The blackberry is an edible fruit produced by any of several species in the Rubus genus of the Rosaceae family. The fruit is not a true berry; botanically it is termed an aggregate fruit. The plants typically have biennial canes and perennial roots. Blackberries and raspberries are also called caneberries or brambles. It is a widespread, and well known group of over 375 species, many of which are closely related apomictic microspecies native throughout the temperate northern hemisphere and South America.
Blackberries are perennial plants which typically bear biennial stems ("canes") from the perennial root system. Unmanaged mature plants form a tangle of dense arching stems, the branches rooting from the node tip on many species when they reach the ground. Vigorous and growing rapidly in woods, scrub, hillsides and hedgerows, blackberry shrubs tolerate poor soils, readily colonizing wasteland, ditches and vacant lots. The flowers are produced in late spring and early summer on short racemes on the tips of the flowering laterals. Each flower is about 2-3 cm in diameter with five white or pale pink petals. The newly developed primocane fruiting produces flowers and fruits on the new growth.
The drupelets only develop around ovules that are fertilized by the male gamete from a pollen grain. The most likely cause of undeveloped ovules is inadequate pollinator visits. Even a small change in conditions, such as a rainy day or a day too hot for bees to work after early morning, can reduce the number of bee visits to the flower, thus reducing the quality of the fruit. However, the early flowers typically form more drupelets than the later ones because the early flower buds develop over a longer period during the dormant period. Incomplete drupelet development can also be a symptom of exhausted reserves in the plant's roots, or infection with a virus such as Raspberry bushy dwarf virus.
In botanical terminology, the fruit is not a berry, but an aggregate fruit of numerous drupelets ripening to black or dark purple. Blackberry leaves are food for certain caterpillars; some grazing mammals, especially deer, are also very fond of the leaves. Caterpillars of the concealer moth Alabonia geoffrella have been found feeding inside dead blackberry shoots.
Primary cultivation takes place in the state of Oregon located in the United States of America. Recorded in 1995 and 2006: 6,180 acres (25.0 km2) to 6,900 acres (28 km2) of blackberries, producing 42.6 to 41.5 million pounds, making Oregon the leading blackberry producer in the world. While Oregon may lead the world in volume of fruit produced, Serbia has tremendous acreage and Mexico has had dramatically increasing acreage and may soon lead the world.
The soft fruit is popular for use in desserts, jams, seedless jellies and sometimes wine. Since the many species form hybrids easily, there are numerous cultivars with more than one species in their ancestry. Good nectar producers, blackberry shrubs bearing flowers yield a medium to dark, fruity honey.
The blackberry is known to contain polyphenol antioxidants, naturally occurring chemicals that can upregulate certain beneficial metabolic processes in mammals. The astringent blackberry root is sometimes used in herbal medicine as a treatment for diarrhea and dysentery. The related but smaller dewberry can be distinguished by the white, waxy coating on the fruits, which also usually have fewer drupelets. (Rubus caesius) is in its own section (Caesii) within the subgenus Rubus.
In some parts of the world, such as in Australia, Chile, New Zealand and the Pacific Northwest region of North America, some blackberry species, particularly Rubus armeniacus (syn. R. procerus, 'Himalaya') and Rubus laciniatus ('Evergreen') are naturalised and considered an invasive species and a serious weed. As there is forensic evidence from the Iron Age Haraldskaer Woman that she consumed blackberries some 2500 years ago, it is reasonable to conclude that blackberries have been eaten by humans over thousands of years.
Nutrients and antioxidant qualities
Blackberries are notable for their high nutritional contents of dietary fiber, vitamin C, vitamin K, folic acid – a, B vitamin, and the essential mineral, manganese.
Nutrients in raw Blackberries: Value per 100 g (% Daily Value)
Energy 43 kcal | Dietary fiber 5.3 g (21%) |Sugars 4.9 g
Calcium29 mg (3%) | Magnesium20 mg (5%)
Manganese 0.6 mg (32%) | Copper0.2 mg (8%)
Potassium 162 mg (5%) | Sodium1 mg (0%)
Vitamin C, total ascorbic acid21 mg (35%)
Vitamin A214 IU (4%) | Vitamin K20 μg (25%)
Folic acid36 μg (9%) | Carotene, beta128 μg
Lutein + zeaxanthin118 μg
Source: USDA Nutrient database
Blackberries rank highly among fruits for antioxidant strength, particularly due to their dense contents of polyphenolic compounds, such as ellagic acid, tannins, ellagitannins, quercetin, gallic acid, anthocyanins andcyanidins.
Blackberries have an ORAC value (oxygen radical absorbance capacity) of 5347 per 100 grams, including them among the top-ranked ORAC fruits. Another report using a different assay for assessing antioxidant strength placed blackberry at the top of more than 1000 antioxidant foods consumed in the United States.
Nutrient content of seeds
Blackberries are exceptional among other Rubus berries for their numerous, large seeds not always preferred by consumers. They contain rich amounts of omega-3 (alpha-linolenic acid) and -6 fats (linoleic acid), protein, dietary fiber, carotenoids, ellagitannins and ellagic acid.