• Journal of the Korean Ceramic Society
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• v.47 no.3
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• pp.237-243
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• 2010

This research examines using Rice Husk Ash, $Cr_2O_3$ in producing the pink-red color. It studies the formation of cassiterite and malayaite crystallites, the primary factors in producing the pink-red color, in relation to the application of $Cr_2O_3$ to examine its coloring mechanism. In addition, the research intends to identify the optimum synthesizing temperature and maintaining time for crystallization of malayaite, a stable pink-red colorization factor in high temperature glaze during $Cr_2O_3$-$SnO_2$-CaO-$SiO_2$ family pigment synthesis. The optimum substituting contents is Rice Husk Ash : Quartz = 1 : 2, and the optimum temperature is suggested at $1300^{\circ}C$ for 2 h based on analysis results by XRD, FT-IR, Raman microscope, SEM and UV-vis.

• Journal of the Korean Ceramic Society
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• v.45 no.3
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• pp.172-178
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• 2008

This paper described the study of a sphene-pink pigment based on $Cr_2O_3-SnO_2-CaO-SiO_2$ system exhibits stable pink-red color at high temperature. This study is focused on the optimization of the synthesis parameter such as temperature and holding time for the formation the Malayaite crystal. Malayaite crystal is sensitively influenced by the synthesizing temperature, maintaining time and contents of substituting chromium. The crystal phases formed at different temperatures exhibits various color. The optimum temperature is suggested at $1300^{\circ}C$ for 2 h and substituting contents of Cr for Sn is 0.01 mole. The maximum substituting contents is 0.02 mole based on analysis results by XRD, FT-IR, SEM and UV-vis.

• Food Science and Biotechnology
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• v.15 no.6
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• pp.838-843
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• 2006

The chemical processes involved in the formation of green pigment in crushed garlic cloves were investigated based on the principle of pink pigmentation in macerated onions. Intact greening and non-greening garlic cloves were either left untreated or heated at $90^{\circ}C$ for 3 min to inactivate enzyme activities. First, a colorless ether soluble compound referred to as color developer reacted with glycine (among all free amino acids) in garlic to form a second compound insoluble in ether. The latter compound then reacted with formaldehyde to yield the green colored pigment. Alliinase activity was necessary for the production of color developer and for the development of green pigment. In greening garlic that had been heat treated, green pigmentation did not proceed due to the heat-inactivation of alliinase, but the addition of alliinase solution into the garlic homogenates restored the pigmentation. However, this phenomenon was not observed in non-greening garlic with or without heat treatment. Finally, the mechanism of green pigment formation in crushed garlicis similar to that of pink pigment formation in macerated onions.

• Journal of the Korean Ceramic Society
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• v.45 no.5
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• pp.268-275
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• 2008

In high temperature ceramic glazes, a stable range of pink-red colors producing $Cr_2O_3-SnO_2-CaO-SiO_2$ pigments are factored by Cassiterite and Malayaite relationship with $Cr_2O_3$. The experiment described the effect of $CrCl_3$ by adding $H_3BO_3$ as a mineralizer to increase the formation of Malayaite crystal, substituting $CrCl_3$ instead of $Cr_2O_3$ in pigment as a chromophore. Synthesized pigments were analyzed by XRD, FT-IR, Raman Spectroscop, UV and UV-vis. The result shows the differences in amount of crystal phases and oxidation state of Cr ion, which causes the color change. The melting point of $CrCl_3$ is lower than $Cr_2O_3$ which act as a mineralizer and makes the pigment synthesized in lower temperature at $1200^{\circ}C$. Holding 3 h firing at $900^{\circ}C$ where the synthesize forms shows better effect of Malayaite crystal phases and increasing engaged effect of $CrCl_3$ where the color pigmentation is more defined then in $Cr_2O_3$.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.3
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• pp.240-246
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• 1994

This study was designed to determine the optimum pigment concentration supplemented in diet and feeding periods on the pigmentation of rainbow trout(Oncorhynchus mykiss) by using acetone-extracts of ascidian tunic as a natural pigment source. The eight pigmented diets contained carotenoid of ascidian tunic extracts at concentrations of 0, 200, 400, 800, 1,600 and 3,200mg/kg of diet, carophyll pink at concentration of 800mg/kg and commercial diet. No difference in pigment concentration was found between the ascidian extracts group and the control group until 4 weeks, but the redness of muscle and integument in the 1,600, 3,200mg/kg diet and carophyll pink was increased in the dorsal and caudal areas of fish from 6 weeks of age. In the sensory panel test, fish fed the ascidian tunic extracts diet were similar to those fed the carophyll pink diet. The optimum concentration and feeding periods for pigmentation of rainbow trout was found to be ascidian tunic extracts of 1,600mg/kg diet for 8 weeks.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.98-104
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• 2017

The objective of this study was to determine the effects of short-term presalting on pink color and pigment characteristics in ground chicken breasts after cooking. Four salt levels (0%, 1%, 2%, and 3%) were presalted and stored for 0 and 3 d prior to cooking. Cooking yield was increased as salt level was increased. However, no significant differences in pH values or oxidation reduction potential (ORP) of cooked chicken breasts were observed. Cooked products with more than 2% of salt level had less redder (lower CIE $a^*$ value) on day 3 than on those on day 0. As salt level was increased to 2%, myoglobin was denatured greatly. Myoglobin denaturation was leveled off when samples had 3% of salt. With increasing salt levels, residual nitrite contents were increased while nitrosyl hemochrome contents were decreased. These results demonstrate that salt addition to a level of more than 2% to ground meat may reduce the redness of cooked products and that presalting storage longer than 3 d should be employed to develop a natural pink color of ground chicken products when less than 1% salt is added to ground chicken meat.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.4
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• pp.169-175
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• 2014

Digital ink-jet printing system has many advantages such as fast and fine printing of various images, high efficiency and low cost process. Generally digital ink-jet printing requires ceramic pigments of cyan, magenta, yellow and black with thermal and glaze stability above $1000^{\circ}C$ for the application of porcelain product design. In this study, pink-red colored $CaO-SnO_2-Cr_2O_3-SiO_2$ pigment was synthesized using solid state reaction. The synthesis conditions of $Ca(Cr,Sn)SiO_5$ pigment such as annealing temperature, amount of mineralizer and non-stoichiometric composition were optimized. Crystal structure and morphology of the obtained $Ca(Cr,Sn)SiO_5$ pigment were analyzed using XRD, SEM, PSA, FT-IR and effect of Cr substitution on the pigment color was analyzed using Uv-vis. spectrophotometer and CIE $L^*a^*b^*$ measurement.

• Journal of the Korean Ceramic Society
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• v.46 no.6
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• pp.615-620
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• 2009

The present research was performed to determine the optimal firing condition and holding time for malayaite crystal, which is responsible for the stable pink-red coloration in glaze at high temperatures, using Cr$Cl_3$ as chromophore for the synthesis of $Cr_2O_3-SnO_2-CaO-SiO_2$ system pigments. The malayaite crystal was influenced by the raw materials used for synthesis, firing temperature, and holding time. Thus there are differences in the crystal phase and in the coloration according to the condition of synthesis. When Cr$Cl_3$ was used as chromophore, the pigment could be synthesized at lower temperatures, because Cr$Cl_3$ melts at $1500{^{\circ}C}$, which is much lower than the temperature at which $Cr_2O_3$ melts (higher than $2435{^{\circ}C}$). And the employed Cr ion showed a change in oxidation state. When a mineralizer was used to improve the employment of malayaite and the Cr ion, and the low temperature was maintained at which the malayaite crystal is produced, the production of malayaite crystal was promoted and the employment of chromophore was also promoted in the oxidation state of Cr (IV). The results of the experiment showed that the optimal firing condition was 18 h of holding time at $800{^{\circ}C}$, using Cr$Cl_3$ as chromophore, followed by 2 h at the raised temperature of $1150{^{\circ}C}$. The change in coloration of the Cr (IV) employed by malayaite showed a very rich color of red. Thus it was possible to effectively synthesize sphene-pink pigments with more red tint at a low temperature.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.3
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• pp.357-368
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• 1996

To utilize the ascidian tunic as a natural pigment and dietary sources for rainbow trout (Oncorhynchus mykiss), juvenile were fed on experimental diets containing enzymatic hydrolysates of ascidian tunic treated with three commercial mined enzymes (ultrazyme, cellulase, viscozyme) for 12 weeks. From the results of feeding experiment, similar growth rate was checked in the enzymatic hydrolysis group compared with control, and those were a higher than of ascidian tunic powder group. The total acetone extractable pigment in muscle of the enzymatic hydrolysates group was lower than that of the ascidian extracts group and carophyll pink group until 8 weeks, but the level of those pigment of the enzymatic hydrolysates was similar to the ascidian extracts and carophyll pink group after 12 weeks. The lipid content was increased with the pigment concentration in the all experimental group. But the ascidian tunic pigment did not influence on the composition of the fatty acids in the muscle and liver. From the consideration of results for pigmentation, the enzymatic hydrolysates of ascidian tunic were suitable for both a natural pigment and dietary protein and carbohydrates sources as a substitute synthetic pigment for aquaculture use.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.417-430
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• 2018

This study was conducted to determine the effects of NaCl concentration and cooking temperature on the color and pigment characteristics of presalted ground chicken breasts. Four treatments with different salt concentrations (0%, 1%, 2%, and 3%) were prepared and stored for 7 d prior to cooking. Each sample was cooked to four endpoint temperatures ($70^{\circ}C$, $75^{\circ}C$, $80^{\circ}C$, and $85^{\circ}C$). The salt concentration affected the color and pigment properties of the cooked ground chicken breasts. As the salt concentration increased, the cooking yield and residual nitrite content also increased. However, the samples with 1%, 2%, and 3% NaCl showed similar nitrosyl hemochrome and total pigment contents. Among the products containing salt, the samples with 3% NaCl showed the lowest percentage myoglobin denaturation (PMD) and the lowest CIE $a^*$ values. The cooking temperature had limited effects on the pigment properties of cooked ground chicken breasts. The oxidation-reduction potential and residual nitrite contents increased with cooking temperature, while the PMD, nitrosyl hemochrome, total pigment contents and CIE $a^*$ values were similar in the samples cooked at different temperatures. These results indicated that the addition of up to 2% salt to ground chicken breasts and storage for 7 d could cause the pink color defect of cooked products. However, the addition of 3% NaCl could reduce the redness of the cooked products.