Colorants lycopene

Lycopene (T, T -carotene) is a red, acyclic carotenoid found in high concentrations in the tomato (Fig. 1), its high microcrystalline deposition in chromoplasts of the peel and flesh being responsible for their characteristic red color. Lycopene contributes about 80% to the total carotenoid content of tomatoes the remainder includes carotenoid precursors. 

Many organic compounds such as lycopene are colored because their HOMO-LUMO energy gap is small enough that appears m the visible range of the spec trum All that is required for a compound to be colored however is that it possess some absorption m the visible range It often happens that a compound will have its k m the UV region but that the peak is broad and extends into the visible Absorption of the blue to violet components of visible light occurs and the compound appears yellow... 

Carotenoids are natural pigments characterized by a tail to tail linkage between two C20 units and an extended conjugated system of double bonds They are the most widely dis tributed of the substances that give color to our world and occur m flowers fruits plants insects and animals It has been estimated that biosynthesis from acetate produces approximately a hundred million tons of carotenoids per year The most familiar carotenoids are lycopene and (3 carotene pigments found m numerous plants and easily isolable from npe tomatoes and carrots respectively... 

Another colorful carotene is lycopene. This is the red molecule that gives ripe tomatoes their color. 

Carotenoids are also present in animal products such as eggs, lobsters, greyflsh, and various types of hsh. In higher plants, they occur in photosynthetic tissues and choloroplasts where their color is masked by that of the more predominant green chlorophyll. The best known are P-carotene and lycopene but others are also used as food colorants a-carotene, y-carotene, bixin, norbixin, capsanthin, lycopene, and P-apo-8 -carotenal, the ethyl ester of P-apo-8-carotenic acid. These are Upid-soluble compounds, but the chemical industry manufactures water-dispersible preparations by formulating coUoid suspensions by emulsifying the carotenoids or by dispersing them in appropriate colloids. ... 

Most of this amount is in the form of fucoxanthin in various algae and in the three main carotenoids of green leaves lutein, violaxanthin, and neoxanthin. Others produced in much smaller amounts but found widely are p-carotene and zeaxanthin. The other pigments found in certain plants are lycopene and capsanthin (Figure 2.2.1). Colorant preparations have been made from all of these compounds and obviously the composition of a colorant extract reflects the profile of the starting material. Carotenoids are probably the best known of the food colorants derived from natural sources. ... 

Lycopene is a bright red pigment that colors several ripe fruits, vegetables, and flowers. Tomato and tomato products are the main dietary sources of this carotenoid, although it is also found in watermelons, guavas, pink grapefruits, and in small quantities in at least 40 plants. - The absorption of lycopene in the human gut is increased by heat treatment, probably because the breakdown of the plant cells makes the pigment more accessible. ... 

Fruifs and vegetables also contain ofher bioactive substances such as polyphenols (including well-known pigments anthocyanins, flavonols) and non-provitamin A carotenoids (mainly lycopene, lutein, and zeaxanthin) that may have protective effects on chronic diseases. Polyphenols and carotenoids are known to display antioxidant activities, counteracting oxidative alterations in cells. Besides these antioxidant properties, these colored bioactive substances may exert other actions on cell signaling and gene expression. 

Lycopene is well known as the predominant carotene in tomatoes, accounting for 65 to 98% of the total colored carotenoid content, depending on the cultivar (Table 4.2.3). The levels of lycopene in fresh tomatoes for salad varied from 21 to 79 g/g 34,35 jjj tomatoes for processing and deep-red tomatoes, the level of lycopene can be as high as 623 More than 80% of the tomatoes produced are... 

Among tropical fruits, red guavas, containing 76 to 86% of lycopene in relation to total carotenoid, can be considered good sources of lycopene. An indigenous Southeast Asia fruit called gac in Vietnam and used as a rice colorant shows an intense red color in the seed membrane (seed pulp or aril) of the ripe fruit the mesocarp, characterized by its yellow color, is discarded. Although some discrepancies can be found in the literature regarding the lycopene content in gac fruits (Table 4.2.3), this fruit is an extraordinarily rich source of lycopene. ... 

Consumer acceptance of fresh and processed fruits and vegetables is influenced by product appearance, flavor, aroma, and textural properties. Color is a key component that influences a consumer s initial perception of fruit and vegetable quality. Lycopene is the principal carotene in tomato fruit that imparts color. Analytical and sensory... 

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