Stable Red Pigments Research Articles

Investigation of the Changes in Rheological Properties of Purple Basil Sherbet Samples Concentrated by Ohmic Heating at Different Voltage Gradient

Purple basil is widely used medicinally and aromatically due to its essential oil properties, and it is a plant that stands out with its antibacterial, antimutagenic and antioxidant properties. It has been determined that purple basil has positive effects on health such as appetizing, insomnia, sputum, diuretical and antispasmodic. Purple basil contains high concentrations of anthocyanins and with these properties it stands out as a potential new source of stable red pigments for the food industry. In recent years, it has been seen that purple basil has been processed into different products such as tea and sherbet in order to benefit from its functional properties. With the processing of purple basil into different products, it is seen that the consumption of basil and basil products has increased by consumers. In this study, purple basil sherbet samples were concentrated at different voltage gradient values (14, 17 and 20 V/cm) under atmospheric conditions with ohmic heating up to 25% soluble solid content (SSC) and the changes in their rheological properties during the concentration process was investigated. The changes in the rheological properties of the purple basil samples were determined in the range of 1-148 s-1 shear rate values and measurement temperature was 25°C. The compatibility of different rheological models (Newton, Power-Law and Herschel-Bulkley) to the experimental data was statistically evaluated to determine the flow behavior index of the purple basil sherbet samples. It has been determined that the shear stress values increased as the shear rate values increased in all the process conditions. Similarly, at the same shear rate values, it was determined that the shear stress values increased as the SSC values increased. It has been determined that the best suitable rheological model was Herschel-Bulkley Model for all purple basil sherbet concentrates. It is thought that the results obtained will provide important data to the food and machinery industry for the installation of pilot and industrial scale ohmic heating systems.

ХИМИЧЕСКОЕ ИЗУЧЕНИЕ СОСТАВА АНТОЦИАНОВ ТРАВЫ OCIMUM BASILICUM L.

Abstract. Sweet basil − Ocimum basilicum L. contains a wide spectrum of biologically active compounds: essential oils, phenolic compounds, including flavonoids and anthocyanins. The violet variety is a rich source of acylated and glycosylated anthocyanins and can be of interest as a unique source of stable red pigments for the food industry. The HPLC method has determined the chemical composition of O. basilicum L.anthocyanins: it contains 12 anthocyanin glycosides, and these compounds are in the form of depsides with hydroxy-cinnamic acids, as evidenced by their characteristic UV profiles. The aglycone of anthocyanin glycosides is cyanidin, which was confirmed by the acid hydrolysis. And 11 anthocyanin glycosides are represented as depsides with p-coumaric acid. One anthocyan glycoside is in the form of a depside with caffeic acid. The quantification of anthocyanins was determined by the pH-differential spectrophotometry. It was found that the fresh O. basilicum L. raw material total content of anthocyanins was – 0,48 ± 0,054%.

J. Cosmet. Sci., 59, 431–440 (September/October 2008) Red pigment from Lithospermum erythrorhizon by supercritical CO2 extraction

SynopsisIn this study, a stable red pigment was prepared from Lithospermum erythrorhizon via supercritical carbon dioxide extraction. The optimal extraction conditions were 400 bar and 60°C. The patch tests indicated that up to 10% of the red pigment was acceptable from a skin irritation standpoint. According to the results of the CIE LAB chromaticity test, the color difference was acceptable when compared to commercial synthetic red pigments. The light‐illuminated color stability test indicated that the pigment was more stable than the red pigment extracted with ethanol. The higher stability was also demonstrated in the DPPH anti‐oxidant activity test. The supercritical red pigment harbored elevated amounts of shikonin and derivatives, and appears to be usable as a stable red pigment for cosmetic color products.

Stabilization of anthocyanins on thermally processed red D'Anjou pears through complexation and polymerization

Stabilization of red anthocyanins on the surface of thermally processed red pears (D'Anjou) through complexation with metallic ions and polymerization was investigated. Pears were treated briefly in an aqueous solution containing stannous (Sn) ion, hydrochloric acid, formaldehyde, and tannic acid prior to steaming and canning processes. Polymerization capacity of the treatment solutions was investigated by monitoring the haze formation of the solutions. Aqueous acetone extracts of the peels from fresh and treated pears at major processing steps (pre-treatment, steam-heating, and canning) were subjected to HPLC qualitative analysis on anthocyanins. The total phenolics (TP) and anthocyanin content (ACN) of the peels were measured by Folin–Ciocalteu assay and pH-differential method, respectively. Polymerization capacity of the solution was influenced by the composition, setting-time, and the time of Sn addition into the formulated solutions. The pre-treatment along with steam-heating resulted in stable red pigments on the peels of canned pears. The new pigments are believed to be the complexes of stannous and phenolics, including anthocyanins. No major newly formed anthocyanins or small phenolics were detected in treated pears. Although developed treatment formula did not represent a commercial application yet, this study revealed an effective approach of retaining red anthocyanins on thermally processed fruits.

Effect of SiO2 and Al2O3 on the synthesis of Fe2O3 red pigment

Fe2O3 red pigments, especially hematite particles have been widely utilized in many technologies, such as pigments, catalysts, coatings, flocculants, cosmetics, electronic materials ad abrasives. There are many commercially available Fe2O3 powders for use as red pigment for Japanese porcelain enamel. However, the tone of red color of Fe2O3 pigments was strongly influenced by synthesized temperature. It was important that the color-stable pigments, which were not affected by morphology and dispersal behavior, were synthesized for use as thermally stable red pigments. The present work was to study the possibility of synthesizing red inorganic pigments by composite of Fe2O3, Al2O3 and SiO2.

Extraction properties and absorption spectra of dry cured hams made with and without nitrate

The spectral and extraction properties of nitrate-free dried hams (Parma hams) were studied as a function of maturing time and muscle type ( semimembranosus and biceps femoris muscles). To understand the red colour of the processed meat, a three-step extraction using water, acetone and tetrahydrofuran (THF) as solvents was employed and the extracts from each step were submitted to spectrophotometric (visible) analysis while the corresponding residues underwent instrumental (CIE L* a* b*) colour evaluation. Results showed that the drier the meat the more the pigment is soluble in organic solvents, THF proving a major extractant in matured hams, regardless of muscle type. When Parma hams were compared with hams made using nitrate, the former displayed more intense ( P<0.05) absorption in the red region in the aqueous solution, lower intensities in acetone and higher values in THF solution. Major differences in spectral characteristics were found between water and organic extracts of Parma hams, with both acetone and THF solutions exhibiting a doublet at 544–584 nm, and water extracts displaying two distorted peaks at 551 and 595 nm. It is concluded that dry curing of meat without nitrate yields a lipophylic stable red pigment whose hydrophobicity increases with ageing.

Anthocyanins in Basil (Ocimum basilicum L.)

The Lamiaceae family, which includes basil, sage, and thyme, has long been recognized as a rich source of diverse and unique anthocyanins. The development of intensely purple pigmented basil in the ornamental and herb trade prompted this examination of eight commercial varieties of purple basils (Ocimum basilicum L.) as a potential new source of anthocyanins. Anthocyanins were isolated and characterized utilizing high-performance liquid chromatography, spectral data, and plasma desorption mass spectrometry. Fourteen different anthocyanins were isolated, consisting of 11 cyanidin-based pigments and 3 peonidin-based pigments. The large-leaf basil varieties, Purple Ruffles, Rubin, and Dark Opal, had an average extractable total anthocyanin content ranging from 16.63 to 18.78 mg/100 g of fresh tissue, while the ornamental small-leaf variety, Purple Bush, had only 6.49 mg/100 g of fresh tissue. The highest concentration of total anthocyanins occurred just prior to flowering, although by day 8 seedlings already had accumulated all 14 anthocyanins. Comparisons were made to other anthocyanin sources, with results showing that purple basils are an abundant source of acylated and glycosylated anthocyanins and could provide a unique source of stable red pigments to the food industry. Keywords: Basil; Ocimum basilicum L.; anthocyanins; HPLC; plasma desorption mass spectrometry

A new class of wine pigments generated by reaction between pyruvic acid and grape anthocyanins

A new class of stable red pigments detected in grape pomace was analysed by electrospray ionisation mass spectrometry. They were shown to be pyruvic acid derivatives of genuine grape anthocyanins by synthesis experiments. The major product was identified by NMR ( 1H, NOE, HSQC, HMBC) experiments as the malvidin-3-monoglucoside pyruvic acid adduct. Its formation results from cyclisation between C-4 and the hydroxyl group at C-5 of the original flavylium moiety with the double bond of the enolic form of pyruvic acid, followed by dehydration and rearomatisation steps. This type of reaction leads to increased colour stability. Various yeast metabolites other than pyruvic acid were shown to react with grape anthocyanins following this mechanism, suggesting that it may be an important route of conversion into stable pigments during the maturation and ageing of wine.

Polyphenols produced during red wine ageing.

Over the past few years, it has been accepted that a moderate red wine consumption is a factor beneficial to human health. Indeed, people of France and Italy, the two major wine-producing European countries, eat a lot of fatty foods but suffer less from fatal heart strokes than people in North-America or in the northern regions of Europe, where wine is not consumed on a regular basis. For a time, ethanol was thought to be the "good" chemical species hiding behind what is known as the "French paradox". Researchers now have turned their investigations towards a family of natural substances called "polyphenols", which are only found in plants and are abundant in grapes. It is well known that these molecules behave as radical scavengers and antioxidants, and it has been demonstrated that they can protect cholesterol in the LDL species from oxidation, a process thought to be at the origin of many fatal heart attacks. However, taken one by one, it remains difficult to demonstrate which are the best polyphenols as far as their antioxidant activities are concerned. The main obstacle in that kind of research is not the design of the chemical and biological tests themselves, but surprisingly enough, the limited access to chemically pure and structurally elucidated polyphenolic compounds. In this article, particular attention will be paid to polyphenols of red wine made from Vitis vinifera cultivars. With respect to the "French paradox", we address the following question: are wine polyphenolic compounds identical to those found in grapes (skin, pulp and seed), or are there biochemical modifications specifically taking place on the native flavonoids when a wine ages? Indeed, structural changes occur during wine conservation, and one of the most studied of those changes concerns red wine colour evolution, called "wine ageing". As a wine ages, it has been demonstrated that the initially present grape pigments slowly turn into new more stable red pigments. That phenomenon goes on for weeks, months and years. Since grape and wine polyphenols are chemically distinct, their antioxidant activities cannot be the same. So, eating grapes might well lead to beneficial effects on human health, due to the variety and sometimes large amounts of their polyphenolic content. However, epidemiological surveys have focused on wines, not on grapes....

ChemInform Abstract: Stabilization of Tetravalent Praseodymium in CeO2. Application as Stable Red Pigments at High Temperature.

AbstractThe new red pigments (III) have been prepared by different methods, one of them is shown in the scheme.

イミダゾールおよびアミノ酸誘導体によるたらこの発色法

The pink color of the salted Alaska Pollack roe, “Tarako”, which is cured with either nicotinamide and ascorbate or nicotinic acid and ascorbate is stable under roe product is markedly unstable and fades rapidly accompanying development of a dark hue during storage in a refrigerator.The color fixation of the salted Alaska pollack roe with imidazole was studies, based on zhe finding that imidazole is capable of forming a fairly stable red pigment, a ferrihemochrome, with hematin and denatured myoglobin. The fresh roe, when salted with 12% NaCl, 0.5% imidazole, and 0.3% ascorbate, rapidly developed the stable red color which was presumed, to be due to the formation of imidazole ferrihemochrome. The fixed color was red with some orange tints, slightly differing from the pink color developed by means of means of nitrite. Similar results were obtained with histidine menthyl ester and histidylhistidine both of which are capable of forming ferrihemochromes.