Carotenoids in carrot

Canning at 121°C for 30 min was also responsible for the highest losses of carotenoids in carrot juice, reaching 60% for P- and a-carotene, whereas the lutein level decreased 50%, all accompanied by the formation of 13-c -p-carotene in the largest amount, followed by 13-cA-lutein and 15-cA-a-carotene. Canning (T x = 121°C, F = 5) of sweet com resulted in a decrease of lutein by 26% and zeaxanthin by 29%, accompanied by increased amounts of 13-cis- lutein, 13 -CM-lutein, and 13-c/i-zeaxanthin. ° The relative amounts of cis isomers of lutein, mainly the 13-cis, increased by 15% and of 13-di-zeaxanthin by 20% after com canning." ... 

Baranska M, Baranski R, Schulz H and Nothnagel T. 2006. Tissue-specific accumulation of carotenoids in carrot roots. Planta 224 1028-1037. 

Fig. 4 RP-HPLC separation of the carotenoids in carrots. Peaks 1 = Sudan I, 2 = a-carotene 3 = /3-carotene. (From Ref. 63.)...

Baranska, M., Baranski, R., Schulz, H., and Nothnagel, T. (2006) Tissue-specific accumulation of carotenoids in carrot roots. Planta, 224 (5), 1028-1037. Baranska, M., Baranski, R., Grzebelus, E., and Roman, M. (2011) In situ detection of a single carotenoid crystal in a plant cell using Raman microspectroscopy. Vib. Spectrosc., 56 (2), 166-169. 

Carrot oil—The Hquid or the soHd portion of the mixture, or the mixture itself obtained by the hexane extraction of edible carrots (Daucus carota L.) with subsequent removal of the hexane by vacuum distillation. The resultant mixture of soHd and Hquid extractives consists chiefly of oils, fats, waxes, and carotenoids naturally occurring in carrots. 

The comparison of the light effect on carotenoids in foods is very difficult to carry out because different foods with different isomer compositions are employed at the beginnings of experiments. The presence of large molecules offers some photoprotection to carotenoids in food systems, either by complexation with proteins as found in carrots or acting as a filter to reduce the light incidence. Different storage conditions are often found because different light intensities are used or sometimes they are not even reported and experiments are carried out under air, N2, or in a vacuum. 

Carotenoids from fruits and vegetables can exist as protein-carotenoid complexes (as in the case of green leaf vegetables), crystals (as in carrots or tomatoes), or in oil solution (as in mango and papaya) (West and Castenmiller 1998). Carotenoids commonly found in human blood are lutein, zeaxanthin, (3-cryptoxantliin, lycopene, 13-carotene, and a-carotene. The content of some carotenoids in some fruits and vegetables is shown in Table 7.3. 

Use of cosolvent. Various cosolvents, such as acetone, ethanol, methanol, hexane, dichloromethane, and water, have been used for the removal of carotenoids using SC-CO2 extraction (Ollanketo and others 2001). All these cosolvents except water (only 2% of recovery) increased the carotenoid recovery. The use of vegetable oils such as hazelnut and canola oil as a cosolvent for the recovery of carotenoids from carrots and tomatoes have been reported (Sun and Temelli, 2006 Shi, 2001 Vasapollo and others 2004). For the extraction without cosolvent addition, the lycopene yield was below 10% for 2- to 5-hr extraction time, whereas in the presence of hazelnut oil, the lycopene yield increased to about 20% and 30% in 5 and 8 hr, respectively. The advantages of using vegetable oils as cosolvents are the higher extraction yield the elimination of organic solvent addition, which needs to be removed later and the enrichment of the oil with carotenoids that can be potentially used in a variety of product applications. 

Goto M, Sato M and Hirose T. 1994. Supercritical carbon dioxide extraction of carotenoids from carrots, in Yano T, Matsuno R and Nakamura K, Eds. Developments in Food Engineering, Proc. Sixth International Congress on Engineering and Food, Blackie Academic Professional, London, 835—837. 

M. Baranska, H. Schulz, R. Baranski, T. Nothnagel and L.P. Christensen, In situ simultaneous analysis of polyacetylenes, carotenoids and polysaccharides in carrot roots, J. Agric. Food Chem., 53, 6565-6571 (2005). 

Vitamin Ai (retinol) is derived in mammals by oxidative metabolism of plant-derived dietary carotenoids in the liver, especially -carotene. Green vegetables and rich plant sources such as carrots help to provide us with adequate levels. Oxidative cleavage of the central double bond of -carotene provides two molecules of the aldehyde retinal, which is subsequently reduced to the alcohol retinol. Vitamin Ai is also found in a number of foodstuffs of animal origin, especially eggs and dairy products. Some structurally related compounds, including retinal, are also included in the A group of vitamins. 

Buishand, J. G., and W. H. Gabelman. Investigation on the inheritance of root color and carotenoid content in carrot, Daucus carota. Diss Abstr Int B 1978 39 2656. 

P. Subra, S. Castellani and Y. Garrabos, Supercritical carbon dioxide extraction of carotenoids from carrots, in Proceedings of the 3rd International Symposium on Supercritical Fluids (eds. G. Brunner, M. Perrut), Strasbourg, Tome 2, (1994) 447. 

Many of the colors associated with higher plants (green leaves in the spring and summer, yellow or red leaves in the fall, the orange color of carrots, some colors in flower petals) are due to the presence of pigment molecules such as chlorophylls and carotenoids. In this experiment a mixture of these pigments will be isolated by solvent extraction of plant tissue, separated by chromatography, and the components identified by visible spectrophotometry. 

Retinol and its esters and unesterified tocopherols and tocotrienols possess strong native fluorescence, but neither vitamin D nor vitamin K fluoresce. The carotenoids commonly associated with foods do not fluoresce to any significant extent, except notably phytofluene, which is found in considerable amounts in tomatoes (22) and in smaller amounts in carrots (130) and which fluoresces six times more intensely than retinyl acetate (131). 

CG Edwards, CY Lee. Measurement of provitamin A carotenoids in fresh and canned carrots and green peas. J Food Sci 51 534-535, 1986. 

As /3-carotene also has some vitamin A activity it is sometimes added to products for fortification as well as colourant purposes. If this is the case, the methods outlined above can be used. A more recent reference has used a similar method to look at carotenoid isomers in carrot juices and fortified drinks (Marx et al., 2000). 

One of the highest known concentrations of carotenoids occurs in crude palm oil. It contains about 15 to 300 times more retinol equivalent than carrots, green leafy vegetables, and tomatoes. All of the carotenoids in crude palm oil are destroyed by the normal processing and refining operations. Recently, improved gentler processes have been developed that result in a red palm oil that retains most of the carotenoids. The composition of the carotenes in crude palm oil with a total carotene concentration of 673 mg/kg is shown in Table 6-5. 

Common unit operations of food processing are reported to have only minor effects on the carotenoids (Borenstein and Bunnell 1967). The carotenoid-protein complexes are generally more stable than the free carotenoids. Because carotenoids are highly unsaturated, oxygen and light are major factors in their breakdown. Blanching destroys enzymes that cause carotenoid destruction. Carotenoids in frozen or heat-sterilized foods are quite stable. The stability of carotenoids in dehydrated foods is poor, unless the food is packaged in inert gas. A notable exception is dried apricots, which keep their color well. Dehydrated carrots fade rapidly. 

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