Phytochemical and nutritional significance of cactus pear

This review discusses cactus pear fruit with special emphasis on its functi onal components. Besides their nutritional importance, their significance i n plant physiology is also described. Opuntia sp. is characterized by high levels of amino acids, especially proline and taurine. The latter was recen tly re-evaluated in nutritional science as a conditional amino acid and was hitherto virtually unknown in plant tissues. Free amino compounds also tak e part in osmoregulation and play an important role in betaxanthin biosynth esis. In contrast to red beets, cactus pears offer a great palette of colou r hues and therefore may be used as a food colouring free from certificatio n. The mucilages in Opuntia sp. tissue are responsible for water retention and can be used as dietary fibre or food thickening agents. Low in acids, t he fruit is suitable for use in dairy products. With readily absorbable sug ars, high vitamin C and mineral content, as well as containing polyphenols, amino acids and having a pleasant flavour, cactus pear is tailor-made for functional food preparations.