Stevia:
Functional Food used as a Low
Calorie Alternative Sweetener
Research Paper
Emily Brantley
February 24, 2011
FOS 4041
Professor Ross
Introduction
In the past decade there has been an outburst of research and production
of foods created with Stevia increased development of consumer food products
that are sweetened with Stevia. Stevia is used as a functional food to sweeten a
diverse variety of food consumer products. Some of these products include fruit
juices, soda beverages, yogurts, ice creams, cereals and baked goods.
Understanding the advantages and disadvantages of Stevia is significant
because excessive sugar intakes have become a major health concern here in
America. Approximately two thirds of American adults are currently overweight
or obese. This means that the majority of our society is at risk for a high number
of precarious health conditions with the two most severe being Type 2 Diabetes
Mellitus and heart disease (1). The major culprit along with solid fats is a surplus
of sugar, which on average provides 35 percent, or nearly 800 calories per
person, per day (2). These disproportionate amounts create elevated levels of at
risk members in our society. Staggering statistics like this have jumpstarted a
Stevia phenomenon. There is a fundamental need for an alternative sweetener
in place of sugar, or other chemical sweeteners. Stevia is getting more
recognition than ever before as a functional food and a natural alternative to
sugar to decrease or avoid these health risks altogether.
The Stevia Rebaudiana (Bertoni) plant produces hydrophilic, sweet
glycosides derived from its leaves. This shrub like plant belongs to the
Chrysanthemum Family and it is native to South America in Paraguay and parts
of Brazil. Although it has existed in this region for hundreds of years, the
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biosynthesis of its steviol glycosides has only been researched and published
within the last forty years (3). One of the notable advantages of Stevia extract is
its powerful sweet flavor. In fact, only a small amount is necessary for the
purpose of sweetening because it is 250 to 300 times sweeter than sucrose.
Another favorable factor is its low calorie nature (4 & 5). This is beneficial for
people who have excess sugar in their diet or for those who merely wish to cut
back on sugar consumption. Stevia, when used as a functional food in place of
sugar, can be used without the usual restrictions and recommended to the
diabetic population especially since it is scientifically proven as ineffective to a
person’s glucose levels (6).
By examining the chemical composition, health benefits, flavor, absorption
rate and marketing targets of Stevia, the purpose of this research paper is to
explore the recent magnification of Stevia, a functional food ingredient used as
an alternative to sugar, or other low calorie chemical sweeteners.
Chemical Composition of Stevia
As previously mentioned, Stevia is extracted from the Stevia Rebaudiana
(Bertoni) plant. The chemical structure of Stevia leaves consists of glycosides, or
combination of a non-carbohydrate group and an attached sugar. “All are
glycosides of the common aglycone, or non-carbohydrate group, steviol. They
differ in the number (typically three to five) and type of sugars attached” (7). In
its leaves, there are nine to ten different steviol glycosides found that are
accessible for extraction (8). Of those ten, Stevioside and Rebaudioside A are
the only two major sweet tasting steviol glycosides that are used by food
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manufacturers as a functional food component. But these steviol glycosides are
not suitable to be added to food products in the raw leaf form. Rather, a refining
procedure is necessary to generate a highly purified component of the Stevia
leaves that is smoothly added to food products.
In the first step, Stevia leaves are harvested and dried. Then the
glycosides are extracted by steeping the dried leaves in hot water, a process
much similar to the procedure used for tealeaf extraction. Next, the purification
portion of the method begins when the Stevia extract is dissolved in ethanol
and/or methanol where it crystallizes and is then filtered. An activated carbon is
used to lighten the crystallized glycosides to a desired white or off white colored
powder, closely resembling granulated sugar. The concentrate is finally dried
and what remains is a high purity form of the essential Stevia extracts, Stevioside
or Rebaudioside A (9).
The finished refined product is a decolorized, purified and crystallized
form of Stevia. And, it is freely soluble in water thus making it acceptable and
suitable to add into consumer food products. The Generally Recognized as Safe
(GRAS) policy makers recognizes five appropriate and acceptable highly refined
preparations for Stevia in food products. Among them are McNeil Nutritionalswho produce Sun crystals, Cargill- the manufacturers of Truvia and Whole Earth
Sweetener/Merisant-the creators of PureVia (10).
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The Use of Stevia as a Functional Food
From the shocking American health demographics, there comes an
obvious consumer demand for lower calorie, safe tabletop “fake sugars.” Stevia
is the newcomer to the industry, which is already thriving with aspartame, and
sucralose. Like its fellow alternative sweeteners, Stevia offers a powerful
sweetness without excess calories (4). But the main advantage that Stevia has
over other sweeteners is that it originated from a plant rather than a chemical.
Marketers have caught on to that fact and used it to their gain by pushing Stevia
as the only “natural” alternative sweetener. They even back up this concept by
using green packaging as opposed to the competition packet colors in pink, blue
or yellow (NY TIMES).
With that in mind, it is easy to see Stevia’s appeal to an open spectrum of
food manufacturers. One physical characteristic of Stevia is that it is more stable
in acidic beverages than other widely used sweeteners. By means of that
advantage, Stevia is more than sufficient for the commercial production of soft
drinks (7 on outline). Studies conducted by Cargill and Marisant have even
revealed that the storage life of rebaudioside A in a carbonated citric acid
beverage and a phosphoric acid beverage did not significantly degrade during
prolonged storage at refrigeration, normal ambient, or elevated ambient
temperatures. (GRAS)
In terms of satisfactoriness when Stevia is used as to replace some or all
of the sugar in a recipe, studies show that the recipe does not drastically affect
the visual acceptability or physical characteristics of a food product (11 outline).
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In one test where chocolates sweetened with stevioside were compared to
conventional and commercial chocolates, there was no significant difference in
acceptability (9 outline). And then in a double blind taste test involving baked
goods, such as a cake, a cookie and shortbread, completely replacing sugar with
Stevia demonstrated a different flavor with a mild variation in volume tenderness
and texture. However, the overall product was generally accepted and satisfying
(10 outline). There is an obvious recognition expansion for Stevia to be used as
a functional food ingredient.
But even with the rapid popularity growth, Stevia’s journey into our food
products has not gone without controversy. For many years it was only permitted
in America for use in dietary supplements. Steviol glycosides were approved to
be used as a functional ingredient in dietary supplements since the Dietary
Supplement Health and Education Act (DSHEA) passed in the United States in
1994 (Williams LD). At that time however, neither the extract nor any kind of
refined component of Stevia was considered unobjectionably safe to be used in
foods or beverages sold other than as a dietary supplement (CLOS JF).
Although America was developing toleration for Stevia, in 2000 the European
Commission refused to reason Stevia or stevioside as a novel food ingredient
simply because there wasn’t enough critical scientific research reports. Among
the various cited studies that did exist at the time, there were inconvenient
discrepancies regarding possible toxilogical effects of the consumption of
stevioside (4). On the other hand, in Southeast Asia in places like Japan, Korea
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and China, Stevia and its refined components are recognized and sold as an
acceptable sweetener (DE MELO9 on outline)
The FDA’s response to the GRAS notice on Stevia and Stevia refined
products was labeled as pending until September 9, 2009 (9). On that date, the
case was closed and Stevia was accepted as safe for “scientific procedures,
general-purpose sweetener in foods, excluding meat and poultry products, at
levels determined by current good manufacturing practices.” After a great length
of controversy, the FDA concluded, “there is no basis to object to the use of
certain refined Stevia preparations in food. These refined Stevia preparations
may be lawfully marketed and added to food products sold in the United States”
(10).
Conclusion
With its overall flavor acceptability and stability, I believe the use of Stevia
as a functional food ingredient has a valuable future. It may have taken a long
time for many countries to decide, but today, throughout the world, Stevia has
certainly earned the right to be considered a safe, natural sugar substitute and
alternative sweetener. In my opinion, I believe that Stevia shows concrete
rewards in the future treatment of type 2 Diabetes Mellitus. And with ongoing
research and experiments, the applications of Stevia as a functional ingredient
are immeasurable.
Application to Dietary Practice
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Having a comprehensive knowledge of Stevia based research is
applicable to dietary practice in a variety of ways. Its advantages and drawbacks
would clearly affect a great population being that currently, two thirds of adult
Americans are overweight thus being at risk for a number of different harmful
health conditions (1). With that being said, choosing Stevia offers a valuable
alternative way to fight against those harmful health conditions like Obesity and
Type 2 Diabetes Mellitus. What’s more, Stevia can be used as a substitute
sweetener that provides powerful sweetness without raising blood sugar levels
and without excess calories. For that reason, it can especially be recommended
by dietitians to these two risk groups to help diminish their existence in our
American population.
The “fake sugar” industry has reached $1.2 billion-a-year. Newcomer
Stevia has a distinct advantage to marketers; it comes from a plant so it can be
marketed as a natural sweetener (NY Times). There are a variety of foods that
have started to use Stevia Rebaudiana as a functional food ingredient because it
is considered a natural sugar alternative. Stevia is appealing to many consumers
and its popularity is growing along with the magnified competitive marketing of
different sweeteners to the diabetic community. In addition, the popularity of
Stevia is on the rise since the position of the American Dietetic Association holds
that nonnutritive sweeteners, like Stevia, can safely be enjoyed by consumers
when consumed in a diet that is guided by existing federal nutrition suggestions
such as the Dietary References Intakes (2).
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The list of products containing Stevia as a functional food ingredient is
rather broad ranging from ice cream all the way to sports drinks. When
compared to the price of sugar, the prices of crystallized packaged sweeteners
made with Stevia are priced higher, but not priced impractically or unaffordable to
most. For example, one hundred packets of sugar costs $1.69 whereas one
hundred packets of PureVia, a crystallized form of Stevia extract, costs $3.29. It
is almost impossible to overlook the fact that most of products using Stevia are
sweet flavored beverages or beverage enhancers. This is undoubtedly due to
the overwhelming demand of sweet drinks in America. At a whopping 36%,
soda, energy drinks and sports drinks are the biggest source of added sugars in
the diets of the U.S. Population for persons two years of age and older (Dietary
Guidelines). These beverages range in price from under two dollars to almost
seven dollars.
When all is said and done, the use of Stevia as a functional food
ingredient to sweeten and Stevia based research both prove very beneficial to
dietetic practice. Selecting Stevia in place of sugar or a chemical sweetener
demonstrates how a slight alteration in a person’s diet can drastically change
their health risk.
In fact, “replacing intake of added sugars with nonnutritive
sweeteners could result in a deficit of 380 cal/day or 1 pound of weight loss in 9
to 10 days, if intake was at 95 g (24 tsp) daily” (8 Position of JADA). Stevia has
the potential of altering the health risk demographics in America.
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Below is a list of products that contain Stevia available to consumers
found at Publix Super Market: 731 Duval Station Rd Jacksonville FL 32218
Product Name
Description
Truvia
Crystallized, Refined Stevia
rebaudiana Extract
Crystallized, Refined Stevia
rebaudiana Extract
Crystallized, Refined Stevia
rebaudiana Extract
Combination of Sugar and
Refined Stevia Extract
Functional water beverage
Functional water beverage
Juice
PureVia
Stevia in the Raw
Sun crystals
Glaceau Vitamin Water Zero
0 Calorie SoBe Life Water
Minute Maid Enhanced
Pomegranate Tea
Crystal Light Pure Fitness
Odwalla Juice
Powerade PLAY
Powdered water
supplement.
Organic juice product
Sports Drink
Cost
$6.29 for 80 packets;
$3.99 for 40 packets
$3.29 for 100 packets;
$1.99 for 40 packets
$3.59 for 50 packets;
$6.99 for 9.7 oz
$3.59 for 50 packets
$1.49 each; $5.99 for 4
$1.59 each
$3.69
$3.49
$2.99
Usually 4 for $5, Sale Price
10 for $10
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