During World War II, most fruits rich in vitamin C, such as oranges, became almost impossible to obtain in the United Kingdom. Since blackcurrant berries are a rich source of vitamin C and blackcurrant plants are suitable for growing in the UK climate, blackcurrant cultivation was encouraged by the British government. Soon, the yield of the nation's crop increased significantly. From 1942 on, almost the entire British blackcurrant crop was made into blackcurrant syrup (or cordial) and distributed to the nation's children free, giving rise to the lasting popularity of blackcurrant flavourings in Britain.
Blackcurrants were once popular in the United States as well, but became rare in the 20th century after currant farming was banned in the early 1900s, when blackcurrants, as a vector of white pine blister rust, were considered a threat to the U.S. logging industry.The federal ban on growing currants was shifted to jurisdiction of individual states in 1966, and was lifted in New York State in 2003 through the efforts of horticulturist Greg Quinn. As a result, currant growing is making a comeback in New York, Vermont, Connecticut and Oregon. However, several statewide bans still exist including Maine and New Hampshire.
Nutrients and phytochemicals
The fruit has extraordinarily high vitamin C content (302% of the Daily Value per 100 g, table), good levels of potassium, phosphorus, iron and vitamin B5, and a broad range of other essential nutrients (nutrient table, right).
Other phytochemicals in the fruit (polyphenols/anthocyanins) have been demonstrated in laboratory experiments with potential to inhibit inflammation mechanisms suspected to be at the origin of heart disease, cancer, microbial infections or neurological disorders like Alzheimer's disease. Major anthocyanins in blackcurrant pomace are delphinidin-3-O-glucoside, delphinidin-3-O-rutinoside, cyanidin-3-O-glucoside, and cyanidin-3-O-rutinoside which are retained in the juice concentrate among other yet unidentified polyphenols.
Blackcurrant seed oil is also rich in many nutrients, especially vitamin E and several unsaturated fatty acids including alpha-linolenic acid and gamma-linolenic acid. In a human pilot study, ingestion of blackcurrant seed oil by mothers reduced atopic dermatitis in their breast-fed newborns who were supplemented with the oil over two years.
In the UK, blackcurrant cordial is often mixed with cider to make a drink called "Diesel" or "Snakebite and Black" available at pubs. Adding a small amount of blackcurrant juice to Guinness is preferred by some to heighten the taste of the popular stout. Macerated blackcurrants are also the primary ingredient in the apéritif crème de cassis. Japan imports $3.6 million in New Zealand blackcurrants for uses as dietary supplements, snacks, functional food products and as quick-frozen (IQF) produce for culinary production as jams, jellies or preserves. In Russia, blackcurrant leaves may be used for flavouring tea or preserves. Sweetened vodka may also be infused with blackcurrant leaves or berries, making a deep yellowish-green beverage with a sharp flavour and astringent taste. A universally sold drink, Ribena, is a juice drink made from blackcurrants which takes its name from Ribes.
Ribes nigrum, or Blackcurrant is a species of Ribes berry native to central and northern Europe and northern Asia and is a perennial.
It is a small shrub growing to 1–2 m tall. The leaves are alternate, simple, 3–5 cm long and broad, and palmately lobed with five lobes, with a serrated margin. The flowers are 4–6 mm diameter, with five reddish-green to brownish petals; they are produced in racemes 5–10 cm long.
When not in fruit, the plant looks similar to the redcurrant shrub, distinguished by a strong fragrance from leaves and stems. The fruit is an edible berry 1 cm diameter, very dark purple in colour, almost black, with a glossy skin and a persistent calyx at the apex, and containing several seeds dense in nutrients. An established bush can produce up to 5 kilograms of berries during summer.
Plants from Asia are sometimes distinguished as a separate variety, Ribes nigrum var. sibiricum, or even as a distinct species Ribes cyathiforme.
There are many cultivars of blackcurrant, including: Amos Black, Ben Alder, Ben Avon, Ben Connan, Ben Dorain, Ben Gairn, Ben Hope, Ben Lomond, Ben Loyal, Ben More, Ben Sarek, Ben Tirran, Big Ben, Boskoop Giant, Cotswold Cross and Wellington XXX.
New varieties are being developed continually to improve frost tolerance, disease resistance, machine harvesting, fruit quality, nutritional content and fruit flavour.
Varieties producing green fruit, less strongly flavoured and sweeter than typical blackcurrants, are cultivated in Finland, where they are called "greencurrants".