Stevia

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For other uses, see Stevia (disambiguation).

Stevia (/ˈstvɪə/, /ˈstvjə/ or /ˈstɛvɪə/)[1][2][3][4] is a sweetener and sugar substitute made from the leaves of the plant species Stevia rebaudiana. Stevia's taste has a slower onset and longer duration than that of sugar, and some of its extracts may have a bitter or licorice-like aftertaste at high concentrations.

With its steviol glycoside extracts having up to 300 times the sweetness of sugar,[5] stevia has attracted attention with the rise in demand for low-carbohydrate, low-sugar sweeteners. Because stevia has a negligible effect on blood glucose it is attractive to people on carbohydrate-controlled diets.

The availability of stevia varies from country to country. In a few countries, it has been available as a sweetener for decades or centuries; for example, it has been widely used for decades as a sweetener in Japan. In some countries health concerns and political controversies have limited its availability; for example, the United States banned stevia in the early 1990s unless labeled as a dietary supplement,[6][7] but since 2008 it has accepted several specific glycoside extracts as being generally recognized as safe for use as food additives. Over the years, the number of countries in which stevia is available as a sweetener has been increasing. In 2011, stevia was approved for use in the EU.[8][9]

History and use[edit]

The plant Stevia rebaudiana has a long history of ethnomedical use by the Guaraní, having been used extensively by them for more than 1,500 years.[10] The leaves have been traditionally used for hundreds of years in both Brazil and Paraguay to sweeten local teas and medicines, and as a "sweet treat".[10]

Steviol is the basic building block of stevia's sweet glycosides.

In 1899 Swiss botanist Moisés Santiago Bertoni, while conducting research in eastern Paraguay, first described the plant and the sweet taste in detail.[11] Only limited research was conducted on the topic until in 1931 two French chemists isolated the glycosides that give stevia its sweet taste.[12] These compounds, stevioside and rebaudioside, are 250–300 times as sweet as sucrose and are heat-stable, pH-stable, and not fermentable.[5]

The exact structure of the aglycone and the glycoside was published in 1955.

In the early 1970s, sweeteners such as cyclamate and saccharin were suspected of being carcinogens. Consequently, Japan began cultivating stevia as an alternative. The plant's leaves, as well as the aqueous extract of the leaves and purified steviosides, were developed as sweeteners. The first commercial stevia sweetener in Japan was produced by the Japanese firm Morita Kagaku Kogyo Co., Ltd. in 1971.[13] The Japanese have been using stevia in food products and soft drinks, (including Coca Cola), and for table use. Japan currently consumes more stevia than any other country, with stevia accounting for 40% of the sweetener market.[14]

In the mid 1980s, stevia began to become popular in U.S. natural foods and health food industries, as a non-caloric natural sweetener for teas and weight-loss blends.[15][16] The makers of the synthetic sweetener NutraSweet asked the FDA to require testing of the herb.[16]

Today, Stevia rebaudiana is cultivated and used to sweeten food in East Asia including Japan, China (since 1984), Korea, Taiwan, Thailand, and Malaysia. It can also be found in Saint Kitts and Nevis, Brazil, Colombia, Peru, Paraguay, Uruguay, and Israel. China is the world's largest exporter of stevioside.[14]

Stevia rebaudiana plants which are found in the wild in semiarid habitats ranging from grassland to mountain terrain, do produce seeds, but only a small percentage of the seeds germinate. Planting cloned stevia is a more effective method of reproduction.[citation needed]

Folk medicine[edit]

For centuries, the Guaraní peoples of Paraguay used Stevia rebaudiana, which they called ka'a he'ê ("sweet herb"), as a sweetener in yerba mate and other foods, and as a medicinal agent.[citation needed]

Availability[edit]

The Stevia rebaudiana plant may be grown legally in most countries, although some countries restrict its use as a sweetener.
Stevia tablets as widely sold in health food stores in Germany
Widely used as a sweetener
Available as a food additive (Regulatory agency approved)
  • Australia, and New Zealand (October 2008)[18] – All steviol glycoside extracts
  • Brazil (1986)[17] – Stevioside extract
  • Hong Kong (steviol glycosides, January 2010)[19]
  • Israel (January 2012)[20]
  • Mexico (2009)[17] – mixed steviol glycoside extract, not separate extracts
  • Norway (June 2012) As food additive[21] – E 960 Steviol glycoside. The plant itself has not been approved as of September 2012
  • Russian Federation (2008) – stevioside is allowed in the "minimal dosage required" to achieve the goal of the additive.[22]
  • Singapore (2005) steviol glycosides are a permitted sweetening agent in certain foods.[23] Previously it was banned.[24]
Available as both a food additive and dietary supplement
  • Canada (November 2012)
    • Steviol glycosides became available as a food additive on 30 November 2012.[25]
    • Stevia rebaudiana leaf and extracts are available as dietary supplements
  • European Union – Steviol glycosides have been permitted as a food additive since 2 December 2011.[8][9][17][26][27]
  • United States (December 2008)
    • Rebaudioside A is available (December 2008) as a food additive (sweetener)[28] sold under various trade names.
    • Stevia rebaudiana leaf and extracts are available as dietary supplements (1995)
  • Indonesia (2012)
    • Steviol glycosides are available under the Regulation of Minister of Health No. 033 year 2012 on Food Additives[29])
    • Stevia leaf is available as a dietary supplement
Available (regulatory status unverified)
Stevia extract on sale in a supermarket in Paraguay

Availability notes[edit]

Commercialization[edit]

Steviol glycosides were first commercialized as a sweetener in 1971 by the Japanese firm Morita Kagaku Kogyo Co., Ltd., a leading stevia extract producer in Japan.

Stevia rebaudiana has been grown on an experimental basis in Ontario, Canada since 1987 to determine the feasibility of commercial cultivation.[32] Duke University researchers developed a strategic plan to assist farmers and exporters in Paraguay to compete in the global market for stevia.[33]

In 2007 The Coca-Cola Company announced plans to obtain approval for their stevia-derived sweetener, rebiana, for use as a food additive within the United States by 2009, as well as plans to market rebiana-sweetened products in 12 countries that allow stevia's use as a food additive.[34][35] In May 2008 Coca Cola and Cargill announced the availability of Truvia, a consumer brand stevia sweetener containing erythritol and rebiana,[36] which the FDA permitted as a food additive in December 2008.[37] Coca-Cola announced intentions to release stevia-sweetened beverages in late December 2008.[38]

Shortly afterward, PepsiCo and Pure Circle announced PureVia, their brand of stevia-based sweetener, but withheld release of beverages sweetened with rebaudioside A until receipt of FDA confirmation. Since the FDA permitted Truvia and PureVia, both Coca Cola and PepsiCo have introduced products that contain their new sweeteners.[39]

Extraction of sweet compounds[edit]

Rebaudioside A has the least bitterness of all the steviol glycosides in the Stevia rebaudiana plant. To produce rebaudioside A commercially, stevia plants are dried and subjected to a water extraction process. This crude extract contains about 50% rebaudioside A; its various glycoside molecules are separated via crystallization techniques, typically using ethanol or methanol as solvent. This allows the manufacturer to isolate pure rebaudioside A.[40]

The National Research Council of Canada has patented a process for extracting sweet compounds from stevia by column extraction at temperatures from 0 to 25 °C, followed by purification by nanofiltration. A microfiltration pretreatment step is used to clarify the extract. Purification is by ultrafiltration followed by nanofiltration.[41]

Mechanism of action[edit]

Glycosides are molecules that contain glucose and other non-sugar substances called aglycones (molecules with other sugars are polysaccharides). The tongue's taste receptors react to the glucose in the glycosides – those with more glucose (rebaudioside) taste sweeter than those with less (stevioside).[42] Some of the tongue's bitter receptors react to the aglycones.

In the digestive tract, rebaudiosides are metabolised into stevioside. Then stevioside is broken down into glucose and steviol. The glucose released in this process is used by bacteria in the colon and not absorbed into the bloodstream.[43] Steviol cannot be further digested and is excreted.

Safety[edit]

Steviol and rebaudioside A are not mutagenic at doses and routes of administration at which humans are exposed to them.[44][45][46] Two 2010 review studies found no health concerns with stevia or its sweetening extracts.[47][48]

The WHO's Joint Experts Committee on Food Additives has approved, based on long-term studies, an acceptable daily intake of steviol glycoside of up to 4 milligrams per kilogram of body weight.[49]

While the FDA does not consider whole-leaf Stevia or crude Stevia extracts to be "generally recognized as safe" ("GRAS") food additives,[50] several companies have submitted notices to the FDA that they consider specific rebaudiosides to be GRAS for use as food additives, and have had these notices accepted by the FDA.[51]

The European Food Safety Authority evaluated the safety of steviol glycosides, extracted from the leaves of the Stevia rebaudiana Bertoni plant, as sweetener and expressed its opinion on 10 March 2010. The Authority established an Acceptable Daily Intake (ADI) for steviol glycosides, expressed as steviol equivalents, of 4 mg/kg bodyweight/day. On 11 November 2011, the European Commission allowed the usage of steviol glycosides as a food additive, establishing maximum content levels for different types of foods and beverages.[52]

Potential health effects[edit]

A 2009 review study found that stevioside and related compounds may have anti-hyperglycemic, anti-hypertensive, anti-inflammatory, anti-tumor, anti-diarrheal, diuretic, and immunomodulatory actions.[53] A 2011 review found that the use of stevia sweeteners as replacements for sugar would likely benefit diabetic patients.[47] Furthermore, the report noted "stevioside has shown some evidence of pharmacological effects in patients with hypertension or with diabetes mellitus type 2,"[44] but concluded further study was required to determine proper dosage.

Controversy[edit]

In 1991, after receiving an anonymous industry complaint, the United States Food and Drug Administration (FDA) labeled stevia as an "unsafe food additive" and restricted its import.[31][54][55] The FDA's stated reason was "toxicological information on stevia is inadequate to demonstrate its safety."[56]

Since the import ban in 1991, marketers and consumers of stevia have shared a belief that the FDA acted in response to industry pressure.[31] Arizona congressman Jon Kyl, for example, called the FDA action against stevia "a restraint of trade to benefit the artificial sweetener industry".[57] To protect the complainant, the FDA deleted names in the original complaint in its responses to requests filed under the Freedom of Information Act.[31]

Stevia remained banned until after the 1994 Dietary Supplement Health and Education Act forced the FDA in 1995 to revise its stance to permit stevia to be used as a dietary supplement, although not as a food additive – a position that stevia proponents regarded as contradictory because it simultaneously labels stevia as safe and unsafe, depending on how it is sold.[6]

Early studies prompted the European Commission in 1999 to ban stevia's use in food in the European Union pending further research.[58] In 2006, research data compiled in the safety evaluation released by the World Health Organization found no adverse effects.[44] Since 2008, the Russian Federation has allowed stevioside as a food additive "in the minimal dosage required".[22]

In December 2008, the FDA gave a "no objection" approval for GRAS status to Truvia (developed by Cargill and The Coca-Cola Company) and PureVia (developed by PepsiCo and the Whole Earth Sweetener Company, a subsidiary of Merisant), both of which use rebaudioside A derived from the Stevia plant.[59] However, FDA said that these products are not Stevia, but a highly purified product.[60] In 2012, FDA posted a note on their website regarding crude Stevia plant: "FDA has not permitted the use of whole-leaf Stevia or crude Stevia extracts because these substances have not been approved for use as a food additive. FDA does not consider their use in food to be GRAS in light of reports in the literature that raise concerns about the use of these substances. Among these concerns are control of blood sugar and effects on the reproductive, cardiovascular, and renal systems."[61]

See also[edit]

References[edit]

  1. ^ "Stevia". Merriam-webster.com. 31 August 2012. Retrieved 13 February 2013. 
  2. ^ "Stevia". British & World English. Oxforddictionaries.com. 7 February 2013. Retrieved 13 February 2013. 
  3. ^ "Stevia". US English. Oxforddictionaries.com. 7 February 2013. Retrieved 13 February 2013. 
  4. ^ Both /ˈstvɪə/ and /ˈstɛvɪə/ are recorded by at least some US and UK dictionaries, but the former is more common in US English (listed first or exclusively) and the latter is more common in UK English.
  5. ^ a b Raji Akintunde Abdullateef, Mohamad Osman (1 January 2012). "Studies on effects of pruning on vegetative traits in Stevia rebaudiana Bertoni (Compositae)". International Journal of Biology 4 (1). doi:10.5539/ijb.v4n1p146. 
  6. ^ a b McCaleb, Rob (1997). "Controversial Products in the Natural Foods Market". Herb Research Foundation. Retrieved 8 November 2006. 
  7. ^ "Dietary Supplement Health and Education Act of 1994". fda.gov. 2011. Retrieved 31 January 2011. 
  8. ^ a b Lucas, Louise (2011). "Brussels backs Stevia sweetener". Financial Times. Retrieved 22 November 2011. 
  9. ^ a b Stones, Mike (2011). "Stevia wins final EU approval". foodmanufacture.co.uk. Retrieved 22 November 2011. 
  10. ^ a b Misra, H.; Soni, M.; Silawat, N.; Mehta, D.; Mehta, B. K.; Jain, D. C. (April 2011). "Antidiabetic activity of medium-polar extract from the leaves of Stevia rebaudiana Bert. (Bertoni) on alloxan-induced diabetic rats". J Pharm Bioallied Sci 3 (2): 242–8. doi:10.4103/0975-7406.80779. PMC 3103919. PMID 21687353. 
  11. ^ Bertoni, Moisés Santiago (1899). Revista de Agronomia de l'Assomption 1: 35. 
  12. ^ Bridel, M.; Lavielle, R. (1931). "Sur le principe sucre des feuilles de kaa-he-e (stevia rebaundiana B)". Academie des Sciences Paris Comptes Rendus (Parts 192): 1123–5. 
  13. ^ "Stevia". Morita Kagaku Kogyuo Co., Ltd. 2004. Retrieved 6 November 2007. 
  14. ^ a b Jones, Georgia (September 2006). "Stevia". NebGuide: University of Nebraska–Lincoln Institute of Agriculture and Natural Resources. Retrieved 4 May 2007. 
  15. ^ Zeavin, Edna. "The Outlaw Herbal Sweetener". East West Journal. February 1988. p. 28. "Stevia, also called sweet leaf or sweet herb, is making inroads into the health food and natural foods markets."
  16. ^ a b Keville, Kathi. "Exploring South America's Medicinal Plants". Vegetarian Times. April 1987. p. 47.
  17. ^ a b c d "Truvia timeline". Archived from the original on 1 January 2010. 
  18. ^ "Stevia gets Australian approval for food and beverages". Foodnavigator.com. Retrieved 13 February 2013. 
  19. ^ "Cap 132U Schedule (Sweeteners in Food Regulations; Public Health and Municipal Services Ordinance) |". legislation.gov.hk. 2011. Retrieved 22 June 2011. 
  20. ^ "Stevia Sweeteners Now Approved in Israel". greenprophet.com. 2012. Retrieved 5 April 2012. 
  21. ^ "Norwegian Stevia fact sheet Norwegian Institute of Public Health". Fhi.no. 17 June 1999. doi:10.2903/j.efsa.2010.1537. Retrieved 13 February 2013. 
  22. ^ a b "Technical regulations for juice products from fruits and vegetables". Russian Federation Federal Law. 27 October 2008. p. Table 5. 
  23. ^ "Sale of Food Act, Chapter 283, Section 56(1) – Food Regulations". Agri-Food & Veterinary Authority of Singapore. 2005. 
  24. ^ Li, Simon (27 March 2002). Fact Sheet: Stevioside (PDF). Hong Kong Legislative Council Secretariat Research and Library Services Division. 
  25. ^ "Notice of Modification to the List of Permitted Sweeteners to Enable the Use of Steviol Glycosides as a Table-Top Sweetener and as a Sweetener in Certain Food Categories - Document Reference Number NOM/ADM-0002". Health Canada. 2012. 
  26. ^ Halliday, Jess (8 September 2009). "France approves high Reb A stevia sweeteners". foodnavigator.com. Retrieved 23 January 2010. 
  27. ^ Halliday, Jess (15 September 2009). "France's first stevia products around the corner". foodanddrinkeurope.com. Retrieved 23 January 2010. 
  28. ^ a b c Curry,Leslie Lake. "Agency Response Letter GRAS Notice No. GRN 000287". Retrieved 28 August 2010. 
  29. ^ http://usdaindonesia.org/wp-content/uploads/2012/08/permenkes-033-2012-translation.pdf
  30. ^ a b c "Olam and Wilmar in 50:50 JV to Acquire 20% Stake in PureCircle, a Leading Producer of Natural High-Intensity Sweeteners for USD 106.2 Mln". flex-news-food.com. 1 July 2008. Retrieved 5 April 2012. 
  31. ^ a b c d Hawke, Jenny (February–March 2003). December 2010 "The Bittersweet Story of the Stevia Herb" (PDF). Nexus magazine 10 (2). Retrieved 20 December 2010. 
  32. ^ Todd J (2010). "The Cultivation of Stevia, "Nature's Sweetener"". Ontario Ministry of Agriculture and Food. Retrieved 20 March 2014. 
  33. ^ Bamber, P; Fernandez-Stark, K (2012). "Strengthening the competitiveness of the stevia value chain in Paraguay". Duke University Center on Globalization, Governance and Competitiveness. Retrieved 20 March 2014. 
  34. ^ Stanford, Duane D. (31 May 2007). "Coke and Cargill teaming on new drink sweetener". Atlanta Journal-Constitution. Archived from the original on 30 September 2007. Retrieved 31 May 2007. 
  35. ^ Etter, Lauren and McKay, Betsy (31 May 2007). "Coke, Cargill Aim For a Shake-Up In Sweeteners". Wall Street Journal. Retrieved 1 June 2007. 
  36. ^ "Truvia ingredients". Retrieved 15 May 2008. 
  37. ^ "Stevia sweetener gets US FDA go-ahead". Decision News Media SAS. 18 December 2008. Retrieved 11 May 2009. 
  38. ^ "Coke to sell drinks with stevia; Pepsi holds off". The Seattle Times. Associated Press. 15 December 2008. Retrieved 16 December 2008. 
  39. ^ "FDA Approves 2 New Sweeteners". The New York Times. Associated Press. 17 December 2008. Retrieved 11 May 2009. 
  40. ^ Purkayastha, S. ""A Guide to Reb-A", Food Product Design". Retrieved 28 March 2009. 
  41. ^ "United States Patent 5,972,120 Extraction of sweet compounds from Stevia rebaudiana Bertoni". 
  42. ^ Growing Stevia, Retrieved 7 November 2013
  43. ^ Koyama, E., et al. "In vitro metabolism of the glycosidic sweeteners, stevia mixture and enzymatically modified stevia in human intestinal microflora." Food and Chemical Toxicology 41.3 (2003) 359–374.
  44. ^ a b c Benford, D. J.; DiNovi, M.; Schlatter, J. (2006). "Safety Evaluation of Certain Food Additives: Steviol Glycosides" (PDF). WHO Food Additives Series (World Health Organization Joint FAO/WHO Expert Committee on Food Additives (JECFA)) 54: 140. 
  45. ^ Geuns JM (2003). "Stevioside". Phytochemistry 64 (5): 913–21. doi:10.1016/S0031-9422(03)00426-6. PMID 14561506. 
  46. ^ Brusick DJ (2008). "A critical review of the genetic toxicity of steviol and steviol glycosides". Food Chem Toxicol 46 (7): S83–S91. doi:10.1016/j.fct.2008.05.002. PMID 18556105. 
  47. ^ a b Goyal, S. K.; Samsher; Goyal, R. K. (February 2010). "Stevia (Stevia rebaudiana) a bio-sweetener: a review". Int J Food Sci Nutr 61 (1): 1–10. doi:10.3109/09637480903193049. PMID 19961353. 
  48. ^ Ulbricht, C.; Isaac, R.; Milkin, T.; Poole, E. A.; Rusie, E. et al. (April 2010). "An evidence-based systematic review of stevia by the Natural Standard Research Collaboration". Cardiovasc Hematol Agents Med Chem 8 (2): 113–27. PMID 20370653. 
  49. ^ Joint FAO/WHO Expert Committee on food additives, Sixty-ninth Meeting. World Health Organization. 4 July 2008. 
  50. ^ FDA Page updated 4 April 2012 Is Stevia an 'FDA approved' sweetener?
  51. ^ FDA GRAS notification database Stevia search in FDA GRAS Database Accessed 20 March 2014
  52. ^ "Commission Regulation (EU) No 1131/2011" (PDF). Official Journal of the European Union: 7. 11 November 2011. Retrieved 15 November 2011. "The CE regulation establishes steviol glycosides as food additive, and establishes maximum content levels in foodstuff and beverages." 
  53. ^ Chatsudthipong, V.; Muanprasat, C. (January 2009). "Stevioside and related compounds: therapeutic benefits beyond sweetness". Pharmacol Ther 121 (1): 41–54. doi:10.1016/j.pharmthera.2008.09.007. PMID 19000919. 
  54. ^ "Celestial Seasonings: Who sent the trade complaint that started the raid?".  – memorandum from the Department of Health & Human Services to its Denver office.
  55. ^ "Artificial Sweetener Controversies From Saccharin to Sucralose". leda.law.harvard.edu. 20 December 2010. Retrieved 20 December 2010. 
  56. ^ Food and Drug Administration (1995, rev 1996, 2005). Import Alert #45-06: "Automatic Detention of Stevia Leaves, Extract of Stevia Leaves, and Food Containing Stevia"
  57. ^ Kyl, John (R-Arizona) (1993). Letter to former FDA Commissioner David Aaron Kessler about the 1991 stevia import ban, quoted at stevia.net safety studies.
  58. ^ European Commission Scientific Committee on Food (June 1999). Opinion on Stevioside as a Sweetener
  59. ^ Newmarker, Chris (18 December 2008). "Federal regulators give OK for Cargill's Truvia sweetener". Minneapolis / St. Paul Business Journal. Retrieved 18 December 2008. 
  60. ^ "What refined Stevia preparations have been evaluated by FDA to be used as a sweetener?". fda.gov. U.S. Food and Drug Administration. Retrieved 22 March 2014. 
  61. ^ "Is Stevia an 'FDA approved' sweetener?".