• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.453-458
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• 1994

43 Kinds of physicochemical characteristics of koji kochujang prepared by a standardized industrial process were determined and analyzed statistically during storage for 105 days at $37^{\circ}C$. The characteristics which showed significant correlation with storage period after preparation of kochujang were 12 items, which included sensory preference for flavor and taste, Hunter tristimulus values($L,\;a,\;b,\;{\{\delta}E$), HMF, capsanthin, formol nitrogen, threonine, water and water activity. Seven of the items were related with color attributes of kochujang. Especially, tristimulus values showed significant correlation with sensory preference for color of kochujang. In this regard, tristimulus values should be recommended as new quality indices of national standard for industry-produced koji kochujang. Means and standard deviations of tristimulus values of 27 kinds of industry-produced koji kochujang in the market were $28.21{\pm}1.48,\;a=9.37{\pm}2.54,\;b=4.35{\pm}2.19\;and\;{\delta}E=30.09{\pm}2.42.$.

• Korean Journal of Food Science and Technology
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• v.27 no.4
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• pp.525-531
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• 1995

Three quality factors of bread during baking process were measured to develop neural network models for bread baking process. Firstly, volume and browning changes during bread baking process were measured using image processing technique and temperature changes inside the bread during process were measured by K-type thermocouples. Relationships among them showed nonlinearity. Secondly, multilayer perception structure with error back propagation learning was used to construct neural network models. Three neural network models for volume, browning, and bread temperature were developed respectively. Developed models showed good performance with predictive error of 4.62% for volume and browning changes after 30 seconds, 7.38% for volume and browning changes after 2 minutes, and 1.09% for temperature change inside the bread respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.355-360
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• 2002

Effect of additive on color reversion of green tea extract, whose undesirable color had been removed by irradiation, was studied during storage. Hunter color L-vague of irradiated sample was significantly higher than that of nonirradiated control. The color of green tea extract with butylated hydroxyanisole (BHA) did not differ from that of the control but the green tea extract with ascorbic acid had higher L-value than the control during the whole storage (p<0.05), However, the sample irradiated at 20 kGy showed a faster color reversion than the sample with 5 or 10 kGy of irradiation. Hunter color a-values were decreased by irradiation and the sample with ascorbic acid showed the lowest. The result of Hunter color b-value was also similar to that of Hunter color a-value, indicating that when the irradiation technology is used for color improvement of green tea extract, the ascorbic acid can be added to minimize color reversion of the extract during delivery or storage.

• Korean Journal of Food Science and Technology
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• v.13 no.4
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• pp.334-339
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• 1981

Surface color, water extract color and soluble solids of the roasted barley resulted from the various roasting conditions were determined to establish the optimum roasting conditions. The correlation coefficients between the surface color of the roasted barley and its ground was in the range from 0.957 to 0.994, and which showed the internal color being well represented that of surface of the roasted grain. The degree of roasting was determined maim by the roasting temperature, rather than by the total heat energy input during roasting. The maximum yield of the water soluble solids was 68% and obtained from the barley roasted at $232^{\circ}C$ for 25 minutes. The readings of Y-value of the roasted whole barley was a good index to judge and control the degree of roasting.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.636-641
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• 2006

Jeolpyun with different amounts of added ramie (Ramie Jeolpyun) was prepared and the quality characteristics were examined. Texture profile analysis, Hunters color and total microbial counts were carried out during storage for 4 days. Sensory evaluation was carried out during storage for 2 days. The L value of Jeolpyun with 0% added ramie was one of the highest in the sample and increased with increasing storage time. In texture profile analysis, hardness, chewiness, gumminess were increased with increasing storage time. The hardness of Ramie Jeolpyun with 80% added ramie was one of the lowest in the samples. The total microbial counts of Ramie Jeolpyun were increased during storage. The results of sensory evaluation showed that Ramie Jeolpyun with 60% and 80% added ramie had a high score in color, flavor and softness.

• Korean journal of food and cookery science
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• v.5 no.1
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• pp.15-21
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• 1989

These experiments were carried out to study the factors affecting quality and textural characteristics in the preparation of artificial gluten meat (AGM). Effects of amounts of ingredients on properties of AGM were summarized as follows: 1. The more amounts of water increased, the higher L and b values became, and AGM, therefore, became bright and yellow in color. The more increased the amount of water, the more decreased shear force, hardness and chewiness, but the water holding capacity increased. The 100% of water added sample approached to raw beef in L value, $\Delta$0E, hardness and chewiness. 2. The mixing ratio of walunt and com oil more affected on color than on texture, and the proper ratio was 30% of walunt and 10% of oil. 3. In the case of interactions of oil and water, water amounts affected more on color, shear force, chewiness and the water holding capacity than on oil. AGM mixed with the ratio of 10% of oil and 100% of water approached to raw beef.

• Korean Journal of Food Science and Technology
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• v.46 no.2
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• pp.173-179
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• 2014

The fermentation characteristics of ice wines made from freeze-dried Muscat Bailey A grapes were determined. Muscat Bailey A grapes were concentrated to 34.8 and $40.8^{\circ}Bx$ by freeze drying and were then fermented. The content of reducing sugar was 0.3% in conventional wine after fermentation, but was 21.5 and 23.9% in ice wines at 34 and $40^{\circ}Bx$, respectively. The content of alcohol was 9.6% in conventional wine but was 10.3 and 10.6% in ice wines at 34 and $40^{\circ}Bx$, respectively. It was observed that the red and violet colors of ice wines at 34 and $40^{\circ}Bx$ became dominant compared to the controls. In sensory evaluation studies, ice wines at 34 and $40^{\circ}Bx$ showed higher intensities in color, flavor, and overall preference.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1881-1888
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• 2014

Pre-thermal treatment is important to minimize quality changes during main cooking or storage. In this study, to optimize pre-thermal treatment of carrots, three types of pre-thermal treatments were applied to carrots and quality changes such as physicochemical, nutritional, or sensory properties were observed. Washed and sliced carrots were thermally treated by hot-water immersion ($100^{\circ}C$, 1~10 min), steaming ($100^{\circ}C$, 1~10 min), and stir-frying with oil (10~80 sec). Carrot tissue was maintained until 2 min hot-water immersion or steaming, and they were damaged by just 30 sec of stir-frying. Color and hardness were significantly affected by treatment time and temperature. Color was completely changed after 5 min and 7 min by hot-water and steam treatments, respectively. Hardness decreased to 44% compared with fresh carrot (4,500 g) after 1 min, 3 min, and 20 sec of hot-water, steam, and stir-frying, respectively. For nutritional changes, ascorbic acid, organic acid, and peroxide activity were reduced by all treatments compared with fresh carrot. Especially, succinic acid was dramatically reduced by hot-water treatment. Otherwise, free sugar contents were increased with greater treatment time in all samples. In this study, pre-thermal treatment of carrot was optimal at 2 min steaming treatment.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.1
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• pp.32-38
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• 2002

The characteristics of blown color of Korean traditional soy sauces under different processing conditions were investigated in this research. As for meju type, traditional and modified mejus were used. The samples were produced from four levels of aging time. 0 day, 60 days, 120 days and 180 days in both clay jar and glass jar. Color intensity of soy sauce was probed with different mothods. In terms of colorcharacteristics, the absorbance at 420 nm seemed to reflect the brown color intensity of soy sauces. UV-VIS spectra of the soy sauce with traditional meiu revealed that the absorbance at 235 nm was produced during the soaking period whereas that at 410 nm was created during the aging process and only round in the spectra of soy sauce aged for 180 days. As for the soy sauce with modified meiu, the maximum absorbance was focused at 235 nm which were prepared during soaking period.

• Korean Journal of Food Science and Technology
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• v.18 no.4
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• pp.306-312
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• 1986

Color changes of a mixture of 0.8 M glucose, fructose or sucrose and 0.8 M glycine were evaluated by Hunter 'L', 'a', 'b' values during Maillard reaction at the temperature range of $70^{\circ}-100^{\circ}C$. The results suggested the reaction to be devided into three stages. In initial reaction the 'L' and 'a' values decreased slowely, and 'b' rapidly increased to maximum, which were followed by a rapid decrease in 'L' and 'b' and rapid increase in 'a' values at intermediate stage. At final reaction period the both 'L' and 'b' were slowed down in their reduction rate while 'a' decreased rapidly from its maximum point. All of the Hunter values were reached to nea. zero. Linear equations, which can be used for prediction of cole. change in Maillared reaction, of $1/\sqrt{(L_t-L_{\circ})^2\;+\;(a_t-a_{\circ})^2\;+\;(b_t-b_{\circ})^2}\;=\;a(1/t)\;+\;b$ for Hunter values and $1/\sqrt{X\;+\;Y\;+Z}\;=\;a(1/t)\;+\;b$ for CIE tristimulus values were found to have a very high correlation coefficient. Relationships between 'L' and 'a', 'L' and 'b' and 'a' and 'b' were also graphcally compared.