High-purity rebaudioside D and low-calorie tooth paste composition containing the same

1. A low-calorie tooth paste composition, comprising:

a natural sweetener composition comprising Rebaudioside D in the range of 81-96 wt %, Rebaudioside A in the range of 3-16 wt %, Stevioside in the range of 0.1-0.8 wt %, Rebaudioside C in the range of 0.1-0.7 wt %, Rebaudioside E in the range of 0.2-0.5 wt %, Rebaudioside F in the range of 0.1-0.2 wt %;

calcium phosphate,

carboxymethylcellulose;

carrageenan;

glycerol;

polyoxyethylene sorbitan mono-ester;

beta-cyclodextrin;

sodium laurylsarcosinate;

flavoring; and

preservative;

whereby all components are mixed with water so as to form the low-calorie tooth paste composition.

2. The low-calorie tooth paste composition of claim 1 , wherein the flavoring includes mint, apple, strawberry and vanilla.

3. The low-calorie tooth paste composition of claim 1 , wherein

the natural sweetener composition in the range of 0.01-0.2% (w/w);

the calcium phosphate in the range of 30-60% (w/w);

the carboxymethylcellulose in the range of 1.0-2.0% (w/w);

the carrageenan in the range of 0.2-0.8% (w/w);

the glycerol in the range of 10-25% (w/w);

the polyoxyethylene sorbitan mono-ester in the range of 1-3% (w/w);

the beta-cyclodextrin in the range of 1-2% (w/w);

the sodium laurylsarcosinate in the range of 0.1-0.3% (w/w);

the flavoring in the range of 0.5-2% (w/w); and

preservative in the range of 0.05-0.2% (w/w).

4. The low-caloric tooth paste composition of claim 1 , wherein the natural sweetener composition is obtained from Stevia rebaudiana Bertoni plant by a method comprising the following steps:

a) providing an extract of Stevia rebaudiana Bertoni plant;

b) dissolving the extract in a first aqueous solution of organic solvent to result in a first mixture of steviol glycosides, wherein the organic solvent is selected from the group consisting of methanol, ethanol, 1-propanol, isopropanol, and a mixture thereof, and the organic solvent is 75-99 vol. %;

c) inducing crystallization in the first mixture;

d) filtering the mixture from step (c) to obtain a first precipitate and a first filtrate;

e) dissolving the first precipitate in a second aqueous solution of organic solvent to result in a second mixture, wherein the organic solvent is selected from the group consisting of methanol, ethanol, 1-propanol, isopropanol, and a mixture thereof and the organic solvent is 70-80 vol. %;

f) inducing crystallization in the second mixture;

g) filtering the mixture from step (f) to obtain a second precipitate and a second filtrate;

h) dissolving the second precipitate in a third aqueous solution of organic solvent to result in a third mixture, wherein the organic solvent is selected from the group consisting of methanol, ethanol, 1-propanol, isopropanol, and a mixture thereof, and the organic solvent is 10-80 vol. %;

i) inducing crystallization in the third mixture; and

j) filtering the mixture from step (i) to obtain a third precipitate and a third filtrate;

whereby the third precipitate is dried to yield the natural sweetener composition.