higher antioxidant activity than other MRPs from other sugars. The antioxidant activities were increased with increasing temperatures and pressures of reaction. The highest antioxidant activity and sensory preference were obtained from MRPs with ribose at $140^{\circ}C$ with 2.8 kg/$cm^2$ for 30 mins.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.2
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• pp.229-236
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• 2017

This study was performed to optimize yanggaeng processing conditions prepared with different amounts of steamed Liriopis tuber (SLT) extract, sugar, and agar powder using response surface methodology. The experimental conditions were designed according to the central composite design with 16 experimental points, including two replicates for three independent variables. The experimental data on physicochemical properties, textural properties, and sensory evaluation were fitted to various models, and the accuracy of the equations was analyzed by ANOVA. Among the responses, pH, water content, sugar content, L-value, browning index, chewiness, gumminess, and sensory properties of appearance, color, sweetness, hardness, texture, and overall acceptability showed significant correlation with contents of SLT, sugar, and agar powder. From these results, optimum formulation of yanggaeng was calculated as follows: SLT 35 mL, sugar 55.23 g, and agar powder 3.39 g.

• Journal of Bio-Environment Control
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• v.17 no.2
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• pp.124-131
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• 2008

To investigate main air temperature factors correlated to difference of fruit characteristics according to cultivating areas, fruit and air temperature characteristics of eight cultivating areas of 'Fuyu' persimmon were analyzed by principle components and multiple regression analysis. The first principal components extracted from 16 air temperature factors was annual mean temperature, mean temperature during October, annual mean minimum extreme temperature, mean temperature during growing period, and so forth. The second principal components was mean temperature during May and June and so forth. And cumulative contribution was 91.4%. The five of eight cultivating area had clearly the difference of main factors or the correlated direction among cultivating areas. In multiple regression analysis between the extracted main factors and fruit characteristics, fruit hight were highly correlated with mean temperature during growing period ($X_8$) and cumulative temperature ($X_6$), and the regression equation was $Y=150.55-5.375X_8+ 0.014X_6(r^2=0.843)$. Also this regression equation was affected by mean minimum temperature during growing period, cumulative temperature, and mean temperature during August. Fruit diameter was negatively correlated with mean temperature during growing period, flesh browning rate and Hunter a value of peel color were positively correlated with mean minimum temperature during growing period and annual minimum air temperature, respectively.