• Korean Journal of Food Science and Technology
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• v.15 no.1
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• pp.19-26
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• 1983

A study was designed to investigate the sorption characteristics of binary mixtures of NaCl and sucrose or glucose stored at various relative humidities ranging from 46% to 92%. At low relative humidity below RH 65%, the sorption equilibrium was easily achieved, whereas at higher relative humidity values over 73%, all of the mixtures tended to cintinously absorb moisture with increase in storage time. A linear equation of log $({\frac{dw}{dt}})$ = a log(t) + log(b) was found to be valid between the sorption rate and storage time with respect to storage humidities. In sucrose-NaCl mixture, the slope showed a increasing tendency as the percentage of NaCl increased in the mixture, while that of glucose-NaCl mixture failed to show a definite trend. Plateaus were obtained when the amount of water absorbed was plotted on the X axis and the percent composition of mixture on the Y axis at different storage time. The shape of plateau was varied with respect to the kind of sugar-NaCl mixture, composition of the mixture and relative humidities. A linearity was found between log(1-Aw) and the amount of water absorbed over the Aw range 0.73-0.92 and the slope was affected by the kind and composition of sugar-NaCl mixtures.

• Microbiology and Biotechnology Letters
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• v.31 no.3
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• pp.211-215
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• 2003

When Saccharomyces cerevisiae MTY62, a high-RNA content yeast, was cultivated by fed-batch mode feeding molasses and com steep liquor, the cell density less than 45g-DCW/L and the RNA content less than 140mg/g-cell were obtained, indicating that unknown compounds inhibiting the cell growth and RNA accumulation are contained in the molasses. Therefore, in order to obtain higher levels of cell density and RNA content, $Ca^{++}$, $Cu^{++}$and $K^{+}$ ions in molasses were removed by pretreatments of molasses with various agents such as IonClear BigBead, $Na_2$$HPO_4$, $H_2$$SO_4$, citric acid, $K_2$$HPO_4$, and EDT A. Among them, IonClear BigBead, $Na_2$$HPO_4$, and EDTA gave the highest $Ca^{++}$ removal efficiency of about 60-90%. In the batch culture with pretreated molasses, the cell concentration of 18.6g-DCW/I and RNA concentration of 3127 mg/I, maximum specific growth rate of 0.459$h^{-1}$ , and specific consumption rate of reducing sugar of 1.28g-sugar/g-cell-h were obtained, which are about 10%, 17%,47%, and 36% higher levels, respectively, over the batch culture with untreated molasses.

• Korean Journal of Agricultural Science
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• v.16 no.1
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• pp.118-128
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• 1989

This experiment was conducted to study the relation between the equilibrium moisture contents and the hygroscopic components in the various tobacco matters such as NC-82, Br-21, R.T.S., and puffed stem. The order of the high equilibrium moisture contents was the puffed stem, R.T.S., NC-82, and Br-21. The H-1 grades of NC-82 and Br-21 contained high contents of total sugar had higher equilibrium moisture contents than others. The moisture contents in NC-82 and Br-21 were increased at higher temperature, $30^{\circ}C$ than $20^{\circ}C$. The grades with high amounts of water extracts and total sugar affected to increase the equilibrium moisture contents in NC-82 and Br-21. In conclusion, the equilibrium contents were related to the structure of tobacco matter, the grades, the temperature, and the amount of some chemical components such as water extracts and total sugar of the leaf tobacco.

• Culinary science and hospitality research
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• v.22 no.7
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• pp.100-111
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• 2016

Tomato sauce were prepared with five different thickening agents including roux (TR), non-glutinous rice powder (TN), glutinous rice powder (TG), potato starch (TP) and tapioca starch (TT) to examine proximate composition (moisture, carbohydrate, crude protein, crude fat, crude ash, crude ash), calorie, color value, pH, salinity, $^{\circ}Brix$, reducing sugar, viscosity and sensory test (attribute difference, acceptance). The results were as follows: Moisture, carbohydrate content were the lowest while crude fat and calorie were the highest in TR (roux). On the other hand, moisture, carbohydrate content were the highest while crude protein, crude fat and calorie were the lowest in TP (potato starch) and TT (tapioca starch). Using potato starch and tapioca starch are supposed to be prepared low-fat, low-calorie tomato sauce. L value was the highest in TN (non-glutinous rice powder), a value was the highest in TP (potato starch), b values was the highest in TR (roux). pH of tomato sauce showed a range of 5.24 to 5.39. TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest in pH. TP (potato starch) was the highest salinity, reducing sugar was the lowest. TG (glutinous rice powder) was the lowest salinity, $^{\circ}Brix$ was the highest. And TR (roux) was the lowest $^{\circ}Brix$, reducing sugar was the highest. In viscosity, TG (glutinous rice powder) was the highest and TT (tapioca starch) was the lowest. The attribute difference test results was the highest in gloss, color intensity, tomato odor, tomato taste, pure taste in TT (tapioca starch) and savory taste, oily taste, thickness, residue was the highest in TR (roux). The preference test results reveal that the appearance, flavor, taste, texture and overall acceptance level was the highest in TP (potato starch) and TT (tapioca starch). The results of this study, tomato sauce prepared potato starch and tapioca starch instead of the traditional roux was higher in sensory acceptability. Recently, people is avoided high-fat and high-calorie foods, and potato starch and tapioca starch are confirmed that the tomato sauce can be made of a low-fat and low-calorie.

• Journal of Bio-Environment Control
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• v.25 no.1
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• pp.9-15
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• 2016

High temperature is one of the important environmental factors limiting cultivation of apple (Malus domestica Borkh). The expression of genes related with anthocyanin synthesis and sugar accumulation in response to high temperature was studied in the 'Hongro' apple fruits at different developmental stages in different temperature conditions through real-time PCR. Expression of ${\hat{a}}$-amylase (BMY) and polygalacturonase (PG) genes related with sugar synthesis was higher in late ripening stages than in initial ripening stages. Expression of four genes such as phenylalanine ammonia-lyase (PAL), chalcone synthase (CHS), flavanone 3-hydroxylase (F3H), and malate dehydrogenase (MDH), which were related with fruit skin coloration, increased gradually in apple fruits of the middle and late ripening stages. Interestingly, the expressions of all genes were highly inhibited expressed at $30-35^{\circ}C$ compared to $25^{\circ}C$ in all ripening stages. In the further work, investigation of expression levels of various genes could be conducted in the level of transcriptomics in fruits at the middle ripening stages to get meaningful information of ripening metabolism in apple in high temperatures.

• Korean Journal of Soil Science and Fertilizer
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• v.12 no.1
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• pp.35-41
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• 1979

A study was conducted to investigate the status of organic phosphorus in soils originated from different parent materials and under different uses(Virgin, rice soil, upland). The results are summarized as a following. 1. Regardless of parent materials and land uses, the contents of different forms of organic phosphorus are in the order of unidentified organic-P>Inositol-P>Sugar-P>Lipid-P. 2. In case of Inositol-p, the contents were in the order of rice soil>upland>virgin soil. 3. The contents of Sugar-P and Lipid-P in cultivated soils are higher than in uncultivated soil. 4. RNA and DNA are not identified in any soil when detected by ultra-violet absorption method. 5. There is highly significant correlation between the content of soil organic matter and that of organic phosphate. However, there is remarkable difference in the pattern of correlation between cultivated soils and uncultivated soils. 6. Comments were made on the factors on plant availability of various organic phosphorus.

• Korean journal of food and cookery science
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• v.29 no.5
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• pp.453-462
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• 2013

Recently, two formulas of sulgidduk added to pine needle juice (PNJ) with various physiological activities were developed for metabolic syndrome patients in our lab. According to previous studies, cooking may alter antioxidant properties by initiating destruction, release or transformation of antioxidant compounds contained in food. Therefore, the aim of this study was to compare the antioxidant activities and antigenotixic effects of sulgidduk with/without PNJ and to note changes in these activities after cooking. The ingredients of sulgidduk was added on the basis of 100% rice flour as follows: conventional sulgidduk (S): 1.5% salt, 30.0% sugar; PNJ added to sulgidduk A (PS-A): 1.4% salt, 30.0% sugar, and 1.0% PNJ; PNJ added to sulgidduk B (PS-B): 1.5% salt, 21.4% sugar, and 1.4% PNJ. Ethanol and water extracts of sulgidduk were analyzed for the total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total radical-trapping antioxidant potential (TRAP), oxygen radical absorbance capacity (ORAC), and antigenotoxic effect by comet assay. The ethanol extracts PS-A and PS-B showed higher TPC and antioxidant activities (DPPH RSA, TRAP, and ORAC) than did the S ethanol extract before cooking. The more PNJ was added, the higher TPC and anitoxidant activities were observed in sulgidduk (PS-A$200{\mu}M$ of $H_2O_2$. Taken together, this study suggests that sulgidduk added to 1.44% of pine needle juice may be a good option antioxidant and antigenotoxic source.

• Journal of the Korean Society of Food Culture
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• v.19 no.5
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• pp.499-505
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• 2004

The present study was conducted to investigate extraction characteristics and antioxidative activity of Cassia tora L. extracts. Cassia tora L. was extracted by reflux extraction under different extraction conditions including solvent. The solid yield, turbidity, color value, titratable acidity, free sugar contents, electron donating ability and superoxide dismutase-like ability of Cassia tora L. extracts were determined. The highest solid yield value was obtained with water of 10 fold. No significant difference in turbidity and color value were found among the extracts prepared with various extraction solvents, 75% ethanol, 50% ethanol and water. The highest titratable acidity was obtained with 50% ethanol of Cassia tora L.. The free sugar contents of Cassia tora L. extracted with water showed the highest value. Cassia tora L. extracts with water included higher contents of free sugar compared with then of the other solvent extracts, 50% ethanol and 75% ethanol extracts. The total polyphenol compound content of Cassia tora L. extracted with 50% ethanol showed the highest value. Cassia tora L. extracts with 50% ethanol included higher contents of total polyphenol compound compared with those of the other solvent extracts, water and 75% ethanol extracts.

• Journal of the Korean Society of Food Culture
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• v.19 no.5
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• pp.484-490
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• 2004

The present study was conducted to investigate extraction characteristics and antioxidative activity of Schiznadra chinensis extracts. Schiznadra chinensis was extracted by reflux extraction(RE) under different extraction conditions including solvent. The solid yield, turbidity, color value, titratable acidity, free sugar contents, electron donating ability(EDA) and superoxide dismutase(SOD)-like ability of Schiznadra chinensis extracts were determined. The highest solid yield value was obtained with water of 10 fold. No significant difference in turbidity and color value were found among the extracts prepared with various extraction solvents, 75% ethanol, 50% ethanol and water. The highest titratable acidity was obtained with water extracts of Schiznadra chinensis. The free sugar contents of Schiznadra chinensis extracted with water showed the highest value. Schiznadra chinensis extracts with water included higher contents of free sugar compared with those of the other solvent extracts,50% ethanol and 75% ethanol extracts. The total polyphenol compound content of Schiznadra chinensis extracted with 50% ethanol showed the highest value. Schiznadra chinensis extracts with 50% ethanol included higher contents of total polyphenol compound compared with those of the other solvent extracts, water and 75% ethanol extracts. The electron donating ability of extracts were 60.87% in water, 57.24% in 50% ethanol, and 55.61% in 75% ethanol.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.386-392
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• 2003

Physicochemical and microbiological changes of grape wine fermented and aged at 25 and $15^{\circ}C$ for 2 and 14 weeks, respectively, were investigated. Viable bacterial cell number, $3.3{\times}10^2\;CFU/mL$ at the beginning of fermentation, increased to $2.3{\times}10^6\;CFU/mL$ after 2 weeks, then decreased to $1.9{\times}10^3\;CFU/mL$ after 14 weeks. Viable yeast cell number increased from $2.8{\times}10^2\;to\;2.2{\times}10^7\;CFU/mL$ during fermentation, then decreased to $1.6{\times}10^4\;CFU/mL$ after aging. Turbidity, pH, total sugar content, reducing sugar content, and solid content of grape wine decreased during fermentation, whereas acidity and alcohol content increased to 0.64 and 8.4%, respectively. Most physicochemical properties did not change significantly during aging. When grape wine was filtered through $0.45-{\mu}m$ nitrocellulose membrane, followed by various ultrafiltration membranes with different molecular weight cut-off values, Biomax 100K membrane with $100\;L/m^2/hr$ (LMH) of initial flux was chosen for ultrafiltration process. These membrane filtration treatments resulted in complete removal of microorganisms and decreases in turbidity, reducing sugar, and solid content. Physicochemical properties of wine did not change, and no microorganisms were found during storage at $30^{\circ}C$ for 12 weeks.