Natural colorants caramels

A systematic study was carried out using in parallel 50 standard solutions for each concentration of three natural colorants (curcumin, carminic acid, and caramel as yellow, red, and brown, respectively). No false positive results for synthetics were obtained up to concentrations of 15 and 20 ng/ml for natural red and yellow colorants, respectively, or 110 ng/ml for natural brown colorant. The concentrations have to be high enough to prove that the screening method is able to accurately discriminate natural and synthetic colorants. To make a clear interpretation of the quantitative UV-Vis spectrum, linear regression analysis was used. Quantitative UV-Vis analysis of a dye ° can be calculated according to the following formula ... 

Orange shades are realized with lipophilic natural colorants like paprika oleo-resin, P-carotene, and canthaxanthin after previous emulsification to yield water-dispersible forms. Yellow shades can be achieved using turmeric as a water-soluble solution, but the solution is light sensitive. To maintain constant color, 3 to 6 ppm of P-carotene may be added. Stable brown coloration is obtained from caramel a concentrated syrup is easily incorporated, well flavored and stable in creams. ... 

Juices extracts (liquorize), spirits (orange, lemon), syrups (black currant), tinctures (ginger), and aromatic waters Mineral pigments (iron oxides), natural colorants, anthocyanins, carotenoids, chlorophylls riboflavine, red beetroot extract, and caramel synthetic organic dyes azo compounds... 

CAS 8028-89-5 EINECS/ELINCS 232-435-9 FEMA 2235 INS150a E150a Synonyms Burnt sugar Burnt sugar coloring Caramel color Natural brown 10 Plain caramel... 

The majority of synthetic food colors are ideal candidates for separation by CE. This is because they commonly contain sulfonic acid or carboxylic acid functional groups that form negatively charged colored ions at alkaline pEI. CE has also been applied to the analysis of natural colors such as caramels, which occur as four distinct classes according to the reactants used during sugar caramelization. CE analysis can be used to identify and quantitate the class of caramel present in a sample. 

Full-bodied mms are akowed to ferment from 12 to 20 days, often relying on natural or wild fermentation in which the mash is inoculated by the yeast present in the air and starting materials. These mms are twice-distiked in pot stiks to 140—160° proof. Full-bodied mms are often aged from five to seven years in oakbarrels. Caramel color can also be added to give them a darker color. They are produced in Jamaica, Barbados, Martinique, Trinidad, and Guyana. 

Exempt colorants are made up of a wide variety of organic and inorganic compounds representing the animal, vegetable, and mineral kingdoms. Some, like -carotene and 2inc oxide, are essentially pure factory-produced chemicals of definite and known composition. Others, including annatto extract, cochineal extract, caramel, and beet powder are mixtures obtained from natural sources and have somewhat indefinite compositions. 

This difference in kinetics was exploited to develop a procedure to determine free and reversibly bound sulfite in food. The mobile phase consisted of an aqueous solution of 0.05 M tetra-butylammonium hydroxide adjusted to the desired pH by the addition of glacial acetic acid (34). Fluorimetric detection is also possible, because a reaction of the formaldehyde-bisulfite complex with 5-aminofluorescein gives a nonfluorescent product. The sulfite is measured indirectly by its suppresion of the fluorescence of the reagent (31). This method is applicable to the determination of S02 at > 10 ppm and is not applicable to dark-colored foods or ingredients where SO, is strongly bound, e.g., caramel color. This method does not detect naturally occurring sulfite. Sulfur dioxide is released by direct alkali extraction. 

Many Italian producers use refined beet sugar for sweetening, whereas in France mistelas (fortified grape must) is preferred. Caramel is an important constituent where color intensification is desired and is prepared carefully for that purpose (Goswell and Kunkee, 1977). In American vermouth, wine of higher natural acidity is used. 

Caramel colors are brown pigments produced by reaction of a saccharide with a browning accelerator. They can be considered a natural material as caramels may be formed in food. Caramels are prepared as food colors by heating a solution of a sugar (commonly glucose or sucrose) with the accelerator. The caramels can be classified as one of four types [1] shown in Table 11.1.1. 

Aldoses undergo the Amadori rearrangement and subsequently turn into caramels, the natural brown food colorants, and/or heteroaromatic compounds — derivatives of pyrrole, imidazole, and pyrazine. Ketoses react similarly into ketosylamino acids or ketosylamines, which, in the first step, undergo the Heyns rearrangement (5.17-5.23). These rearrangements are the first steps of either thermal or enzymatic (the Maillard reaction) reactions resulting in the browning of food and the aroma of roasted, baked, or fried foodstuffs. 

By taking advantage of the Stille reaetion, 90, a naturally oeeurring imidazole alkaloid was synthesized [55-58]. Pyne and Cliff proteeted 4-iodoimidazole with ehloromethylethyl ether, forming two tautomers 86 and 87 in a 1 9 ratio. After isolation, the Stille eoupling of 87 with vinylstannane 88 [( ) (Z) = 88 22] afforded isomerically pure alkene 89, whieh was then manipulated in five additional steps into (17 , 25, 37 )-2-acetyl-4(5)-(l,2,3,4-tetrahydroxybutyl)imidazole (THI, 90), a constituent of Caramel Color III. 

The classification of food colorants on a chemical basis is also not always clear. Although Proudlove (1994) and DeMann (1980) agree on three chemical classes for natural food colorants that is, isoprenoid derivatives, tetrapyrrole derivatives and benzopyran derivatives, DeMann (1980) also includes a fourth group called artefacts to include the melanoidins and caramels. Table 7.1 shows the classification based on chemical stmcture, the fourth group artefacts has been included as this is relevant to the discussion of chemical stmcture and light absorption. Table 7.1 also includes the names used by Dalzell (1997) in her classification. 

Apart from the derivatives of p-carotene, other pigments are the anthocyanins, the chlorophylls, cochineal, the betalaines, turmeric, caramel and riboflavin. In this account the historical background in brief, the chemistry of these pigments, their extraction from natural sources and their synthesis will be discussed. The present permitted natural substances and nature-identical synthetic materials (also described by the Food and Drugs Administration, the FDA, as colorants exempt from certification ) is quite small in number. Reference is also made to colourants no longer listed but which have an historical organic chemical significance such as for example brazilin and its relative haematoxylin. 

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