Carotenoids stability

CO2 density on extraction of all-ira 5-lycopene from tomatoes and found the greatest yield at the highest density (0.90 g/mL) tested. However, while SFE is a relatively mild extraction technique, it is still necessary to consider the effect of extraction conditions on carotenoid stability to minimize the formation of isomer artifacts (Spanos et ah, 1993). 

LUKTON, A. and mackinney, g. (1956). Effect of ionising radiations in carotenoid stability. Food Technol. 10, 630-632. 

Fig. 15.57. Carotenoid stability in pasta products made of three Durum wheat cultivars as affected by added ascorbic acid (according to Walsh et al., 1970). 1-3 wheat cv. Durum...

The carotenoid concentration of paprika also depends on the variety of pepper used. Fresh ripe fruits, dried fruits, and ground paprika from the Agridulce pepper variety consistently have a higher carotenoid content than those from the Bola variety (Minguez-Mosquera and Homero-Mendez, 1994). Variations in the carotenoid stabilities of different industrially processed paprika samples are mainly due to intrinsic differences between the pepper varieties used, rather than to processing factors. 

PENG Y s, PENG Y M, MCGEE D L and ALBERTS D s (1994) Carotenoids, tocopherols and retinoids in human buccal mucosal cells intra- and inter-individual variability and storage stability. J Clin Nutr 59(3) 636-43. 

MORTENSEN A, SKIBSTED L H (1997) Relative stability of carotenoid radical cations and homologue tocopheroxyl radicals. A real time kinetic study of antioxidant hierarchy. FFBS Letters, 417, 261-6. 

In the carotenoid radicals, the unpaired electron is highly delocalized over the conjugated polyene chromophore. This has a stabilizing effect and also allows subsequent reactions. The cation and anion radicals can be detected by their characteristic spectral properties, with intense absorption in the near-infrared region. 

Delgado-Vargas, R, Jimenez, A.R., and Paredes-Lopez O., Natural pigments carotenoids, anthocyanins, and betalains — characteristics, biosynthesis, processing, and stability, Crit. Rev. Food Sci. Nutr., 40, 173, 2000. 

Antioxidant and Prooxidant Actions and Stabilities of Carotenoids In Vitro and In Vivo and Carotenoid Oxidation Products... 

Many reviews have been written about the antioxidant activities of carotenoids. Some also describe prooxidant activities. - In consequence, only selected points about this very broad subject will be presented in the first part of this chapter. Linked to these properties and important for food nutritional value is the stability of caro-... 

Stndies of the antoxidation of carotenoids in liposomal suspensions have also been performed since liposomes can mimic the environment of carotenoids in vivo. Kim et al. stndied the antoxidation of lycopene," P-carotene," and phytofluene" " in liposomal snspensions and identified oxidative cleavage compounds. Stabilities to oxidation at room temperature of various carotenoids incorporated in pig liver microsomes have also been studied." The model took into account membrane dynamics. After 3 hr of reactions, P-carotene and lycopene had completely degraded, whereas xanthophylls tested were shown to be more stable. 

Carotenoid oxidation products, as carotenoids, may exert protective or detrimental effects on human health. Efforts must be made to try to identify them in vivo where they may appear in lower quantities than carotenoids. Studies of abiotic systems can provide great support for their identification and the comprehension of their stability and reactivity. 

Socaciu, C., Jessel, R., and Diehl, H.A., Carotenoid incorporation into microsomes yields, stability and membrane dynamics, Spectrochim. Acta A Mol. Biomol. Sped, 56, 2799, 2000. 

Carotenoids in Foods Sources and Stability during Processing and Storage... 

The effects of temperature on carotenoid content can be considered from three perspectives (1) evaluation of stability or retention of carotenoids, (2) study of the chemical changes (isomerization, oxidation, epoxy-furanoid rearrangement), and (3) their effects on the nutritional value and other carotenoid actions in humans. The first two topics are discussed in the following sections. The third is presented in Section 3.2.4.1 of Section 3.2. 

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