Pigments in Vegetables

Vegetables contain several classes of pigments: the green chlorophylls; the yellow, orange, and red carotenoids; the red, blue, or violet anthocyanins; andthered-violet betalains. Thisbookcoversthechlorophyllsandthecarot- enoids, the two chief classes of vegetable pigments, and is the first major compilationofthis kind. Structure, physical and chemical properties, and analytical methods, in- cluding special methods adapted for certain vegetables, are discussed first, and are then followed by a discussion of physiological and biochemical as- pects, including location, biosynthesis, and biochemical changes during plant developmentand senescence. Both pigment classes have extremelyimportant biological functions. The chlorophylls are of paramount importance in photosynthesis. The carot- enoids, besides their photofunction, have a highly significant role in nutri- tion. Someofthem havevitaminA value and, possibly, a rolein the preven- tion of human cancer. The chlorophyll distribution table includes all ofthe currentlyavailable quantitativedataonvegetables.
The discussion of carotenoid distribution describes the unique carot- enoids found invegetablesandincludesqualitativeandquantitativedistribu- tion tables for the most common vegetables. These tables summarize all of the publisheddata to date, but they are far from complete. However, appli- cationofrecentlyavailabletechniques should fill theenormousgaps, update old data, and permit an accurate assessment of the vitamin A value of the food. Suchcompletedatawould also make it possible to usecarotenoid dis- tributioninthetaxonomyofvegetables. The presentations of pigment distribution also consider the changes in pigmentcontentduring storageand processing. Thebookalsoincludesapresentationoffactors affectingpigmentsynthe- sis in vegetables (e.g., phytohormones) and environmental factors (e.g., light, temperature), as well as fertilizers and pesticides.