Rooibos

Rooibos
Aspalathus linearis
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Rosids
Order: Fabales
Family: Fabaceae
Subfamily: Faboideae
Tribe: Crotalarieae
Genus: Aspalathus
Species: A. linearis
Binomial name
Aspalathus linearis
Flowers
Plant

Rooibos (/ˈrɔɪbɒs/ ROY-boss; Afrikaans: [rɔːibɔs]; Aspalathus linearis), meaning "red bush"; is a broom-like member of the Fabaceae family of plants growing in South Africa's fynbos.

The leaves are used to make a herbal tea that is called by the names: rooibos, bush tea (especially in Southern Africa), or redbush tea (predominantly in Great Britain). The tea has been popular in Southern Africa for generations, but is now consumed in many countries worldwide. It is sometimes spelled rooibosch in accordance with the original Dutch. The tea has a taste and color somewhat similar to hibiscus tea, or an earthy flavor like yerba mate.

The generic name comes from the Greek name aspalathos for Calicotome villosa, which has very similar growth and flowers to the rooibos plant. The specific name of linearis comes from the plant's linear growing structure and needle-like leaves.

Production and processing

Green rooibos tea
Rooibos tea in a glass
A rooibos-infused liqueur and rooibos tea

Rooibos is usually grown in the Cederberg, a small mountainous area in the region of the Western Cape province of South Africa.[2]

Generally, the leaves undergo an oxidation (often termed "fermentation" in common tea processing terminology). This process produces the distinctive reddish-brown colour of rooibos and enhances the flavour. Unoxidised "green" rooibos is also produced, but the more demanding production process for green rooibos (similar to the method by which green tea is produced) makes it more expensive than traditional rooibos. It carries a malty and slightly grassy flavour somewhat different from its red counterpart.[3]

Use

Rooibos tea is commonly prepared in the same manner as black tea and milk and sugar are added to taste. Other methods include a slice of lemon and using honey instead of sugar to sweeten. It is also served as espresso, lattes, cappuccinos or iced tea.[4]

Chemical composition

As a fresh leaf, rooibos contains a high content of ascorbic acid (vitamin C),[5] which is lost when made into tea.

Rooibos tea does not contain caffeine[6] and has low tannin levels compared to black tea or green tea.[5] Rooibos contains polyphenols, including flavanols, flavones, flavanones, dihydrochalcones,[7][8] aspalathin[9] and nothofagin.[10]

The processed leaves and stems contain benzoic and cinnamic acids.[11]

Grading

Rooibos grades are largely related to the percentage "needle" or leaf to stem content in the mix. A higher leaf content results in a darker liquor, richer flavour and less "dusty" aftertaste. The high-grade rooibos is exported and does not reach local markets, with major consumers being the EU, particularly Germany, where it is used in creating flavoured blends for loose-leaf tea markets.

History

In 1772, Swedish naturalist Carl Thunberg noted, "the country people made tea" from a plant related to rooibos or redbush. Traditionally, the local people would climb the mountains and cut the fine, needle-like leaves from wild rooibos plants. They then rolled the bunches of leaves into hessian bags and brought them down the steep slopes using donkeys. The leaves were then chopped with axes and bruised with hammers, before being left to dry in the sun.

Dutch settlers to the Cape learned to drink rooibos tea as an alternative to black tea, an expensive commodity for the settlers who relied on supply ships from Europe.

In 1904, Benjamin Ginsberg ran a variety of experiments at Rondegat Farm, finally curing rooibos. He simulated the traditional Chinese method of making Keemun by fermenting the tea in barrels. The major hurdle in growing rooibos commercially was that farmers could not germinate the rooibos seeds. The seeds were hard to find and impossible to germinate commercially.

In 1930 District Surgeon and botanist Dr Pieter Le Fras Nortier[12] began conducting experiments with the cultivation of the rooibos plant. Dr Nortier also saw the vast commercial potential the tea held for the region.

Dr Nortier cultivated the first plants at Clanwilliam on his farm Eastside and on the farm Klein Kliphuis. The tiny seeds were very difficult to come by. Dr Nortier paid the local villagers £5 per matchbox of seeds collected. An aged Khoi woman found an unusual seed source: having chanced upon ants dragging seed, she followed them back to their nest and, on breaking it open, found a granary.[12] Dr. Nortier's research was ultimately successful and he subsequently showed all the local farmers how to germinate their own seeds. The secret lay in scarifying the seed pods. Dr Nortier placed a layer of seeds between two mill stones and ground away some of the seed pod wall. Thereafter the seeds were easily propagated. Over the next decade the price of seeds soared to an astounding £80 a pound, the most expensive vegetable seed in the world, as farmers rushed to plant rooibos. Today, the seed is gathered by special sifting processes. Dr Nortier is today accepted as the father of the rooibos tea industry. Thanks to his research, rooibos tea became an iconic national beverage and then a globalised commodity. Rooibos tea production is today the economic mainstay of the Clanwilliam district. In 1948 The University of Stellenbosch awarded Dr Nortier an Honorary Doctorate D.Sc (Agria) in recognition for his valuable contribution to South African agriculture.

US trademark controversy

In 1994, Burke International registered the name "Rooibos" with the US Patent and Trademark Office, thus establishing a monopoly on the name in the United States at a time when it was virtually unknown there. When the plant later entered more widespread use, Burke demanded that companies either pay fees for use of the name, or cease its use. In 2005, the American Herbal Products Association and a number of import companies succeeded in defeating the trademark through petitions and lawsuits; after losing one of the cases, Burke surrendered the name to the public domain.[13]

The South African Department of Trade and Industry issued final rules on 6 September 2013 that protects and restricts the use of the names "rooibos", "red bush", "rooibostee", "rooibos tea", "rooitee" and "rooibosch" in that country, so that the name cannot be used for things not derived from the Aspalathus linearis plant. It also provides guidance and restrictions for how products which include Rooibos, and in what measures, should use the name "rooibos" in their branding.[14]

Threat from climate change

The rooibos plant is endemic to a small part of the western coast of the Western Cape province of South Africa. It grows in a symbiotic relationship with local micro-organisms. Scientists speculate that climate change may threaten the future survival of the plant and the R600-million (approximately €43-million in March 2017) rooibos industry. Some claim that increasing temperatures and decreasing rainfall may result in the extinction of the plant within the next century.[15]

See also

References

  1. ↑ "Aspalathus linearis (Burm.f.) R.Dahlgren". International Legume Database & Information Service (ILDIS). Retrieved 6 May 2016 – via The Plant List.
  2. ↑ Muofhe, M.L.; Dakora, F.D. (1999). "Nitrogen nutrition in nodulated field plants of the shrub tea legume Aspalathus linearis assessed using 15N natural abundance". Plant and Soil. 209 (2): 181–186. doi:10.1023/A:1004514303787.
  3. ↑ Standley, L; Winterton, P; Marnewick, JL; Gelderblom, WC; Joubert, E; Britz, TJ (January 2001). "Influence of processing stages on antimutagenic and antioxidant potentials of rooibos tea". Journal of Agricultural and Food Chemistry. 49 (1): 114–7. doi:10.1021/jf000802d. PMID 11170567.
  4. ↑ "Rooibos tea cappuccino or latte - Cape Point Press". Cape Point Press. 2014-03-06. Retrieved 2017-07-20.
  5. 1 2 Morton, Julia F. (1983). "Rooibos tea, aspalathus linearis, a caffeineless, low-tannin beverage". Economic Botany. 37 (2): 164–73. doi:10.1007/BF02858780. JSTOR 4254477.
  6. ↑ Iswaldi, I; Arráez-Román, D; Rodríguez-Medina, I; Beltrán-Debón, R; Joven, J; Segura-Carretero, A; Fernández-Gutiérrez, A (2011). "Identification of phenolic compounds in aqueous and ethanolic rooibos extracts (Aspalathus linearis) by HPLC-ESI-MS (TOF/IT)". Analytical and Bioanalytical Chemistry. 400 (10): 3643–54. doi:10.1007/s00216-011-4998-z. PMID 21509483.
  7. ↑ Krafczyk, Nicole; Woyand, Franziska; Glomb, Marcus A. (2009). "Structure-antioxidant relationship of flavonoids from fermented rooibos". Molecular Nutrition & Food Research. 53 (5): 635–42. doi:10.1002/mnfr.200800117. PMID 19156714.
  8. ↑ Quantitative Characterization of Flavonoid Compounds in Rooibos Tea (Aspalathus linearis) by LC-UV/DAD. Lorenzo Bramati, Markus Minoggio, Claudio Gardana, Paolo Simonetti, Pierluigi Mauri and Piergiorgio Pietta, J. Agric. Food Chem., 2002, volume 50, issue 20, pages 5513–5519, doi:10.1021/jf025697h
  9. ↑ Ku, S. K.; Kwak, S; Kim, Y; Bae, J. S. (2015). "Aspalathin and Nothofagin from Rooibos (Aspalathus linearis) inhibits high glucose-induced inflammation in vitro and in vivo". Inflammation. 38 (1): 445–55. doi:10.1007/s10753-014-0049-1. PMID 25338943.
  10. ↑ Joubert, E. (1996). "HPLC quantification of the dihydrochalcones, aspalathin and nothofagin in rooibos tea (Aspalathus linearis) as affected by processing". Food Chemistry. 55 (4): 403–411. doi:10.1016/0308-8146(95)00166-2.
  11. ↑ Rabe, C; Steenkamp, JA; Joubert, E; Burger, JF; Ferreira, D (1994). "Phenolic metabolites from rooibos tea (Aspalathus linearis)". Phytochemistry. 35 (6): 1559–1565. doi:10.1016/S0031-9422(00)86894-6.
  12. 1 2 Green, Lawrence (1949). In The Land of the Afternoon. Standard Press Ltd. pp. 52 to 54.
  13. ↑ "Rooibos Trademark Abandoned". American Herbal Products Association.
  14. ↑ "Merchandise Marks Act, 1941 (Act 17 of 1941), Final Prohibition on the Use of Certain Words]" (PDF). Department of Trade and Industry, Republic of South Africa. 6 September 2013. Retrieved 20 December 2014.
  15. ↑ "Climate change threatens rooibos". News24, IAB South Africa. 27 February 2012. Retrieved 27 April 2013.

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