Raspberries are an important commercial fruit crop, widely grown in all temperate regions of the world. Many of the most important modern commercial red raspberry cultivars derive from hybrids between R. idaeus and R. strigosus. Some botanists consider the Eurasian and American red raspberries to all belong to a single, circumboreal species, Rubus idaeus, with the European plants then classified as either R. idaeus subsp. idaeus or R. idaeus var. idaeus, and the native North American red raspberries classified as either R. idaeus subsp. strigosus, or R. idaeus var. strigosus.
The black raspberry, Rubus occidentalis, is also occasionally cultivated in the United States, providing both fresh and frozen fruit as well as jams, preserves, and other products, all with that species' distinctive, richer flavor.
Purple-fruited raspberries have been produced by horticultural hybridization of red and black raspberries, and have also been found in the wild in a few places (for example, in Vermont) where the American red and the black raspberries both grow naturally. The unofficial name Rubus × neglectus has been applied to these native American plants for which commercial production is rare.
Red and black raspberry species have albino-like pale-yellow variants resulting from expression of recessive genes for anthocyanin pigments. Variously called golden raspberries, yellow or (rarely) orange raspberries retain the distinctive flavor of their respective species. In the eastern United States, most commercially sold pale-fruited raspberries are derivatives of red raspberries. Yellow-fruited variants of the black raspberry occur occasionally in the wild or are grown in home gardens.
Nutrients and potential health benefits
Raspberries rank near the top of all fruits for antioxidant strength, particularly due to their dense contents of ellagic acid (from ellagotannins), quercetin, gallic acid, anthocyanins, cyanidins, pelargonidins, catechins, kaempferol and salicylic acid. Yellow raspberries and others with pale-colored fruits are lower in anthocyanins.
Due to their rich contents of antioxidant vitamin C and the polyphenols mentioned above, raspberries have an ORAC value (oxygen radical absorbance capacity) of about 4900 per 100 grams, including them among the top-ranked ORAC fruits. Cranberries and wild blueberries have around 9000 ORAC units and apples average 2800.
The following anti-disease properties have been isolated in experimental models. Although there are no clinical studies to date proving these effects in humans, preliminary medical research shows likely benefit of regularly consuming raspberries against:
- inflammation
- pain
- cancer
- cardiovascular disease
- diabetes
- allergies
- age-related cognitive decline
- degeneration of eyesight with aging
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