Search results for "Provitamin a"
showing 2 items of 2 documents
Carotenoids and Color of Fruit Juice and Milk Beverage Mixtures
2007
Seventeen commercially available, "ready to drink" fortified beverages consisting of mixtures of fruit juices and milk were analyzed to evaluate their carotenoid profile (including their Z/E stereoisomers) and color during their commercial shelf life. Lightness (L*) was found to be correlated with the content of milk in the mixtures (r= 0.649) whereas red-yellow colors were correlated with the contents of alpha-carotene, beta-cryptoxanthin, and beta-carotene supplied by the fruit. The beverages stored under refrigeration (4 +/- 2 degrees C) showed higher luminosity (L*) and higher saturation of color (C*) and yellowness (b*). Differences (P < 0.05) in the levels of carotenoids were found am…
Food carotenoids and cancer prevention: an overview of current research
1997
Carotenoids are plant pigments that are present in the human diet as microcomponents of fruit and vegetables. Since 1980, a consistent bulk of the results from both epidemiologic and experimental studies has strongly suggested that β-carotene, a widespread food carotenoid with provitamin A activity, could prevent the onset of cancers, especially lung cancer. Unfortunately, subsequent large-scale intervention studies failed, with one exception, to demonstrate any chemopreventive potency for β-carotene supplementation in humans, revealing a lack of knowledge of the mechanisms involved. In addition to their antioxidant properties, which have long been thought to be the clue to their biological…