• Journal of the Korean Society of Food Culture
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• v.20 no.5
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• pp.508-515
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• 2005

The effect of glue plant(Codium fragile) on the Dongchimi fermentation was investigated by measuring physicochemical properties during fermentation at $10^{\circ}C$. Dongchimi was prepared with various levels(0, 0.5, 1.0 and 1.5%) of glue plant(Codium fragile). The pH of Dongchimi decreased slowly in all samples during fermentation. Total acidity of Dongchimi increased gradually during fermentation and total acidity of Dongchimi with glue plant(Codium fragile) was higher than that of control. Redox potentials decreased until 30 days of fermentation but increased thereafter. Reducing sugar content increased in the initial stage of the fermentation periods, and then decreased gradually. The reducing sugar content of Dongchimi with glue plant(Codium fragile) was higher than that of control. The content of total vitamin C was much higher in dongchimi with glue plant(Codium fragile). In color measurement, lightness value decreased gradually. However, redness and yellowness values increased gradually during fermentation but decreased thereafter. The content of hot water soluble pectin(HWSP) decreased as the fermentation proceeded, but the content of hydrochloric acid soluble pectin(HClSP) and sodium hexametaphosphate soluble pectin(NaSP) increased.

• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.1032-1038
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• 2008

This study was conducted to develope carbohydrate-based fat replacement for use in the preparation of non-(trans) fatty acid and low-caloric bread. Characteristics such as leavening height of batter, pH, titratable acidity, specific volume, sensory evaluation, shelf life and texture change of bread made using 11 types of carbohydrate-based fat replacements were measured. The 11 carbohydrate-based fat replacers (No. $1{\sim}11$) were prepared using maltodextrin as a base, and different ratios of calcium sulfate, ascorbic acid, sodium stearoyl lactylate and methyl cellulose. The pH was lowered and the total titratable acidity was increased after four hours of fermentation in the control and the samples of dough that contained the fat replacement. In addition, the leavening height of the control was 5.0cm (maximum) after two hours of fermentation and 4.6 cm after four hours of fermentation, which was similar to the heights observed when No.$9{\sim}11$ were evaluated. When the specific volume of the bread was evaluated, the 3% of fat replacement No. 10 produced the best results. When taste was evaluated, there was no significant difference between the control and the bread produced using 1% No. 10, however, there was a significant difference between the control and all samples that contained 2% or more of the fat replacement. Furthermore, the addition of a greater concentration of the fat replacer resulted in a greater moisture. However, there were no significant differences in the color of the control and any of the samples. Additionally, measurement of the firmness of the bread during four days of storage at $25^{\circ}C$ revealed that it decreased as the concentration of fat replacer increased. In addition, the sample that contained 3% of sample No. 10 showed a firmness of 18kgf after three days of storage, while the control showed a firmness of 18kg after two days, which indicates that the degradation of the bread that contained the fat replacer was delayed by one day. The bread made using fat replacers was found to have a better taste, flavor, color, texture and firmness than the control, and the best results were observed in response to the addition of 3% of replacement No. 10. The results of this study will be useful in the production of non-(trans) fatty acid, low caloric bread.

• Journal of Korean society of Dental Hygiene
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• v.21 no.5
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• pp.517-526
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• 2021

Objectives: This study was conducted to analyze the sugar content, acidity, and viscosity of the Korean frozen desert. Methods: A total of 60 types of frozen desserts marketed in Korea were randomly selected and classified into frozen desserts, milk-fat ice cream group, and non-fat ice cream group according to the classification criteria for frozen desserts. Each product was treated under the same conditions to investigate the component of each product, and sugar content, acidity, and viscosity were measured. Frequency analysis and one-way ANOVA were performed. Results: As a result of analyzing the characteristics related to dental caries activity by group, the frozen dessert had the lowest average pH of 3.67, and the sugar content was significantly higher in the milk-fat group (33.22) and non-fat group (32.89) than in the frozen dessert. The viscosity was also the highest in the milk-fat group at 32.62, and the frozen dessert was significantly lower at 9.42. Conclusions: Due to the abnormal temperature and spread of the coronavirus, consumption of frozen desserts at home is on the rise. To prevent dental caries in children, education is needed for children and their guardians for proper oral care after eating frozen desserts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.5
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• pp.600-607
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• 2017

The total acidity (TA) of Makgeolli was affected by suspended solids and $CO_2$ produced during the fermentation process. Nine Makgeollis (four sterilized and five unsterilized Makgeollis) were collected in the market, and their TAs were compared before and after filtration and $CO_2$ removal. TAs of sterilized Makgeollis were 0.379~0.477%, which significantly decreased to 0.167~0.225% after filtration and 0.132~0.170% after $CO_2$ removal (P<0.05). TAs of unsterilized Makgeollis were 0.412~0.467% and decreased to 0.157~0.365% after filtration and 0.143~0.280% after $CO_2$ removal (P<0.05). TAs of Makgeollis were compared by three methods using different indicators. The TAs of sterilized and unsterilized Makgeollis were 0.105~0.123% and 0.105~0.200%, respectively, by bromthymol blue+neutral red (light green), 0.129~0.154% and 0.130~0.255%, respectively, by phenolphthalein (faint pink), and 0.120~0.146% and 0.130~0.232%, respectively, by bromthymol (blue). Nowadays, Makgeolli is commercialized with various distinct colors, and thus it is important to select appropriate indicators for proper titration endpoint identification for TA measurement. The compositions of organic acids profiles varied depending on sterilized or unsterilized Makgeollis, in which oxalic acid (0.108~0.329 mg/mL), malic acid (ND to 0.134 mg/mL), lactic acid (0.127~0.776 mg/mL), and citric acid (ND to 1.159 mg/mL) were found, and lactic acid was in unsterilized more than sterilized Makgeollis.

• Journal of Korean Society for Atmospheric Environment
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• v.15 no.4
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• pp.403-415
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• 1999

To properly assess air pollution levels, application of quality assurance and quality control(QA/QC) is believed to be an essential step. In order to cope with such scientific principle, a field study was designed with an aim of comparing: 1) the methods of calibration for airborne pollutants and 2) the protocols developed for their measurements. Measurements were made at Han Yang University, Seoul during 29 May through 1 June 1998 under the management of the Division of Measurements and Analysis(DMA) of Korean Society for Atmospheric Environment(KOSAE). In this work, we report our results of intercomparative measurements on several gaseous criteria pollutants that were investigated mainly by the two institutes-Seoul National University(SNU) and the Korean Research Institute for Standards and Science(KRISS). Although measurements of major gaseous pollutants had been made routinely by many scientific institutes and organizations in Korea, most scientists involved in those studieswere obliged to do their experiments on the basis of their own procedural steps spaning from the preparation of gaseous standards to the methodological selections for the calibration. Hence, this campaign offered a unique opportunity to examine many important aspects on the measurements of these important gaseous pollutants. In the course of our study, we investigated the compatibility of data sets obtained by the two institutes in concert with reference data sets collected concurrently from a government-managed monitoring station. On the basis of our study, we conclude that different data sets made by different participants during this campaign agree well within the reasonable range of uncertainties.low, which indicated that during this period the potential acidity of precipitation was high but the neutralizing capacity was low. For Spring, pAi was very low but pH was slightly high. This was likely due to the large amount of $CaCO_3$ in the soil particles transported over a long range from the Chinese continent that were incorporated into the precipitation, and then neutralized the acidifying species with its high concentraton.

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

• Korean Journal of Food Science and Technology
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• v.22 no.2
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• pp.140-144
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• 1990

This study was undertaken to examine if sodium acetate and/or calcium chloride would increase the firmness and/or retard rancidity of Kakdugj (Korean seasoned pickles of cubed radish roots) during short $(at\;20^{\circ}C)$ or long $(at\;4^{\circ}C)$ period of fermentation During the fermentation periods, pH and acidity were higher in Kakdugis containing 0.3 or 0.6% Na-acetate than in the other samples at both storage temperatures. Firmness was increased with addition of 0.05% Calcium chloride and synergistic effect on firmness was observed when Calcium chloride and Na-acetate were added together. Sourness did not decreased in samples containing 0.3% Na-acetate at either fermentation periods but decreased in those containing 0.6% Na-acetate and stored for long. Saltiness was increased slightly with the addition of Calcium chloride. Compression test gave closer result to sensory evaluation than puncture test In the measurement of firmness with Instron.

• Culinary science and hospitality research
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• v.23 no.2
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• pp.181-188
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• 2017

Aronia is a superberry that contains antioxidants. Due to its nutritional value, it has received much attention and has been widely researched. In this study, the proportion of aronia powder applied to spelt wheat flour was measured with the pH ratio of the additive and respondents' preference was examined for the preferred addition to the additive population. As a result of the acidity measurement, the pH value tended to decrease as the amount of aronia powder was increased. As for the fermentation expansion rate, the volume of the dough added with aronia powder was measured to be slightly smaller than that without addition of aronia powder. Preference of breads with aronia powder added showed higher preference when 6% was added compared to when 3% of aronia powder was added. As a result of preference survey of breads containing aronia powder, the most preference was given to taste when 3% of aronia powder was added. Color, fragrance, and overall acceptance were the most preferred when 6% of aronia powder was added. Based on these results, the optimal mixing ratio of aronia powder to spelt flour bread was selected to be 6% of aronia powder.

• The Korean Journal of Community Living Science
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• v.24 no.2
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• pp.251-258
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• 2013

Korean oil and honey Yukwa has been paid attention as formal cake for traditional national seasons' holiday and religious service. Quality of Yukwa, however, has been maintained arbitrarily by each Yukwa manufacturer. Since even same Yukwa had severe differences in size, weight, and pattern, it has given the negative effect to the consumer. Yukwa industries need to setup the quantitative quality specifications instead of qualitative ones to maintain the uniformity of Yukwa quality. Efficient and economical inspection and process control system should be developed. In developing quality standards of Yukwa, features which can measure quality quantitatively in real time should be properly chosen. Existing quality features such as acidity, oxidization, hardness, viscosity, and texture were measured by the chemical or physical base destructive methods. Many research and developments have been performed in investigating and analyzing chemical transition states of those quality features as environment or storage condition changes. Most methods, however, require either off-line or complex treatment or time consuming process of analysis in evaluating quality features. Consumer, however, selects products mostly based on the external features such as shape, size, and color. Therefore, critical visual quality features should be chosen and the efficient real time measurement system must be developed. In this paper, computer image acquisition and processing system were developed and software modules were developed to extract the quantitative data of those features in real-time. Computer image processing system will promote in maintaining uniform quality of Yukwa and establishing quality standards of Yukwa.

• Korean Journal of Food Science and Technology
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• v.36 no.6
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• pp.911-918
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• 2004

Three dry red, four sweet red, and two white wines were prepared with domestic grape varieties: Gerbong (G), Campbell Early (C), Muscat Bailey A (M), Seredan (Sd), Seibel (Sb), and Neo-muscat (N). Sample wines were analyzed for titratable acidity, ethanol, pH, sugar content, color intensity and hue, and total phenolic content. Preferences of color, aroma, and overall acceptability were determined by 97 panelists using 9-point hedonic scale. Sweetness, sourness, astringency levels of developed wines were evaluated using 9-point just-about-right (JAR) scale. Mean overall acceptability score of C (6.49) was highest among dry red wines (p<0.05). Among sweet red wines, mean overall acceptability score of Sd (3.27) was significantly lower than those of other wines (p<0.05). In white wines, overall acceptability score of Sb (5.20) was slightly higher than that of N (4.92). Overall sourness levels in dry red wines were higher than optimum level. Based on the results, should be lowered, and sweetness and sourness levels of white wines need to be adjusted sweetness levels of C, G, and Sd for the production of sweer redwines. C and M varieties were considered to be suitable for Korean red wine production.