Chlorophyll synthetic food colorant

Analysis of Synthetic Chlorophyll-Based Food Colorants.442... 

ANALYSIS OF SYNTHETIC CHLOROPHYLL-BASED FOOD COLORANTS... 

Most stains consist of colored substances of natural origin belonging to the polyphenol, carotenoid, or chlorophyll class. Artificial food colorants, cosmetic ingredients, and decorative dyes complete the stain portfolio. Very often stains are complex mixtures of spilled food preparations or beverages. Combined with oils, fats, or other organic material, such as proteins, starch, or waxes, the properties of stains are quite different from those of isolated dyes. Only a small proportion of all stains is fixed on surfaces by physical adhesion. On fibers, in particular, strong interactions often result in covalent bond formation. This process is more important on cotton than on synthetic fabrics. 

Coloring of food can be accomplished by synthetic or natural dyes. The laws pertaining to food colorings are different from country to country. However, natural products (- dyes, natural) are normally accepted. Examples are cochineal, chlorophyll, carotenes, bixin and betanin as well as - caramel color. 

Various natural pigment classes, such as llavonoids, an-thocyanins, carotenoids, chlorophylls and chlorophyll derivatives, porphyrins, quinones, anthraqinones, be-talains, and so forth are abundant in many famihes of the vegetable and animal kingdoms. As consumers generally dislike the color of synthetic dyes, the concentration and composition of pigments in foods and food products exert a considerable impact on the consumer acceptance and, consequently, on the commercial value of the products. It has been proven many times that one of the main properties employed for the commercial evaluation of the quahty of products is their color that is, an adequate color is an important requirement of marketabihty. 

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. 

The variety of colorants in stains is wide and many are complex, polymeric, and poorly defined. Classes of colorants arising from natural products include porphyrins (e.g., green chlorophyll in grass), carotenoids (e.g., orange carotene and red lycopene), anthocyanins (red, blue, color sensitive to pH), flavones and naphthoquinones (yellow), tannins (brown, e.g., in red wine and tea), humic acids (yellow, tea and coffee), and curcumins (yellow, curry and mustard). In addition, the stain may consist of synthetic molecules such as those used in food and cosmetic products. 

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