• The Korean Journal of Food And Nutrition
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• v.21 no.4
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• pp.499-509
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• 2008

The purpose of this study was to investigate the changes in physicochemical and sensory properties of raw fruits during washing and chlorine treatments. Strawberry and banana were pre-prepared at different concentration of chlorinated water(0 ppm, 50 ppm and 100 ppm), immersion time(3 min and 5 min), and number of post-rinsing(1 time, 2 times and 3 times). The physicochemical properties such as pH, sugar contents, residual chlorine contents, color values and hardness of the fruits were analyzed, and the sensory quality were evaluated throughout the sterilization treatment process. After washing strawberry with 100 ppm chlorinated water and 3 times of post-rinsing, pH and residual chlorine contents were showed a little difference, while sugar contents, hardness, and color values(L, a and b) were reduced. In case of banana, pH, sugar contents and residual chlorine contents were not affected, and hardness and L color value were reduced. However, a and b color values of banana were gradually increased as the development of brown discoloration. Sensory properties of the samples were affected by the chlorine sterilization treatment. In overall acceptance, strawberry and banana treated with 100 ppm chlorinated water showed the lowest scores among treatments. Therefore it could be suggested that the application of 50 ppm chlorinated water for $3{\sim}5$ minutes with over 3 times of post-rinsing was the effective pre-preparation method without affecting the quality of the fruits.

• Journal of the East Asian Society of Dietary Life
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• v.25 no.4
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• pp.660-666
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• 2015

Natural food colorant are widely used to satisfy consumer preferences. Anthocyanins are red, blue and purple natural pigments. Purple-fleshed sweet potato (PSP) contains large quantities of anthocyanins. The aims of this work were i) to investigate the influence of sugars on the purple color of PSP jam and ii) to optimize the ratio of ingredients for sensory characteristics of PSP jam. Korean PSP variety "Sinjami" was used for the preparation of jam. The jams were prepared with various sugar contents (0, 20, 30, 40 and 50% total weight) consisting of steamed purple-fleshed sweet potato, water, lemon juice and apple juice. With increasing sugar contents, lightness (L) and redness (a) of PSP jams decreased while yellowness (b) increased, indicating that anthocyanins were degraded and/or brown pigments were formed due to high sugar content under heat treatment. Hardness, springiness, chewiness and cohesiveness showed significant differences among PSP jams with various sugar contents. In sensory evaluation, addition of sugar significantly increased scores for color and texture as compared to control samples. The color, texture and preference results indicate an optimal sugar content of 40% total ingredient weight for PSP jam.

• Proceedings of the Korea Hospitality Industry Research Society Conference
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• 2003.05a
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• pp.51-58
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• 2003

The autoclave method and the traditional cooking method are compared for nutrients, mineral, color difference, viscosity, reducing sugar and amino nitrogen content of brown stock. For protein and amino nitrogen contents, the autoclave cooking method is better than the traditional cooking method. Also, reducing sugar content is increased by the autoclave cooking method. Since the color of brown sauce is related with reducing sugar content, the autoclave cooking method is more effective than the traditional cooking method for the color of brown sauce. Since the autoclave method can reduce the cooking time without the loss of quality in brown stock, the traditional method can be substituted by this new method.

• Journal of the Korean Society of Tobacco Science
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• v.28 no.1
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• pp.1-8
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• 2006

To get the information of flue-cured leaf, the chemical constituents, quality indices, leaf color and the effects of climatic factors on the physicochemical properties of leaf produced from 2000 to 2004 crop years at 6 growing areas were analysed. The average leaf chemical contents for 5 years were as follows ; nicotine 2.22%, total sugar 28.0%, total nitrogen 1.89%, ether extracts 6.37% and chlorine 0.38%. The nicotine and total nitrogen contents were low while the total sugar were high as compared with KT&G recommended contents(nicotine ; $2.5{\sim}3.0%$, total nitrogen; $2.0{\sim}2.5%$, total sugar ; below 25.0%). The variations of physicochemical properties among crop years were high while those of growing areas relatively low. The nicotine content of leaf was negatively correlated to the rainfalls in June and July sugar content was negatively correlated to the average air temperature in June and July according to crop years. The orange colored leaves were produced under the drought and long sunshine weather condition while the lemon colored leaves were produced under the contrary condition according to crop years. Blending the different crop year's leaves in the proper way may be beneficial to produce of uniform and consistent cigarettes. It is considered that the increasing of nitrogen fertilizer or improving of nitrogen uptake may be available to increase the nicotine and nitrogen and decrease the total sugar contents of flue-cured leaf tobacco.

• Applied Biological Chemistry
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• v.35 no.6
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• pp.437-442
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• 1992

In order to develop color of potato chip made from Superior variety and Irish Cobbler variety, various conditions on NaCl and $CaCl_2$ contents, heat treatment and soaking time were applied. The content of reducing sugar decreased by $30{\sim}40%$ in blanching without NaCl and $CaCl_2$. In NaCl soaking case, reducing sugar content decreased by $15{\sim}30%$, however, partial colorization was appeared that the sample turned to brown. In the sample that were soaking in NaCl solution and heat treated, reduction of reducing sugar was 40% and desirable time for heat treatment was 5 min and 7 min. In the sample treated $CaCl_2$ solution, reduction of reducing sugar was $25{\sim}30%$ and then color was not acceptable. In the sample soaking $CaCl_2$ solution and heat treated, reducing sugar content rapidly by 50% and the color development was the most ideal.

• Food Science and Preservation
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• v.3 no.1
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• pp.23-32
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• 1996

Total carotenoid contents, color values and spectrum characterization in the range of UV of fruit juice and organic acid and free sugar contents determined by HPLC were investigated on 10 varieties of Cheju citrus fruits. Carotenoid contents of juice were 0.47-9.20$\mu\textrm{g}$/ml which showed higher with Dangyooja while showed lowest content with Meiwa Kumquat. Lightness (L) of juice was highest in Meiwa Kumquat, and in the order of Sankyool, Navel orange and Hungjin. Redness(a) and yellowness(b) were in the order of Dangyooja, Natsudaidai, Sambokam and Kinkoji. The maximum absorption wavelengths if citrus Juices were variable at 269.5-285.5nm according to varieties and it was observed that were changed by mixing with Juices of other varieties. Major organic acids of citrus juice were citric and malic acid, and citric acid was 64.4-95.1% of total organic acids. Ascorbic acid was high in Navel orange, Sudachi and Dangyooja, and low in Meiwa Kumquat and Hungjin. Major free sugars were sucrose, glucose and fructose. Sucrose was 49.2-75.2% of total free sugars, and high in Sankyool and Meiwa Kumquat. Glucose and fructose were high in Meiwa Kumquat and Navel Orange.

• Journal of the Korean Society of Food Culture
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• v.32 no.1
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• pp.58-65
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• 2017

This study was conducted to optimize the conditions of a sweet rice paste as a replacement of red bean paste recipe using the central composite design of response surface methodology (RSM). Ten experimental recipes with two reference points (rice flour and sugar), were selected, and the physical and sensory characteristics of a sweet rice paste were measured. In the Rapid Visco Analyzer test, breakdown value was the highest in rice flour (105.73 RVU). Sweetness significantly increased with addition of sugar contents (p<0.0002) and viscosity increased with addition of rice flour contents (p<0.0185). Moisture contents decreased with increasing contents of rice flour and sugar, whereas yellowness and redness tend to increase. In the sensory evaluation test, quadratic models for color (p<0.01865), sweetness (p<0.0399), thickness (p<0.0073), and overall acceptability (p<0.0249) were approved as independent for the rice flour and sugar contents. In conclusion, the optimal mixing ratio of sweet rice paste was determined to be 45.38 g of rice flour and 77.95 g of sugar.

• Journal of Ginseng Research
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• v.17 no.3
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• pp.228-231
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• 1993

Physicochemival properties of ginseng roasted at 170 to $250^{\circ}C$ were investigated. Soluble solid contents in roast ginseng increased until $200^{\circ}C$, but decreased at higher temperature than $200^{\circ}C$. Contents of reducing sugar and protein were decreased and pH values were dropped, while optical density, acidic polysaccharide contents, precursor of brown pigments and hydrogen donating activities by DPPH were increased according to increasing in roast temperatures. The color distribution of roast ginseng expressed as Hunter L, a and b values demonstrated that lower L values and higher a values were observed according to higher temperature, but b values were almost not changed.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1526-1526
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• 2001

To improve the accuracy of sweetness sensor in automated sorting operations, it is necessary to clarify unevenness of the sugar content distribution within fruits. And it is expected that the technique to evaluate the content distribution in fruits contribute to the development of the near-infrared (NIR) imaging spectroscopy. Sugiyama (1999) had succeeded to visualize the distribution of the sugar content on the surface of a half-cut green fresh melon. However, this method cannot be applied to red flesh melons because it depends on information of the absorption band of chlorophyll (676 nm), which is affected by the color of the fresh. The objective of this study was to develop the universal visualization method depends on the absorption band of sugar, which can be applied to various kinds of melons and other fruits. The relationship between the sugar contents and absorption spectra of both green and red fresh melons were investigated by using a NIR spectrometer to determine the absorption band of sugar. The combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm was highly correlated with the sugar contents. The wavelength of 902 nm is attributed to the absorption band of sugar. A cooled charge-coupled device (CCD) imaging camera which has 16 bit (65536 steps) A/D resolution was equipped with rotating band-pass filter wheel and used to capture the spectral absorption images of the flesh of a vertically half-cut red fresh melon. The advantage of the high A/D resolution in this research is that each pixel of the CCD is expected to function as a detector of the NIR spectrometer for quantitative analysis. Images at 846 nm, 874 nm, 902 nm and 930 nm were acquired using this CCD camera. Then the 2$\^$nd/ derivative absorbances at 902 nm and 874 nm at each pixel were calculated using these four images. On the other hand, parts of the same melon were extracted for capturing the images and squeezed for the measurement of sugar content. Then the calibration curve between the combination of 2$\^$nd/ derivative absorbances at 902 nm and 874 nm and sugar content was developed. The calibration method based on NIR spectroscopy techniques was applied to each pixel of the images to convert the 2$\^$nd/ derivative absorbances into the Brix sugar content. Mapping the sugar content value of each pixel with linear color scale, the distribution of the sugar content was visualized. As a result of the visualization, it was quantitatively confirmed that the Brix sugar contents are low at the near of the skin and become higher towards the seeds. This result suggests that the visualization technique by the NIR imaging spectroscopy could become a new useful method fer quality evaluation of melons.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.1
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• pp.128-136
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• 2015

This study investigated the effects of low-dose electron beam irradiation treatment on physicochemical and sensorial properties of imported navel oranges during storage at $3^{\circ}C$ for 45 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, and changes in their color values, hardness, Brix/acid ratio, total sugar contents, reducing sugar contents, vitamin C contents, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color values, Brix/acid ratio, total sugar contents, total reducing sugar contents, and vitamin C contents. Hardness of irradiated sample at 1 kGy decreased significantly in the early storage period, but the difference between non-irradiated and irradiated samples decreased again at the end of storage. For the sensory evaluation, scores of color, sweetness, flavor, and overall acceptability decreased as irradiation dose and storage period increased. Samples irradiated at over 0.8 kGy showed low preference in all scores except color. These results suggest that electron beam irradiation below 0.6 kGy does not affect physicochemical and sensory properties; thus, electron beam irradiation up to 0.6 kGy in imported navel oranges is optimum for minimizing quality changes and disinfestation treatment simultaneously.