The Sweet Alternative
Stevia rebaudiana Bertoni
Chris Stothart
Stevia rebaudiana
Outline
 Overview
 Historical
Perspective
 Botany
 Ethnobotany
 Chemistry
 Extraction
& Commercial Uses
 Nutrition
 Regulation
 Controversies
 References
Stevia rebaudiana
Overview

Common names include: stevia, sweet leaf, sweet
herb of Paraguay, honey leaf, & sugar leaf

Increasing popularity of artificial sweeteners over the
past 20 years

Demand for “natural” & “healthier” alternatives

Perfect social, political, & economic climate

Widespread use as a non-nutritive sweetener due to
sweet leaves

Much debate over its use & health implications
Stevia rebaudiana
Historical Perspective
 Used
extensively by native cultures of South
America for centuries
 First
introduced to Europe by Spanish
conquistadores in 16th century
 Reintroduced
in early 20th century to scientific
community by Italian-Swiss botanist Dr. Moisés
S. Bertoni
 1905
– Bertoni classified & described stevia
Stevia rebaudiana
Historical Perspective cont.
 Since
1905 – Stevia has been widely studied
 Throughout
20th century sweet compounds in
leaves have been isolated, purified, patented,
& used in commercial products
 1970s
– Japan began using stevia in replace of
artificial sweeteners & sugar
 Largest
consumers: Japan, South Korea, Brazil,
& South America
Stevia rebaudiana
Botany
•
Tropical perennial &
herbaceous shrub
•
Native to Central & South
America
•
Member of Asteraceae
(Sunflower Family)
•
Grows 65-80 cm tall
•
Typically found in semi-dry
mountainous
environments & grasslands
•
Prefers well-drained nonsaline soil with pH 6.5-7.5
Stevia rebaudiana
Botany cont.
•
Simple, opposite green
sessile leaves
•
Stem, branches, &
leaves are all green &
are covered with short,
fine whitish hairs
•
All green parts taste
sweet
•
Inflorescences are tiny
white & purple disk
florets
•
Develop achene fruits
Stevia rebaudiana
Commercial cultivation
Paraguay, Brazil, Japan, China, Korea, Mexico, USA,
Indonesia, Tanzania, & Canada
Stevia rebaudiana
Ethnobotany
 Guarani
natives (Paraguay) credited with first
using the dried leaves to sweeten yerba mate
(Ilex paraguariensis) & chewed the fresh leaves
 Natives
used orally delivered concoctions as a
contraceptive, to manage diabetes, and to
treat stomach aches
 Caá
hê-é or Kaà heè, which in Guaraní, a local
dialect, translates into “sweet herb”
 Lack
of cultural & written records of stevia
Stevia rebaudiana
Ethnobotany cont.
3 explanations for limited historical record
1. Sweet-tasting properties were known since
the beginning of time, but kept a secret
2. Natives shared plant with Spaniards, but the
knowledge was disregarded or overlooked
3. Stevia’s potential as a sweetener was not
discovered by natives until only a short time
before European contact
Stevia rebaudiana
Chemistry
 Active
compounds: group of diterpene (steviol)
glycosides
 dulcoside
A, rebaudiosides A-E ,
steviolbioside, & stevioside
 Rebaudioside
A (3.8%) and stevioside (9.1%)
are the sweetest, most abundant, & most
important commercially
 Highest
yield of these compounds in leaves just
before the plant begins to flower,
Stevia rebaudiana
Chemical structures
Chemical structure of stevioside (left)
and rebaudioside A (right)
Stevia rebaudiana
Extraction & Commercial Uses
 Processing
of dried leaves from Stevia
produces a powdery white substance
(stevioside), which is three hundred times
sweeter, by weight, than sucrose derived from
sugar cane
 Water extraction process followed by
crystallization techniques to isolate the steviol
glycosides
 NRC has patent on nanofiltration techniques
commercially available stevia products:
stevioside and rebaudioside A include Truvia,
Fructevia, Krisda, & PureVia.
Stevia rebaudiana
Commercial products
Stevia rebaudiana
Nutrition
 The
dried leaves are 30 to 45 times as sweet as
sucrose
 Non-nutritive, three hundred times sweeter than
sugar, heat stable, non-fermentable, as well as
an anti-plaque and anti-carie
 More studies must be conducted on bulking
agents to make it easy to replace it for sugar
Stevia rebaudiana
Regulation
 Traditionally,
North America & EU have only
permitted use of highly purified extracts for sale
in health food stores & pharmacies
 Leaves
classified as a dietary supplement, but
not as a sweetener (Health Canada 2011)
 FDA
& Health Canada has approved use of
stevia derivatives as a sweetener in some
products (FDA 2011; Health Canada 2011)
 Marketed
as medicinal, non-medicinal
ingredients & for personal culinary use
Stevia rebaudiana
Controversies
 Few
conclusive results verifying negative health
claims
 Investigated effect of stevia on energy &
carbohydrate metabolism, on the
cardiovascular & renal systems, & reproduction
 Diabetes mellitus: helps with proper blood
glucose control, as antihyperglycemic by
stimulating the release of insulin, & to help
prevent insulin intolerance in diabetic patients
 Need for further clinical trials to ensure safety
of stevia for widespread human consumption
Stevia rebaudiana
Questions
Stevia rebaudiana
References
Goyal, S. K., Samsher, and Goyal, R.K. 2010. Stevia (Stevia rebaudiana) a bio-sweetener: a review. Intl. J. Food Sci. and Nutr. 61(1): 1-10.
Guens, J. C. 2003. Stevioside. Phytochemistry. 64(5): 913-921.
Health Canada. 2011. Frequently Asked Questions "FAQs" on Stevia [online]. Available from http://www.hc-sc.gc.ca/. [accessed 10 March
20111].
Huxtable, R. J. 2002. Pharmacology and toxicology of stevioside, rebaudioside A, and steviol. In Stevia: The genus Stevia. Edited by A.
Douglas Kinghorn. Taylor & Francis Inc, New York. pp. 160-177.
Jeppesen, P. B., Gregersen, S., Rolfsen, S. E. D., Jepsen, M., Colombo, M., Agger, A., Xiaso, J., Kruh, M., and Hermansen K. 2003.
Antihyperglycemic and blood pressure-reducing effects of stevioside in the diabetic Goto-Kakizaki rat. Metabolism. 52: 372-378.
Kinghorn, A. D. 2002. Overview. In Stevia: The genus Stevia. Edited by A. Douglas Kinghorn. Taylor & Francis Inc, New York. pp. 1-17.
Krisda Canada. Product Information [online]. Available from http://www.krisda.ca/. [accessed 10 March 2011].
Lewis, W. H. 1992. Early uses of Stevia rebaudiana (Asteraceae) leaves as a sweetener in Paraguay. Econ. Bot. 46: 336-340.
Madan, S., Ahmad, S., Singh, G. N., Kohli, K., Kumar, Y., Singh, R., and Gard, M. 2010. Stevia rebaudiana (Bert.) Bertoni – A Review. Ind. J. Nat.
Prod. 1(3): 267-286.
Rolfes, S. R., Pinna, K., and Whitney, E. 2009. Understanding Normal and Clinical Nutrition (8th ed.). Wadsworth, Cengage Learning, CA, USA.
pp. 136.
Samuelsson, G. 1992. Drugs of Natural origin. Swedish Pharmaceutical Press, Origin Stockholm Sweden.
Shi Qiu, Z., Ashwani, K., and Oleh, K. 2000. Membrane-based separation scheme for processing sweeteners from stevia leaves. Food Res. Int.
33: 617-620.
Soejartoa, D. D. 2002. Botany of Stevia and Stevia rebaudiana. In Stevia: The genus Stevia. Edited by A. Douglas Kinghorn. Taylor & Francis
Inc, New York. pp. 18-39.
Soejartob, D. D. 2002. Ethnobotany of Stevia and Stevia rebaudiana. In Stevia: The genus Stevia. Edited by A. Douglas Kinghorn. Taylor &
Francis Inc, New York. pp. 40-67.
Strauss, S. 1995. The perfect sweetner? Technol. Rev. 98: 18-20.
Sumida, T. 1980. Studies on Stevia rebaudiana Bertoni M, introduced from Brazil as a new sweetness resource in Japan. J. Cent. Agric. Exp.
Stn. 31: 1-71.
The National Geographic Society. 2008. Edible: An Illustrated Guide to the World’s Foods Plants. Global Book Publishing, Washington, DC. pp.
333.
United States Food and Drug Administration (FDA). 2011. What refined Stevia preparations have been approved by FDA to be used as a
sweetener? [online]. Available from http://www.fda.gov. [accessed 10 March 2011].
United States Patent and Trademark Office. 1998. United States Patent: 5,972,120 Extraction of sweet compounds from Stevia rebaudiana
Bertoni [online]. Available from http://patft.uspto.gov/. [accessed 10 March, 2011]
Wheeler, A., Boileau, A. C., Winkler, P. C., Compton, J. C., Prakash, I., Jiang, X., and Mandarino, D. A. 2008. Pharmacokinetics of
rebaudioside A and stevioside after single oral doses in healthy men. Food Chem. Toxi. 46: 54-60.