|MadSci Network: Botany|
Plant pigments in fruits and vegetables are mainly chlorophylls (greens), anthocyanins (blues, purples, reds) and carotenoids (reds, yellows, oranges). In ten plant families that lack anthocyanins, the major fruit and flower pigments are betalains. The most familiar of these is betanin from red beet roots. The orange in carrots is due to the carotenoid, carotene. The red in tomato is due to the carotenoid, lycopene. The red in red cabbage is due to anthocyanins that are pH sensitive. They are red in acid solution, purple in neutral, and blue in basic. A pH indicator can be made from a variety of anthocyanin containing fruits and vegetables, such as blueberries, cherries, blackberries, red onions, grapes, and radishs. References MadSci Anthocyanins FAQ Red Cabbage pH Indicator Cabbage Juice Indicator Salisbury, F.B. and Ross, C.W.. 1985. Plant Physiology. Belmont, CA: Wadsworth.
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