Colourings lutein

Ingredients Carbonated water. Concentrated fruit juices (pineapple, grapefruit) (5% when reconstituted). Citric acid. Acidity regulator (sodium citrate). Artificial sweeteners (aspartame, saccharin). Flavourings. Preservative (sodium benzoate). Antioxidants (ascorbic acid, ascorbyl palmitate). Colour (lutein)... 

Rodriguez-Carmona, M. et al. (2006). The effects of supplementation with lutein and/or zeaxanthin on human macular pigment density and colour vision. Ophthalmic and Physiological Optics 26 137-147. 

Fig. 2.29. Representative HPLC chromatogram of yellow feathers from an adult male common yel-lowthroat. All-frans-lutein was found in these feathers, plus cis isomers that were formed during the thermochemical extraction process. Chromatograms for the other two yellow-coloured bird species studied here were identical to this one. Reprinted with permission from K. J. McGraw et al. [68],...

Lutein [127-40-2] M 568.9, m 196°, Ej, 1750 (423nm), 2560 (446nm), 2340 (477.5nm) in EtOH X.max in CS2 446, 479 and 511nm. Crystd from MeOH (copper-coloured prisms) or from ethyl ether by adding MeOH. Also purified by chromatography on columns of magnesia or calcium hydroxide, and crystd from CS2/EtOH. May be purified via the dipalmitate ester. Stored in the dark, in an inert atmosphere. 

Oil-soluble egg-yellow colour good stability the xanthophyll lutein is a carotenoid colour which occurs in green leaves, vegetables, eggs and some flowers... 

A variety of C4q carotenes do not yield vitamin A on oxidation and these variously have altered cyclic groups or no cyclic, groups at all and can be variously oxidized or reduced. Good examples are the widespread lutein (X —(IP)2—(PI)2—X ) (yellow) and the non-cyclic carotenes lycopene ( /, /-carotene the orange-red colour of tomatoes and other fruits), -carotene (7,8,7, 8 -tetrahydro- / V"carotenei yellow) and lyc.oxanthin ( /, /-caroten-16-0I yellow). 

Lutein provides a brilliant yellow colouring within a wide range of pH levels. There is also a positive side effect attributed to this natural colour extract from the genus Tagetes lutein is supposed to have positive effects on the long-term health of the human eye. 

With the use of antioxidants it is consequently possible to increase the stability of paprika, carotenes and lutein colours considerably and thereby match... 

Other functions of carotenoids are briefly mentioned here. These include phototropism and phototaxis, reproduction, camouflage colour, precursor role of neoxanthin (38, Fig. 16) for the plant growth hormone abscisic acid and the ant repellent grasshopper ketone [18,41], and cell-cell communication [49], In recent years the function of zeaxanthin (15) and lutein (25) in the human retina has received much attention, cf. the section on Health aspects. 

Lycopene accounts for >85% of the total tomato carotenoids in red-ripe fruits thus causing its characteristic colour (Lenucci et al. 2006 and references therein). This open-chain hydrocarbon with 11 conjugated and two isolated double bonds has the highest degree of unsaturation of all carotenoids. Its concentration varies from 30 to 200mg/kg fresh wt (Topal et al. 2006). Phytoene, p-carotene, and lutein are further quantitatively remarkable constituents (Bums et al. 2003). 

Solanum tuberosum L. Carotenoids, predominantly xanthophylls such as lutein, zeaxanthin, violaxanthin, only traces of carotenes, are present in the flesh of all potato cultivars. However, there are large quantitative differences White-fleshed varieties were determined to contain 50-100 pg/lOOg fresh weight, whereas yellow- to orange-fleshed ones may contain up to 2000 g/100g fresh weight. The colour of red and purple potatoes is caused by anthocyanins (Brown 2005 and references therein). 

Egg yolk and shell colours are important aspects of egg quality in many countries. Egg yolk pigmentation is a complex process influenced by many factors, such as nutrition, carotenoid source, health, egg handling and storage. Egg yolk contains as the main pigments the same xanthophylls and carotenes that occur in the depot fat of hens. The most abundant pigment is lutein/zeaxanthin, followed by p-cryptoxanthin and -carotene and other carotenes occurring in the feed (such as canthaxanthin and P-apo-8 -carotenal). The amount of p-carotene is low (0.3 1% of total carotenoids), as this carotene is quickly metaboKsed. 

Antony, JIX and Shankaranarayana, ML (2001) Lutein. A natural colourant and aphytonutrient for eye health protection. The World of Food Ingredients, April/May, 64—67. 

Figure 7.22 The colour of red, yellow and orange bell peppers is due to the respective accumulation of lutein, zeathanthin and capsanthin. Flavonol and flavone conjugates also occur.

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