• Journal of the Optical Society of Korea
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• v.19 no.6
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• pp.700-704
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• 2015

As pH is a widely used index in chemical, medical, and environmental applications, research on pH sensors has been active in recent years. This study obtained RGB values by measuring the reflected light from a liquid sample to detect fine changes in pH, and performed mathematical modeling to investigate the relationship between the detected optical signal and pH value. Also, the trends in pH changes were easily identified by analyzing RGB values and displaying them in the color coordinate for easy visualization of data. This method implemented a user-friendly system that can measure and analyze in real time. This system can be used in many fields such as genetic engineering, environmental engineering, and clinical engineering, because it not only can measure pH but also replaces a colorimeter or turbidimeter.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.869-874
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• 2006

This study investigated the effect of bamboo leaf powder, added at content of 0%, 3%, 6%, 9% and 12%, on the quality and sensory characteristics of rice cake imprinted with flower pattern (Ed-there is no respecitive comparison here) The chemical composition as a whole was 3.07${\pm}$0.12% of moisture, 5.87${\pm}$0.02% of crude protein, 2.52${\pm}$0.05% of crude fat, 23.70${\pm}$0.07% of crude fiber and 7.73${\pm}$0.02% of crude ash. With increasing amount of added bamboo leaf powder, the hardness and chewiness of the cake were significantly increased(p<0.05), while the cohesiveness, springiness and adhesiveness were decreased. In chromaticity, the L-value, the indicator of brightness, was significantly decreased with increasing bamboo leaf powder content. The a-value, the indicator of redness, was significantly lower than the chlorophyll color (p<0.05). The b-value, the indicator of yellowness, was increased indirect proportion to the content. In sensory test, the sensory characteristics such as color, flavor, taste and chewiness were all stronger with increasing powder content, whereas the softness and dampness were weaker. The greatest overall satisfaction was achieved by the sample group of cake with 6% preference added powder.

• Culinary science and hospitality research
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• v.18 no.5
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• pp.256-266
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• 2012

The purpose of this study is to decide the optimum amount of ginger, which draws attention as a functional food nowadays, to make ginger muffins and to serve the basic data for functional bakery products added with ginger juice. As measurement items for quality characteristics, I tested height, weight, volume, specific volume, moisture, pH, chromaticity, texture and organic functions of muffin by adding 10%, 20% and 30% ginger juice respectively comparing with general ingredients plus water amount used to make muffins. Height decreased with the amount of the addition increased, and there was no significant difference in weight. The volume and specific volume measurements of the muffins showed a lower value with the amount of the addition increased, which showed a significant difference. The moisture contents of the muffins increased with the amount of the addition increased. In the pH measurement, 0, 10, and 20% showed no significant difference while 30% showed a significant difference. Color measurement found that lightness and yellowness decreased with the amount of the addition increased, which showed a significant difference; redness showed high values, which indicated significant differences among all the samples. Texture measurement found that hardness showed significant differences among all the samples; cohesiveness showed a significant difference between the control and the treatment group; resilience/springiness increased with the amount of the addition increased. There were no significant differences in gumminess while chewiness increased with the amount of the addition increased. The sensory evaluation showed the lowest color with the amount of the addition increased; 10% addition was most preferred in flavor and taste; there was no significant difference in texture; there was no significant difference in 0, 10, 20% additions in overall acceptability. Taking the quality assessment and the sensory evaluation together, it is considered that general tastes of ginger muffins can be improved when ginger juice addition is 10% of water amount used.

• Food Science and Preservation
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• v.20 no.4
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• pp.488-494
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• 2013

The study was done in order to investigate the effects the red onion powder on the quality characteristics of the Korean steamed rice cake, Seolgiddok, with 3%, 6%, 9% and 12% of the red onion powder weight in control. The moisture content of the control with 0% red onion was 43.74% and it steadily decreased with the increase in powder (12%) resulting to the lowest at 37.02% for the cake. The springiness, adhesiveness and chewiness of the cake decreased according to the increase in powder content, while the hardness and cohesiveness increased together with the increase in powder content. The Hunter color value L in the chromaticity of the cake significantly decreased with the increase in powder content. The a value of the control was 2.18 and was redder with the increase in powder content, while the b value significantly increased together with the increase in powder content. The sensory characteristics of the cake such as color, flavor, taste and softness and chewiness increased along with increase in powder content. The overall taste was judged to be the best for the sample with the 9% added powder.

• Food Science and Preservation
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• v.19 no.4
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• pp.510-518
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• 2012

In this research, to modernize traditional food and to make functional bokryung-byung, bokryung-byungwas made with Poriacocos Wolf powder added. During its storage, its moisture content ranged from 42.89 to 44.85%. The control group had the highes tmoisture content (44.85%), and it was reduced significantly as the Poriacocos Wolf powder in creased. The longer the storage period was, the lower the pH and the higher the acidity was. The total bacterial count increased from 2.70 to 3.00 Log CFU/g right after the manufacture and increased rapidly on the fourth day of the storage with more than 7.00 Log CFU/g. There was no difference between the control group and the bokryung-byung, though. The Hunter's color value after the manufacture, with the increase in the added Poriacocos Wolf powder, showed a significantly reduced brightness, but significantly increased redness and yellowness. Their chromaticity did not change, how ever, during their storageat a temperature of $20^{\circ}C$. The hardness, solidity, gumminess, and cohesiveness of the bokryung-byung increased, unlike in the control group, and its brittleness increased. In terms of the overall preference, the preference for the control group was high, but was higher when 5 % Poria cocos Wolf powder was added during the manufacture of the bokryung-byung. As a result of these correlations, it is believed that elastic and chewy dduks are preferred and bokryung-byungs could be developed as functional dduks.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.730-738
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• 2017

In this study, we investigated the physicochemical properties of coffee brews according to coffee bean grinding grade. We also examined the effect of grinding grade on amounts of volatile flavor compounds. Coffee brew samples were separated using standard sieves (with pore sizes of 850, 600, and $425{\mu}m$), making particle sizes of ground beans as follows: whole bean (control), $850{\mu}m$ or more (coarse), $850{\sim}600{\mu}m$ (medium), $600{\sim}425{\mu}m$ (fine), and $425{\mu}m$ or less (very fine). For each particle size category, pH, total acidity, brown color intensity, chromaticity, total phenolic content, caffeine content, chlorogenic acid content, and total amounts of volatile flavor compounds generated were compared and analyzed. As grinding grade decreased, pH and brown color intensity increased from 4.84 to 5.18 and from 0.257 to 0.284, respectively, whereas total acidity decreased from 0.31 to 0.17%. As grinding grade decreased, the $L^*$ and $a^*$ color values decreased; however, $L^*$ value did not exhibit a significant difference depending on the grinding grade. The $b^*$ value was 15.75 in the very fine size category, which showed the highest yellowness. There was an 11 or higher color difference between the control and ground coffee powder, indicating a remarkable color difference. The total phenolic, caffeine, and chlorogenic acid contents of the coffee brewed from ground beans with a very fine size were 4.54 mg gallic acid equivalent/mL, $733.0{\mu}g/mL$, and $383.7{\mu}g/mL$, respectively, which were high values. The total amounts of volatile compounds in the very fine size category were found to be greater than 100 mg/kg. In this study, we suggest the basis for coffee quality evaluation, which involves evaluating changes in the physicochemical properties and amounts of flavor compounds of coffee relative to the grinding grade of the beans (basic step of coffee extraction).

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.840-845
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• 2007

The chromaticity, mechanical, and sensory properties of madeleine were investigated during its manufacturing process based on additions of black bean chungkukjang flour containing functional health ingredients and a high nutritient value. 1. The moisture content decreased with increasing content of the chungkukjang flour$(16.1{\sim}13.7%)$. 2. The brightness of the Madeleine decreased significantly from 75.24 to 53.61 by increasing the content of the black bean chungkukjang flour. The degree of red color increased significantly from -0.31 to 4.93 by increasing the content of the black bean chung kukjang flour. 3. For the mechanical properties, the hardness increased significantly with increasing amounts of the black bean chungkukjang flour (p<0.05). The degree of fracturability, adhesiveness, and gumminess also increased with the increasing the content, but the fracturability showed no difference by either addition. The springiness and cohesiveness decreased significantly by increasing the content of the black bean chungkukjang flour, showing an opposite result compared to the hardness. 4. The results of the sensory evaluation indicated significant differences in color among the samples(p<0.05). The color of the madeleine samples with added black bean chungkukjang flour was more preferred than that of the sample without any additive. The degree of preference increased in the order of the quantity of the additive. The moistness and softness became significantly drier and less soft, respectively, with an increasing quantity of the black bean chungkukjang flour (p<0.05). For the overall acceptance, the BC10 sample added with 10% of black bean chungkukjang flour added had the highest acceptance. This may be because it did not have a strong chungkukjang odor and had the fewest differences from the control Madeleine without the additive, in terms of its moistness and softness. Based upon these results, adding10 % of black bean chungkukjang flour in the manufacture of Madeleine is an appropriate quantity with regard to its structural and sensory characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.12
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• pp.2019-2027
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• 2013

In this study, we tried to develop a coating agent for the fresh-cut fruits used in cakes. First, the coating agent mixing ratios of sugar, pectin, sodium alginate, carrageenan, xanthan gum, vitamin C, and purified water were selected to be 55, 2, 2, 0.04, 0.1, 0.05, and 40.81% (w/w), respectively. In a freeze-thaw stability of the coating agent, the viscosity remained constant for 3 cycles of freezing and thawing repetition process, but showed a slightly decreasing trend in the 4th repetition process (P<0.05). On the other hand, the sugar content, pH, and chromaticity remained constant even in the 4th repetition process. Pineapple coated with the coating agent had smaller weight loss, hardness changes, and total bacteria distribution compared to the uncoated pineapple (P<0.05). In the chromaticity, both of the two pineapples experienced browning with increasing storage duration, as L value decreases and b value increases. However, when the color difference was compared, the progress of browning for the uncoated pineapple was faster than the coated pineapple. Also, the progress of browning at $4^{\circ}C$ was found to be slower than the progress of browning at $25^{\circ}C$. Therefore, the storage stability of the fresh-cut fruits could be improved by coating the fresh-cut fruits for cakes with the coating agent and storing at a low temperature, which would contribute to extending the shelf-life of cakes.

• Culinary science and hospitality research
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• v.22 no.7
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• pp.112-130
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• 2016

In this study the moisture content and chromaticity of fresh made lotus leaf powder added Cheongpomuk to utilize various efficacy of lotus leaf for processed food, as well as chromaticity, moisture content change, texture, total phenolic compound content, DPPH radical scavenging ability and preference of lotus leaf powder added Cheongpomuk with different storage period have been measured and analyzed. From the texture of lotus leaf powder added mung bean as per the storage period, the hardness of fresh Cheongpomuk were $0.38g/cm^2$ from control group, $0.40g/cm^2$ from CCD 1% group, $0.42g/cm^2$ from CCD 3% group, $0.37g/cm^2$ from CCD 5% group, $0.42g/cm^2$ from GGD 1% group, $0.39g/cm^2$ from GGD 3% group, $0.35g/cm^2$ from GGD 5% group, $0.39g/cm^2$ from JLD 1% group, $0.33g/cm^2$ from JLD 3% group, and $0.32g/cm^2$ from JLD 5% group. It has shown that JLD 5% group was the lowest, while CCD 3% group and GGD 1% group were the highest, and there were significant differences among sample groups. For DPPH radical scavenging ability, that of GLD 5% group was 22 times higher than that of control group. In addition, the tendency was increasing by increasing the adding rate of lotus leaf powder though there was some tolerance among sample groups. For total phenolic compound content, that of control group was 6.65 mg CE/100 g, and others were 7.48 mg CE/100 g from CCD 1% group, 15.82 mg CE/100 g from CCD 3% group, 20.15 mg CE/100 g from CCD 5% group, 15.55mg CE/100 g from GGD 1% group, 23.02 mg CE/100 g from GGD 3%, 26.95 mg CE/100 g from GGD 5% group, 3.92 mg CE/100 g from JLD 1% group, 16.72 mg CE/100 g from JLD 3%, and 26.58 mg CE/100 from JLD 5% group. From the analyzing result of responses for color and scent, taste, elasticity, and total preference of lotus leaf powder added Cheongpomuk between two panel groups, there was significant difference for the color, higher from professional cooking instructor group, but there were no significant difference between two groups for all other factors among professional cooking instructors and cooking department students. According to the results, it is expected that various functional foods can be developed by utilizing lotus leaf powder, depending on the growth condition and cultural environment of each region by adding 3% of lotus leaf powder, would be the most suitable recipe for Cheongpomuk.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.642-649
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• 2006

The browning of soy sauce is caused by the reaction of amino-carbonyl between amino-compounds and reducing sugar. Only a few studies have investigated the formation of melanoidins in UHYUKJANG. The objectives of this study were to analyze the brown pigment of UHYUKJANG and to investigate the characteristics of UHYUKJANG in comparison with soy sauce and model melanoidins. The samples were ripened for 0, 60, 120, 180, 240, 300 and 360 days at 4$^{\circ}C$ and 20$^{\circ}C$. The pH, absorbance at 420 nm absorbance ratio of 400 to 500 nm and UV-VIS spectra as an index of color intensity were measured. Additionally, L, a and b values of the samples and the amount of 3-Deoxyglucosone(3DG) in the samples were measured. The pH of both soy sauce (from 6.26 to 5.52) and UHYUKJANG (from 6.13 to 5.11) rapidly decreased during the first 60 days of aging and was also affected by storage temperature. The absorbance of samples at 420 nm increased during the aging process, reaching its maximum after 180 days, regardless of sample and temperature. On the other hand, the intensity of brown color in the samples increased with increasing aging period according to the results of absorbance ratio (soy sauce: 1.37 to 5.29, UHYUKJANG: 1.37 to 5.02). The L value of soy sauce increased during the aging process and was maximized after 240 days at 4$^{\circ}C$ and 180 days at 20$^{\circ}C$, but decreased thereafter. There was no significant difference in L value of UHYUKJANG, regardless of aging period and temperature. On the other hand, the b value did not reveal any significant change during aging, but the a value increased until 120 days of aging in the other samples except for UHYUKJANG at 20$^{\circ}C$. The average amount of 3DG separated from soy sauce was 5.65 mg%, and from UHYUKJANG was 3.74 mg%. These results indicated that the browning of UHYUKJANG was also caused by melanoidins produced by the reaction of amino-carbonyl during the fermentation process.