RU2824047C1 - Steviol glycoside compositions - Google Patents

Abstract

FIELD: food industry.

SUBSTANCE: disclosed is a steviol glycoside composition containing mixture of 70/30 rebaudioside D and rebaudioside M, as well as minor steviol glycosides rebaudioside N and rebaudioside O. Each of the minor glycosides is present in the steviol glycoside composition in an amount of less than 5% by weight of the composition. Also disclosed is a steviol glycoside composition containing minor steviol glycosides, wherein the minor steviol glycosides include glycosylated rebaudioside Q and glycosylated rebaudioside R.

EFFECT: invention is aimed at obtaining steviol glycoside compositions having improved profiles of sweetness and taste.

7 cl, 7 dwg, 4 tbl, 4 ex

Description

LEVEL OF TECHNOLOGY

The invention is aimed at the positive effect of minor steviol glycosides on the sweetness profile of stevia-based sweeteners.

Sugar alternatives are receiving increasing attention due to awareness of the link between many health conditions and the consumption of foods and beverages high in sugar. However, many artificial sweeteners, such as dulcin, sodium cyclamate, and saccharin, have been banned or restricted in some countries due to safety concerns. For this reason, non-nutritive sweeteners of natural origin are becoming increasingly popular. The sweet-tasting herbaceous plant Stevia rebaudiana produces a series of diterpene glycosides that are characterized by high sweetness intensity and organoleptic properties superior to many other potent sweeteners.

Stevia rebaudiana is a plant species belonging to the Asteraceae family and is native to South America and is now grown in many countries worldwide (Gardana et al., 2003; Koyama et al., 2003; Carakostas et al., 2008). Stevia leaves are naturally sweet and have been used to sweeten foods for hundreds of years in South America (Soejarto et al., 1982). Stevia rebaudiana extracts have been used industrially to sweeten foods in Japan and other Southeast Asian countries for a number of years (Koyama et al., 2003). As a naturally occurring product, stevia plant leaves contain various sweet-tasting components called steviol glycosides. More than 40 steviol glycosides have been reported to be present in stevia leaf extract (Ceunen and Geuns, 2013; Chaturvedula et al., 2011a, b, c; Chaturvedula and Prakash, 2011a, b; Ohta et al., 2010). Each of the steviol glycosides has its own unique flavor profile and sweetness intensity, which can be up to 350 times sweeter than sugar, but they all have a similar molecular structure in which different sugar moieties are attached to the steviol aglycone (ent-kaurene diterpene). The general structure of the steviol glycosides is shown in Fig. 1.

Rebaudioside A and stevioside are of greatest commercial interest and have been extensively studied and characterized for their suitability as commercially available high-intensity sweeteners. Stability studies in carbonated beverages have confirmed their stability to heat and pH (Chang, S. S. and Cook, J. M. (1983) Stability studies of stevioside and rebaudioside A in carbonated beverages. J. Agric. Food Chem. 31: 409–412).

Steviol glycosides differ from each other not only in their molecular structure but also in their taste properties. As has been established, stevioside is usually 110-270 times sweeter than sucrose, and rebaudioside A is 150-320 times sweeter than sucrose. Rebaudioside A has the least astringent, least bitter and least persistent aftertaste, thus possessing the most favorable organoleptic properties among the main steviol glycosides (Tanaka O. (1987) Improvement of taste of natural sweeteners. Pure Appl. Chem.69:675-683; Phillips K. C. (1989) Stevia: steps in developing a new sweetener. In: Grenby T.H. ed. Developments in sweeteners, vol. 3. Elsevier Applied Science, London. 1-43).

By the beginning of the 21st century, only a limited number of chemical structures of steviol glycosides from Stevia rebaudiana plant had been described, including stevioside, rebaudioside AF, dulcoside A and steviolbioside (Ceunen and Geuns, 2013). In recent years, numerous minor steviol glycosides with different chemical structures have been described from the leaves of Stevia rebaudiana plant (Chaturvedula et al., 2011a, b, c; Chaturvedula and Prakash, 2011 a, b). These different steviol glycosides, which are ent-kaurene diterpenes, are linked to different sugars such as glucose, rhamnose, xylose, fructose and deoxyglucose at positions C-13 and C-19 1,2-; 1,3-; 1,4- or 1,6-α or β-glycosidic bonds. Identification features and classification into groups of different steviol glycosides are given in Table 1. Due to the large number of steviol glycosides, Table 1 provides 5 groups of steviol glycosides depending on the sugar moieties linked to the steviol framework and identified using abbreviated structural names.

The steviol glycoside family contains only steviol and glucose residues. This group can be represented by the general formula "SvGn", where Sv is steviol and G is glucose.

The steviol-rhamnoside family contains steviol, rhamnose and glucose residues. This group can be represented by the general formula "SvR1Gn", where R is rhamnose.

The steviol-xyloside family contains steviol, xylose and glucose residues. This group can be represented by the general formula "SvX1Gn", where X is xylose.

The steviol-fructoside family contains steviol, fructose and glucose residues. This group can be represented by the general formula "SvF1Gn", where F is fructose.

The steviol deoxyglucoside family contains steviol, deoxyglucose and a glucose residue. This group can be represented by the general formula SvdG1Gn.

Table 1.

No. Common name Abbreviated formula R ₁ R ₂ 1) Steviol + glucose (SvGn) 1.1 Steviol monoside SvG1 H Glcβ1- 1.2 Steviol-19-O-β-D-glucoside SvG1 Glcβ1- H 1.3 Rubusoside SvG2 Glcβ1- Glcβ1- 1.4 Steviolbioside SvG2 H Glcβ(1-2)Glcβ1- 1.5 Stevioside SvG3 Glcβ1- Glcβ(1-2)Glcβ1- 1.6 Stevioside A SvG3 Glcβ(1-2)Glcβ1- Glcβ1- 1.7 Rebaudioside B SvG3 H Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 1.8 Rebaudioside G SvG3 Glcβ1- Glcβ(1-3)Glcβ1- 1.9 Stevioside B SvG3 Glcβ(1-3)Glcβ1- Glcβ1- 1.10 Rebaudioside E SvG4 Glcβ(1-2) Glcβ1- Glcβ(1-2)Glcβ1- 1.11 Rebaudioside A SvG4 Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 1.12 Rebaudioside A2 SvG4 Glcβ1- Glcβ(1-6)Glcβ(1-2)Glcβ1- 1.13 Rebaudioside D SvG5 Glcβ(1-2)Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 1.14 Rebaudioside I SvG5 Glcβ(1-3) Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 1.15 Rebaudioside L SvG5 Glcβ1- Glcβ(1-6)Glcβ (1-2)[Glcβ(1-3)]Glcβ1- 1.16 Rebaudioside Q2 SvG5 Glcα(1-2)Glcα(1-4)Glcβ1- Glcβ(1-2)Glcβ1- 1.17 Rebaudioside Q SvG5 Glcβ1- Glcα(1-4)Glcβ (1-2)[Glcβ(1-3)]Glcβ1- 1.18 Rebaudioside I2 SvG5 Glcβ1- Glcα(1-3)Glcβ (1-2)[Glcβ(1-3)]Glcβ1- 1.19 Rebaudioside Q3 SvG5 Glcβ1- Glcα(1-4)Glcβ (1-3)[Glcβ(1-2)]Glcβ1- 1.20 Rebaudioside I3 SvG5 Glcβ(1-2)[Glcβ (1-6)]Glcβ1- Glcβ(1-2)Glcβ1- 1.21 Rebaudioside M SvG6 Glcβ(1-2)[Glcβ (1-3)]Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 2) Steviol+rhamnose+glucose (SvR1Gn) 2.1 Dulcoside A SvR1G2 Glcβ1- Rhaα(1-2)Glcβ1- 2.2 Dulcoside B SvR1G2 H Rhaα(1-2)[Glcβ (1-3)]Glcβ1- 2.3 Rebaudioside C SvR1G3 Glcβ1- Rhaα(1-2)[Glcβ (1-3)]Glcβ1- 2.4 Rebaudioside C (isomer) SvR1G3 Rhaα(1-2)Glcβ1- Glcβ(1-3)Glcβ1- 2.5 Rebaudioside H SvR1G4 Glcβ1- Glcβ(1-3)Rhaα (1-2)[Glcβ(1-3)]Glcβ1- 2.6 Rebaudioside K SvR1G4 Glcβ(1-2)Glcβ1- Rhaα(1-2)[Glcβ (1-3)]Glcβ1- 2.7 Rebaudioside J SvR1G4 Rhaα(1-2)Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 2.8 Rebaudioside N SvR1G5 Rhaα(1-2)[Glcβ (1-3)]Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 2.9 Rebaudioside O SvR1G6 Glcβ(1-3)Rhaα (1-2)[Glcβ(1-3)]Glcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1- 3) Steviol+xylose+glucose (SvX1Gn) 3.1 Stevioside F SvX1G2 Glcβ1- Xylβ(1-2)Glcβ1- 3.2 Rebaudioside F SvX1G3 Glcβ1- Xylβ(1-2)[Glcβ (1-3)]Glcβ1- 3.3 Rebaudioside F2 SvX1G3 Glcβ1- Glcβ(1-2)[Xylβ (1-3)]Glcβ1- 3.4 Rebaudioside F3 SvX1G3 Xylβ(1-6)Glcβ1- Glcβ(1-2)Glcβ1- 4) Steviol+fructose+glucose (SvF1Gn) 4.1 Rebaudioside A3 SvF1G3 Glcβ1- Glcβ(1-2)[Fruβ (1-3)]Glcβ1- 5) Steviol+deoxyglucose+glucose (SvdG1Gn) 5.1 Stevioside D SvdG1G2 Glcβ1- 6-deoxyGlcβ(1-2)Glcβ1- 5.2 Stevioside E SvdG1G3 Glcβ1- 6-deoxyGlcβ(1-2)[Glcβ(1-3)] Glcβ1- 5.3 Stevioside E2 SvdG1G3 6-deoxyGlcβ1- Glcβ(1-2)[Glcβ (1-3)]Glcβ1-

ESSENCE OF THE INVENTION

The present invention is directed to improving the sweetness profile of steviol glycosides sweeteners such as stevioside and rebaudioside A (Reb A). Surprisingly, it has been discovered that certain minor steviol glycosides have a beneficial effect on the sweetness profile of other steviol glycosides, including rebaudioside D (Reb D) and rebaudioside M (Reb M). These minor steviol glycosides, despite being present in small amounts, show a statistically significant positive effect on the sweetness profile of stevia-based sweeteners. As used herein, a "minor steviol glycoside" is a steviol glycoside that is present in a composition in an amount of less than 5% or less than 3%.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows the general structure of steviol glycosides.

Figure 2a shows the structure of rebaudioside N. Figure 2b shows the structure of rebaudioside O.

Fig. 3a shows a histogram showing the results of the organoleptic evaluation by the tasting panel. The first columns show the results of tasting the composition of highly purified (at least 97% pure) rebaudioside A in acidified water. The second columns show the results of tasting the composition of fructosylated rebaudioside A in acidified water.

Fig. 3b is a histogram showing the results of the sensory evaluation by the panel of tasters. The first columns show the results of tasting the diet lemon-lime carbonated soft drink containing the highly purified Reb M/Reb D mixture, where the mixture comprises 50 wt.% Reb M and 50 wt.% Reb D. The second columns show the results of tasting the diet lemon-lime carbonated soft drink containing the fructosylated rebaudioside A composition.

Fig. 4a is a histogram showing the results of the organoleptic evaluation by the tasting panel. The first columns display the results of tasting the composition of highly purified (at least 97% pure) rebaudioside A in acidified water. The second columns display the results of tasting the composition of glycosylated minor steviol glycoside in acidified water, where the composition of glycosylated minor steviol glycoside includes 19 wt.% glycosylated Reb Q and 18 wt.% glycosylated Reb R.

Fig. 4b is a histogram showing the results of an organoleptic evaluation by a taste panel. The first columns display the results of tasting a diet lemon-lime carbonated soft drink containing a highly purified Reb M/Reb D mixture, wherein the mixture comprises 50 wt.% Reb M and 50 wt.% Reb D. The second columns display the results of tasting a diet lemon-lime carbonated soft drink containing a glycosylated minor steviol glycoside composition in acidified water, wherein the glycosylated minor steviol glycoside composition comprises 19 wt.% glycosylated Reb Q and 18 wt.% glycosylated Reb R.

DETAILED DESCRIPTION OF THE INVENTION

Steviol glycoside compositions including minor glycosides (SG compositions) such as rebaudioside N and rebaudioside O have been found to have a positive effect on the sweetness profile of stevia-based sweeteners. An exemplary steviol glycoside composition is described in Table 2.

Table 2.

Steviol glycoside composition (SG composition)

Molecules Structure Steviol glycoside composition Reb D SvG5 63.95 Reb M SvG6 25.37 Reb N SvR1G5 2.95 Reb O SvR1G6 1.37 Reb A SvG4 1.32 Reb E SvG4 0.86 Reb B SvG3 0.22 Stevioside SvG3 0.03 Reb C SvR1G3 0.01 Reb F SvX1G3 0 Dulcoside A SvR1G2 0 Rubusoside SvG2 0 Steviolbioside SvG2 0 Total amount of steviol glycosides 96.07

Comparison of Reb D/Reb M mixtures with steviol glycoside compositions

EXAMPLE 1. Acidified water - set value 5 Brix

15 tasters evaluated the test solutions as shown in Table 3:

Table 3.

Acidified water with a specified value of 5 Brix - SG composition compared to Reb D and Reb M mixtures

Summary of means, p-values and significance Property 5% sugar SG composition 200 ppm Mixture 70/30 Reb D/Reb M 200 ppm P-value Significance Sweetness 4.91 4.86 4.98 0.0997 Bitterness b
0.75 ab
0.98 a
1.23 0,0083 *** Astringency b
0.84 b
1.02 a
1.77 0.0035 *** Acidity c
0.99 b
1.41 a
1.99 0,0012 *** Foreign taste (metallic/licorice) b
0.52 b
0.61 a
1.13 0,0081 *** Sweet aftertaste c
0.56 b
0.99 a
1.38 0,0046 *** Bitter aftertaste 0.33 0.37 0.53 0.5487 insignificant Overall attractiveness a
4.96 b
4.53 b
4.46 0,1964 *

*=80% confidence interval, **=90% confidence interval, ***=95% confidence interval

As can be seen, the steviol glycoside composition (SG composition) has many properties that are closer to a 5% sugar solution than the Reb D/Reb M blends, and the overall appeal is higher than the Reb D/Reb M blends. The steviol glycoside composition with minor glycosides and the 70/30 Reb D/Reb M blend had similar sweetness levels. The 70/30 Reb D/Reb M blend had significantly higher astringency, acidity, off-flavors, and sweet aftertaste compared to the SG composition. The two samples have significantly different flavor profiles.

EXAMPLE 2. Acidified water - set value 10 Brix

The same test was carried out as in Example 1, but with a target value of 10 Brix. 13 tasters assessed the solutions as shown in Table 4:

Table 4.

Acidified water with a target value of 10 Brix - SG composition compared to Reb D and Reb M mixtures

Summary of means, p-values and significance Property 10% sugar SG composition 900 ppm Mixture 70/30 Reb D/Reb M 900 ppm P-value Significance Sweetness 8.45 8.62 8.45 0.8794 insignificant Bitterness b
0.55 a
2.18 a
1.72 0,0147 *** Astringency b
0.92 a
1.55 a
1.71 0.0762 ** Acidity b
1.08 a
1.56 a
1.61 0,0508 ** Foreign taste (metallic/licorice) b
0.51 a
1.11 a
1.34 0.0028 *** Sweet aftertaste c
1.08 b
1.75 a
2.25 0.0029 *** Bitter aftertaste b
0.37 a
0.62 a
0.82 0,0464 *** Overall attractiveness a
6.34 b
4.6 b
4.65 0.0091 ***

*=80% confidence interval, **=90% confidence interval, ***=95% confidence interval

In this test, the steviol glycoside composition and the Reb D/Reb M blend had similar levels of sweetness. The 70/30 blend also had a significantly stronger sweet aftertaste compared to the steviol glycoside composition.

Without being bound by any theory, it is believed that rebaudioside N and rebaudioside O, present in minor amounts in the steviol glycoside composition, have a beneficial effect on the flavor and sweetness profiles of the steviol glycoside composition, particularly at a target value of 5 Brix. The structures of rebaudioside N and rebaudioside O are shown in Fig. 2a and 2b. However, some benefits were observed even at a target value of 10 Brix, making these minor steviol glycosides suitable for improving sweetness profiles.

EXAMPLE 3. Fructosylated steviol glycosides

It has been found that the addition of one or more fructose molecules to rebaudioside A provides advantages in flavor and sweetness profiles. It is believed that fructosylation of rebaudioside A or other steviol glycosides, including minor steviol glycosides, can provide characteristics that are similar to or even better than highly purified steviol glycosides. Rebaudioside A was subjected to a glycosylation process with the addition of fructose at the G1 and G2 positions and compared with a highly purified rebaudioside A composition in acidified water and a highly purified Reb M/Reb D mixture in a diet lemon-lime carbonated soft drink. The results of the sensory evaluation by a trained taste panel are shown in Figs. 3a and 3b.

EXAMPLE 4. Glycosylated minor steviol glycosides

It has been found that in addition to their beneficial effects on the flavor and sweetness profiles of steviol glycoside compositions, the effects of minor glycosides can be enhanced by glycosylation. Glycosylated steviol glycosides (GSG) have one or more glycoside moieties attached to the steviol glycoside backbone and have been found to have a beneficial effect on properties such as bitterness, sweet aftertaste, etc., of steviol glycoside compositions. Glycosylated minor steviol glycosides can improve the flavor and sweetness profiles of steviol glycoside compositions to produce similar or even superior flavor and sweetness profiles to highly purified steviol glycosides, thus providing an effective and productive alternative to highly purified steviol glycosides.

The glycoside moiety may be any monosaccharide, disaccharide or oligosaccharide such as glucose, fructose, rhamnose, xylose and the like. The glycoside moiety may be a single molecule or may be a chain of molecules such as 2, 3 or 4 glucose molecules attached to a steviol glycoside. The glycosylation process typically results in the attachment of the glycoside moiety at the C-13 or C-19 position to the steviol glycoside.

In one embodiment, the composition of rebaudioside A and a minor steviol glycoside is glycosylated. The minor steviol glycoside composition comprises about 19 wt.% glycosylated rebaudioside Q and about 18 wt.% glycosylated rebaudioside R.

Samples of acidified water and diet lemon-lime carbonated soft drink containing varying amounts of the glycosylated minor steviol glycoside composition were evaluated by a panel of tasters and the results are shown in Figures 4a and 4b. As can be seen, the composition containing the glycosylated minor steviol glycoside performed nearly as well as, and in some cases better than, the highly purified steviol glycoside compositions (Reb A and Reb M/Reb D) on a number of sweetness and flavor attributes.

It should be understood that the above description and specific embodiments are merely illustrative of the best mode of the invention and its principles, and that modifications and additions can be easily made by those skilled in the art without departing from the spirit and scope of the invention, which is intended to be limited only by the scope of the appended claims.

Claims (7)

1. A steviol glycoside composition containing a 70/30 mixture of rebaudioside D and rebaudioside M, additionally containing the minor steviol glycosides rebaudioside N and rebaudioside O, wherein each of the minor glycosides is present in the steviol glycoside composition in an amount of less than 5% by weight of the composition. 2. A steviol glycoside composition comprising minor steviol glycosides, wherein the minor steviol glycosides comprise glycosylated rebaudioside Q in an amount of about 19% and glycosylated rebaudioside R in an amount of about 18%. 3. The composition according to claim 1, wherein at least one minor steviol glycoside is glycosylated. 4. The composition according to claim 1, wherein the minor steviol glycosides provide taste properties: astringency, acidity, off-flavor, bitter aftertaste and sweet aftertaste, which are closer to a sugar solution than to a comparative mixture of rebaudioside D and rebaudioside M. 5. The composition of claim 1, wherein the mixture with minor glycosides provides a sweetness profile closer to a 5 Brix solution than mixtures without minor glycosides. 6. The composition of claim 1, wherein the mixture with minor glycosides has less astringency, less acidity, less off-flavor, less sweet aftertaste, and less bitter aftertaste than the mixture without minor glycosides, relative to a 10 Brix solution. 7. The composition according to claim 1, wherein each of the minor glycosides is present in the steviol glycoside composition in an amount of less than 3% by weight of the composition.