• Korean Journal of Agricultural Science
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• v.38 no.1
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• pp.79-86
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• 2011

The contents of free amino acid in cabbage cultivars originated from China and Korea were measured to determine the quality for taste and nutrition. The experimental variables were season (spring-sowing and fall-sowing), leaf position (inside and outside), and the cabbage color (green and red). Eighteen free amino acids were detected at the range of 0-38 mg/g dry weight. The most abundant amino acid was serine(0-128 mg/g). Alanine, aspartate, glutamate, asparagine, histidine, and proline were relatively rich at 2-12 mg/g dry weight. Glycine were significantly increased in spring-sowing cabbages by 2-fold but proline was reversely decreased by 7-fold. The inside parts of cabbages contained significantly more alanine, glutamate, glycine, isoleucine, serine, and valine than the outside ones. The higher contents of isolecuine, leucine, proline, and valine were observed in the red cabbages than the green ones. The significant cross effects of season-color and position-color were also observed, indicating the red and the green cabbages were differently affected by season and tissue position.

• Food Science and Preservation
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• v.20 no.6
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• pp.805-809
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• 2013

This study was carried out to investigate the effects and characteristics of sausages with red yeast rice added, particularly the Monascus purpureus KFRI 1134 strains, and to decide the optimal quantity of red yeast rice used. The additional rate of red yeast rice which has been used as a material for reducing nitrite, a coupler in meat products were 0, 1, 3, and 5% (w/w). In terms of the effects of the red yeast rice on the color, texture properties, and sensory characteristics of the sausages, the optimal temperature at which color stability was shown was below $100^{\circ}C$, and the addition of 1% red yeast rice resulted in a distinctly attractive color and increasingly improved the red color in the UV-visual Spectrophotometer analysis. However, the addition of over 1% (w/w) resulted in an unattractive color. The red colors also had strong heat stability. The texture properties and taste of the sausages were not affected by the red yeast rice.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.410-413
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• 1991

Prefried chicken patties were irradiated at dose levels of 0, 2, and 4 kGy using $Co^{60}$ source and stored at $3{\pm}1^{\circ}C$ and $-10{\pm}1^{\circ}C$, separately for the evaluation of color and sensory characteristics. Irradiation dose of 4 kGy slightly darkened the internal color of chicken patties. Except for the internal portion of the frozen samples, an increase (p<0.05) in Hunter 'L' values was observed for both the surface and interior of patties during storage. Upon refrigerated storage, Hunter 'a' values, both on the surface and internally, decreased as the storage period progressed. Only storage period affected (p<0.05) the Hunter 'b' values of patty surfaces and interiors. No difference (p<0.05) in odor, taste, color, and texture of the patties was observed for irradiation dose and storage period as evaluated by triangle tests except between 2 kGy and 4 kGy irradiated samples before forzen storage.

• Food Science and Preservation
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• v.9 no.3
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• pp.345-350
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• 2002

This study was carried out to determine the effect of gamma irradiated Puerariae radix extract on color removal, antioxidative, DPPH radical scavenging and antimicrobial efftcts. Puerariae radix were extracted with methanol and acetone and irrdiated 10, 20 and 30 kGy with gamma ray. Hunter color L-value increased by irrdiation in a dose dependent manner, resulting in brighter color. But a and b values decreased by irradiation in a dose dependent manner. Antioxidant activities of the Puerariae radix extract in soybean oil emulsion were higher in methanol extract than acetone extract. Scavenging effect of Puerariae radix extracts on DPPH radical with methanol was not changed by irradiation but acetone decreased Acetone extract from Puerariae radix showed antimicrobial activities in B. subtilis, B, natto, B, megaterium S, aureus, Sal, typhymurium and E. coli methanol extract also had the antimicrobial activities but weaker for Sal. typhymurium and E. coli. Results suggested that Puerariae radix extracts have a potential as a natural food preservatives and cosmetic raw material.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.1
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• pp.137-142
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• 2003

This study was carried out to examine the effects of gamma irradiation on the color removal, antioxidation, DPPH radical scavenger, and antimicrobial activity of Schizandra fructus extracts by different solvents. Schizandra fructus was extracted by hot water, ethanol, acetone and methanol, and the extracts were irradiated 10, 20 and 30 kGy with gamma rays. Hunter color L-value was increased by irradiation in a dose-dependent manner, resulting in brighter color for all solvents used. The a and b values were decreased by irradiation in a dose-dependent manner. Antioxidant activity of the ethanol extract of Schizandra fructus against soybean oil was the highest. The free radical scavenging activity was the strongest in hot water extract. All solvent extracts from Schizandra fructus had the strongest antimicrobial activities to B. subtilis, B. natto, B megaterium, S. aureus, Sal. typhymurium and E. coli. These results suggested that Schizandra fructus extracts have a strong potential as natural food preservatives and cosmetic raw materials. Furthermore, irradiation may not influence adversely on biological activites of the extracts when irradiated up to 30 kGy.

• Food Science and Preservation
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• v.17 no.6
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• pp.847-852
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• 2010

The anthocyanin pigment composition and color of several grape cultivars including Campbell Early, Muscat Bailey A, Kyoho (black berries), and North Red (red berries), were investigated. Twelve types of anthocyanins were identified in these cultivars by LC-MS. Black-colored cultivars, especially Muscat Bailey A, contained the widest range of anthocyanins, whereas the anthocyanin composition of North Red, the red-colored cultivar, was relatively simple. Anthocyanins extracted from the skin of berries were red in color at low pH, regardless of the origin of the extract. At higher pH, however, various colors, including blue, violet, brown, and black, were evident, depending on the cultivar. Differences in color expression among cultivars may be related to variations in the types and amounts of anthocyanidins synthesized, from which anthocyanin pigments are derived. The colors expressed by anthocyanin pigments were strong and diverse even at low concentrations. Therefore, anthocyanins extracted from grapes may be useful as natural food colorants.

• Food Science of Animal Resources
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• v.30 no.2
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• pp.171-178
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• 2010

The objective of this study was to compare the quality characteristics of chicken breast and thigh meat from North Korean native chickens (NKNC), South Korean native chickens (SKNC, woorimotdak), and commercial broilers (CB). NKNC thigh meat had a higher crude protein content than CB. In addition, the breasts of NKNC and CB had higher pH values than that of SKNC, but the cooking loss was higher in NKNC. The surface color of the breast and thigh meat of NKNC was darker and redder than that of SKNC and CB. The total collagen content of the breast and thigh muscles was the highest in NKNC, followed by SKNC and CB. A similar trend occurred with breast meat hardness. The content of arachidonic and docosahexaenoic acids was higher in both the breast and thigh muscles of NKNC than in those of the other groups, while the concentrations of linoleic and linolenic acids were higher only in thigh meat. Sensory evaluation did not show any differences among the three different strains of chicken except for the meat color. Sensory panelists preferred thigh meat from SKNC and CB to that of NKNC due to the strong dark color of the NKNC. Based on these results, NKNC had harder breasts based on texture, as well as a darker surface color and higher composition of long chain polyunsaturated fatty acids than CB. The quality characteristics of SKNC tested in this study were intermediate between NKNC and CB; however, SKNC may have a better chance of acceptance by Korean consumers due to the undesirable color of NKNC.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.5
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• pp.784-790
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• 2014

This study was designed to establish the shelf-life of sea tangle drink. Quality changes, including pH, total acidity, color, sensory evaluation, total aerobic bacteria, and coliform, were measured periodically in sea tangle drink kept at 15, 25, and $37^{\circ}C$ for 8 months. The pH level and total acidity did not remarkably change during the storage period regardless of storage temperature. In terms of color, lightness did not change during the storage period, whereas redness decreased. Yellowness did not change at $15^{\circ}C$ during the storage period, although it increased at 25 and $37^{\circ}C$ at 8 months. Color difference (${\Delta}E$) value was the lowest at $15^{\circ}C$ (12.14), followed by $25^{\circ}C$ (12.57) and $37^{\circ}C$ (14.43). During the storage period, total aerobic bacteria and coliform were not detected. There were no changes in appearance, smell, taste, texture, and overall acceptability of sea tangle drink (not exceeding 3 points) throughout the entire storage period. By using correlation coefficients, color value was selected as an indicating parameter for the shelf-life establishment of sea tangle drink. Based on the forecasted distribution day by annual temperature, the shelf-life of sea tangle drink based on color with the highest correlation coefficient was predicted as 27.10 months.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.6
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• pp.780-785
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• 2006

The composition analysis of various radish (Rapharnus sativus L.) leaves and the effects of drying condition on the quality characteristics of hot-air dried radish leaves were carried out by a response surface methodology. Independent variables put in drying temperature $(X_1)$ and drying time $(X_2)$, dependent variables put in color, calcium, iron, vitamin, etc. In the proximate composition of radish leaves by varieties, there were no significant differences in the ash, protein, lipid, calcium and iron content of samples, but there were significant differences in the vitamins, chlorophyll and color value of samples. The quality characteristics on dried radish leaves by central composite design, it was significant value on the moisture content, chlorophyll and color value according to drying temperature and drying times. But there were no significant differences in the contents of calcium $(31.41{\sim}35.80\;mg/g,\;dry\;base)$ and iron $(0.21{\sim}0.29\;mg/g\;dry\;base)$. The multiplex regression coefficients analysis were calculated with independent variables $(X_1,\;X_2)$ and dependent variables (moisture, chlorophyll, color value). The calculated coefficient correlations for the each samples were $R^2>0.97$. The effects of drying temperature were greater than drying time in the total chlorophyll content changes of radish leaves. Based on the present study, the optimum drying condition for the lowest color changes and effective reduction of moisture of radish leaves were expected to be $5{\sim}6$ hours at $70^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.35 no.1
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• pp.23-27
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• 2003

The effects of temperature and pH on color deterioration of anthocyanin in Schizandra fruit (Schizandra chinensis fructus) were determined with temperature range of $80{\sim}100^{\circ}C$ and pH range of $2.0{\sim}5.0$. Browning index was used as an index of color deterioration of crude anthocyanin extract from Schizandra fruit. As pH of crude anthocyanin extract was increased, color deterioration was accelerated, showing pH-dependency of thermal stability of anthocyanin extract from Schizandra fruit. Anthocyanin degradation could be modeled as a second-order rate reaction, with rate of $3.2{\times}10^{-3}\;h^{-1}\;(pH\;2.0){\sim}4.1{\times}10^{-3}\;h^{-1}\;(pH\;5.0)\;at\;100^{\circ}C$. Temperature dependence of deterioration was described by the Arrhenius relationship. Activation energies for pH $2.0{\sim}5.0$ ranged from $24.87{\sim}42.54\;kJ/mol^{-1}$.