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STEVIOL GLYCOSIDES
(TENTATIVE)
Information required for commercially available products on • analytical data on distribution and concentrations of all component steviol glycosides, including those that are not identified in these tentative specifications • method of analysis for the determination of all component steviol glycosides, including those that are not identified in these tentativespecifications • the nature and concentration of the non-steviol glycosides fractions • the quantities of residual solvents from purification steps of the manufacturing process • the hydrolytic stability of the steviol glycosides in acidic foods and beverages New tentative specifications prepared at the 63rd JECFA (2004), published in FNP 52 Add 12 (2004). A temporary ADI of 0-2 mg/kg bw (expressedas steviol) was established at the 63rd JECFA (2004).

DEFINITION

Steviol glycosides are obtained by extracting leaves of Stevia rebaudiana Bertoni with hot water followed by solvent purification of the water-soluble extract. Ion exchange resins may also be used during the purification process. Stevioside and rebaudioside A are the principal steviol glycosides of the specified material.Rebaudioside C and dulcoside A are secondary steviol glycosides. Other steviol glycosides may also be present. The following are the chemical names for the principal and secondary steviol glycosides: Stevioside: 13-[(2-O-β–D-glucopyranosyl-β–D-glucopyranosyl) oxy] kaur16-en-18-oic acid β-D-glucopyranosyl ester Rebaudioside A: 13-[(2-O-β –D-glucopyranosyl-3-O-β–D-glucopyranosyl-β D-glucopyranosyl)oxy]kaur-16-en-18-oic acid β-D-glucopyranosyl ester Rebaudioside C: 13-[(2-O-α–L-rhamnopyranosyl-3-O-β–D-glucopyranosylβ-D-glucopyranosyl)oxy] kaur-16-en-18-oic acid β-D-glucopyranosyl ester Dulcoside A: 13-[2-O-α–L-rhamnopyranosyl-β–D-glucopyranosyl]oxy] kaur-16-en-18-oic acid β-D-glucopyranosyl ester

Chemical name

C.A.S. number

The following are the C.A.S. numbers for the principal andsecondary steviol glycosides: Stevioside: 57817-89-7 Rebaudioside A: 58543-16-1 Rebaudioside C: 63550-99-2 Dulcoside A: 64432-06-0 The following are the chemical formulas for the principal and secondary steviol glycosides: Stevioside: C38H60O18 Rebaudioside A: C44H70O23 Rebaudioside C: C44H70O22 Dulcoside A: C38H60O17 The following are the structural formulas for the principal and

Chemical formulaStructural formula

secondary steviol glycosides:
O-R2 CH3 CH2

CH3

COO-R1

Compound name Stevioside Rebaudioside A

R1

R2

β-Glc β-Glc

β-Glc-β-Glc(2→1) β-Glc-β-Glc(2→1)  β-Glc(3→1) β-Glc-α-Rha(2→1)  β-Glc(3→1) β-Glc-α-Rha(2→1)

Rebaudioside C

β-Glc

Dulcoside A

β-Glc

Steviol (R1 = R2 = H) is the aglycone of the steviol glycosides. Glc and Rha represent,respectively, glucose and rhamnose sugar moieties.
Formula weight

The following are the formula weights for the principal and secondary steviol glycosides: Stevioside: 804.88 Rebaudioside C: 951.03 Rebaudioside A: 967.03 Dulcoside A: 788.88 Not less than 95% of total steviol glycosides. The sum of the percentages of stevioside and rebaudioside A is not less than 70%. White crystalline powder,odourless or having a slight characteristic odour. About 200-300 times sweeter than sucrose.

Assay

DESCRIPTION

FUNCTIONAL USES Sweetener CHARACTERISTICS
IDENTIFICATION Solubility (Vol. 4) Stevioside and rebaudioside A PURITY Ash (Vol. 4)

Freely soluble in water and in ethanol The material contains not less than 70% of stevioside and rebaudioside A as identified and determined in the Methodof Assay. Not more than 1% Test 3 g of the sample (Method I)

Loss on drying (Vol. 4) Residual solvents Arsenic (Vol. 4) Lead (Vol. 4)

Not more than 4% (105°, 3h) Information required Not more than 1 mg/kg Not more than 1 mg/kg Determine using an atomic absorption technique appropriate to the specified level. The selection of sample size and method of sample preparation may be based on the...
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