• Journal of Food Hygiene and Safety
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• v.20 no.2
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• pp.73-76
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• 2005

Center for Food Standard Evaluation, Korea Food and Drug AdministrationThis study was performed to compare analytical methods of nine synthetic food colors and six food color lakes in Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA. The experimental protocol of this study consists of three parts: titration method with titanium chloride, gravimetric and spectrophotometric method. To measure the total contents of food colors, Korea and Japan used titration method with titanium chloride, USA used the average value of titration method with titanium chloride equipped with Kipp generator and spectrophotometric method. Also, JECFA used titration method with titanium chloride equipped with KiPP generator. However, All the low organizations used gravimetric method to measure the total content of coloring matter on Food Red No.3. Although all organizations use various methods for analysis of coloring matters, total contents of coloring matter on food colors tested fell into the standard showing $85.08-96.40\%$ in synthetic food colors and $10.00-36.86\%$ in food color lakes.

• Journal of the Korean Society of Food Culture
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• v.7 no.2
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• pp.105-112
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• 1992

The general properties(size, shape, fruit constituents) of ten different varieties of dried red pepper and the proximate chemical composition, carotenoids content and Hunter color values of their powders were examined in order to establish an objective instrumental method to evaluate the consumer acceptability of red pepper powder. The results of instrumentally measured color values were compared with the sensory acceptability data obtained from 100 housewives in Korea. Red carotenoid consisted of 68-85% of total carotenoids, while ${\beta}-carotene$ content showed close relationship with the sensory color preference. The values of Hunter color system, L,a,b and axL, showed significant relationships with the sensory color preference. Especially, axL value had close relationship with both color preference and pungency intensity of red pepper. Therefore, we suggest the consumer acceptability of red pepper powder can be determined instrumentally by axL value of colorimeter. Sensory acceptability=0.02001(axL)-12.5774

• Preventive Nutrition and Food Science
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• v.13 no.4
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• pp.306-312
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• 2008

This study investigated the influence of pH on the color development of melanoidins formed from amino acid enantiomer model systems. For this, the color development was evaluated by measuring browning at 420 nm and color measurements by spectrophotometry and colorimetry. The browning and browning index showed no difference according to the type of amino acid enantiomers, while that formed from the D-Asn system was the only difference according to pH level. The tristimulus value of melanoidins formed from all model systems was located on a dominant wavelength of 475 nm, the blue zone of the diagram. In addition, the $L^*$, $a^*$, $b^*$, $C^*_{ab}$ values, and ${\Delta}E^*$ index on the basis of the type of amino acid enantiomers, the differences were markedly found at pH 4.0. At pH 7.0, significantly differences were found in the $L^*$, $a^*$, $b^*$ values, and ${\Delta}E^*$ index and not in the case of the lysine enantiomers. In addition, at pH 10.0, the differences were found in the $a^*$ and $b^*$ values from the lysine enantiomers and $C^*_{ab}$ value from the asparagine enantiomers. Therefore, the color development of melanoidins was influenced by the type of amino acid enantiomers and pH levels. Especially, it is thought that the $a^*$ and $b^*$ values can be used to explain the differences among the amino acid enantiomers in the color development of melanoidins.

• Journal of the Korean Society of Food Culture
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• v.12 no.2
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• pp.195-200
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• 1997

The purposes of this study were to investigate the Maillard reactions of some oligosaccharides with lysine and the antioxidative effects of the ethanol extracts from their reaction mixtures on the soybean oil. The Maillard reactions were carried out of 2% oligosaccharides such as palatinose (PN), fructooligosaccharide (FO), isomaltooligosaccharide (IMO) with 2% lysine (L) for 24 hours heating at 60, 80, $100^{\circ}C$. The color intensity of Maillard reaction mixtures were determined by UV-VIS spectrophotometer upon reaction time and temperature. And the antioxidative effects on the soybean oil of each ethanol extract from Maillard reaction mixture of each oligosaccharide were measured by peroxide value (POV). POV's of soybean oil including reaction extracts were determined regularly every 2 days during 20 days storaged at $60{\pm}1^{\circ}C$. The results were obtained as follows: 1. The color intensity of the Maillard reaction mixtures were raised highly as the browning temperature and time increased. The color intensity of PN L browning mixture was the highest. The order of high color intensity at $100^{\circ}C$ was PN L>FO L>Glu L>IMO L. 2. Comparing the antioxidative effect of Maillard reaction product (at $100^{\circ}C$, for 12 hours) of each oligosaccharide to that of BHT and TBHQ, the order of high antioxidative effect was TBHQ>IMO L>BHT>Glu L>PN L>FO L. 3. From these results, it was known that PN L shown as high brown color intensity was appeared low antioxidative effect, while IMO L shown as low brown color intensity was appeared high antioxidative effect. So, it was recognized that there was no relation between brown color intensity and antioxidative effect.

• Korean Journal of Food Science and Technology
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• v.21 no.2
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• pp.294-299
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• 1989

The quality of dehydrated instant rice produced by a few selected processing methods with short grain milled rice was evaluated. Instant rice produced by process 2 had high rehydration rate, and those by processes 1 and 2 revealed light brown color with less lightness. Instant rice produced by processes 1 and 2 with ammonium carbonate treatment had more uniform porous microstructure, as shown by SEM micrographes, and microstructural difference was noticed between instant rice prepared with government rice and Akibari. Instant rice produced by processes 1 and 2 had less sensory color score, and those by processes 2 and 4 had higher sensory cohesiveness. Overall quality of instant rice produced by process 2 was better, except color.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.4
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• pp.314-324
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• 2016

To improve the color stability of chlorophyll in young barley leaf used as functional green biomaterial, the absorption spectrum, color values, and antioxidative activities of young barley leaf (YBL) treated with zinc ion solutions were investigated. The small pieces of fresh YBL in aqueous solution mixtures were autoclaved twice at $110^{\circ}C$ for 30 min (pH 5). Distilled water (BLA), 0.01% zinc chloride (BLAZ), 0.01% zinc citrate (BLAC), and 0.01% zinc lactate (BLAL) solutions were used. Treated YBL powders were extracted with 80% EtOH for 4 h. Chlorophyll a and b contents differed with different treatments. BLA decreased chlorophyll a and b contents, whereas others were maintained. Absorbance spectrums of chlorophyll at 400~700 nm showed different maximum peak wavelengths. After heating in acidic and neutral solutions (pH 3, 5, and 7), the colors of YBL and BLA changed from green to olive green, whereas BLAZ, BLAC, and BLAL remained green color. The antioxidative activities showed higher values in YBL extract than in treated extracts. From the above results, autoclaved YBL in zinc solution would increase the color stability and maintain green color regardless of acid and heat treatments.

• Korean Journal of Food Science and Technology
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• v.12 no.2
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• pp.82-87
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• 1980

The red color bleaching phenomena of red pepper powder by the exposure to sun light were studied on the various factors such as drying methods of pepper and the storage conditions of pepper powder, relative humidities, particle sizes, and the amounts and qualities of light. The surface color of red pepper was rapidly bleached by the successive daily exposures until the color retention value (capsanthin remained/original capsanthin content) reached to 0.5, while that of dark storge showed a negligible change. The color changes were related with the cumulative solar energy at various water activities $(a_w)$. As decreasing $a_w$ below 0.5, the bleaching reaction was highly accelerated, and thereafter was slowly progressed. Sun lights transmitted by red-, yellow- and blue-gelatin filters, respectivly, bleached in different degrees and at the shorter wavelength light, the more color bleaching occurred. From this fact a red colored package film could be effectivly used for the color preservation purpose in the red pepper storage.

• 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.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.381-385
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• 2011

The degree of maturity of rice greatly affects the quality of the rice, including factors such as the integrity of grains, color, and the nutritive components. Green Rice$^{(R)}$ is rice (Oryza sativa L.) that has been harvested earlier than brown rice and appears green in color. To determine suitable harvesting time of the Jinbu variety of Green Rice$^{(R)}$ in Gyeonggido, rice samples harvested on 23, 26 and 42 days after heading (DAH) were compared on their yield, color intensity, and proximate compositions. The maximum paddy yield of Green Rice$^{(R)}$ was 61.4% at 23 DAH, which decreased to 45.4%, 5.5% at 26 and 42 DAH, respectively. Greenness was darker at 23 DAH ($-0.27{\pm}0.03$), and significantly weaker (p<0.05) at 26 DAH ($0.07{\pm}0.01$) and at 42 DAH ($5.25{\pm}0.08$). All proximate compositions, except carbohydrate, including moisture, crude fat, protein, ash and total minerals were higher in the earlier-harvested Green rice$^{(R)}$ than in brown rice, without variations among the 23 and 26 DAH Green rice$^{(R)}$. Overall, the optimum harvest time of Jinbu Green Rice$^{(R)}$ at Gyeonggido would be 23 DAH. We suggest that timely harvesting could be a potent determinant of the quality of Green Rice$^{(R)}$.

• Food Science of Animal Resources
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• v.44 no.2
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• pp.356-371
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• 2024

Novel meat-inspired products, such as cell-cultivated meat and meat analogues, embrace environmental sustainability, food safety and security, animal welfare, and human health, but consumers are still hesitant to accept these products. The appearance of food is often the most persuasive determinant of purchasing decisions for food. Producing cultivated meat and meat analogues with similar characteristics to conventional meat could lead to increased acceptability, marketability, and profitability. Color is one of the sensorial characteristics that can be improved using color-inducing methods and colorants. Synthetic colorants are cheap and stable, but natural pigments are regarded as safer components for novel food production. The complexity of identifying specific colorants to imitate both raw and cooked meat color lies in the differences in ingredients and methods used to produce meat alternatives. Research devoted to improving the sensorial characteristics of meat analogues has noted various color-inducing methods (e.g., ohmic cooking and pasteurization) and additives (e.g., lactoferrin, laccase, xylose, and pectin). Additionally, considerations toward other meat components, such as fat, can aid in mimicking conventional meat appearance. For instance, the use of plant-based fat replacers and scaffolds can produce a marked sensory enhancement without compromising the sustainability of alternative meats. Moving forward, consumer-relevant sensorial characteristics, such as taste and texture, should be prioritized alongside improving the coloration of meat alternatives.