When ingredient buyers specify “stevia extract,” they’re rarely buying a single compound. The dried leaf of Stevia rebaudiana Bertoni holds a complex mixture of diterpene glycosides — collectively, steviol glycosides — of which stevioside is the most abundant and most commercially significant. Telling apart the plant, the extract class, and the individual glycosides is foundational for any specification decision at scale.
This article covers what stevioside is at the molecular level, how it relates to the other glycosides in the leaf, what commercial grade specifications mean in practice, and what current research says about its functional and safety profile.
The Stevia Leaf: A Complex Mixture of Glycosides
Stevia rebaudiana Bertoni is a small perennial shrub in the Asteraceae family, native to Paraguay and grown commercially across China, India, Kenya, and South America. Its sweetness comes from a family of structurally related diterpene glycosides — compounds built on the same steviol aglycone backbone but differing in the number and arrangement of attached sugar units. More than 40 steviol glycosides have been identified in the leaf, though only a handful occur at commercially relevant concentrations.[1]
The four major glycosides in a standard leaf profile are stevioside, rebaudioside A (Reb A), rebaudioside C, and dulcoside A. Stevioside dominates, typically 5–10% of the leaf’s dry weight depending on cultivar and growing conditions; Reb A follows at 2–4%, with Reb C and dulcoside A lower. Minor glycosides — rebaudioside B, D, E, F, M, and rubusoside — appear in trace amounts; some, particularly rebaudioside M, draw strong commercial interest for their superior sensory properties despite low natural abundance.[2]
| Glycoside | Typical Leaf Content (dry weight) | Sweetness vs. Sucrose | Sensory Notes |
|---|---|---|---|
| Stevioside | 5–10% | 150–300× | Bitter/licorice aftertaste at high dose |
| Rebaudioside A | 2–4% | 250–450× | Cleaner than stevioside, mild aftertaste |
| Rebaudioside C | 1–2% | 50–120× | Slightly bitter |
| Dulcoside A | 0.3–0.5% | 50–120× | Bitter |
| Rebaudioside M | Trace (<0.1%) | 200–350× | Clean, closest to sucrose profile |
| Rubusoside | Trace | ~115× | Mild bitterness |
The commercial value of any stevia-derived ingredient depends on which glycoside is specified and at what purity. “Stevia extract” as a generic term spans everything from crude dried-leaf powder to highly purified Reb M isolates — a range that makes ingredient-level specification essential wherever consistency matters.
Stevioside: Molecular Structure and Chemical Identity
Stevioside belongs to the diterpene glycoside class of compounds. Its structure is a steviol aglycone backbone — a tetracyclic diterpene derived from the ent-kaurane skeleton — with two glucose-containing sugar chains: a sophorose unit at C-13 and a single glucose at C-19 (the carboxyl position).
The steviol backbone is the element shared by all steviol glycosides — a rigid, multi-ring framework that gives the compound its stability across temperature and pH. What varies between glycosides is the sugar substitution: stevioside carries a disaccharide at C-13 and a monosaccharide at C-19, while Reb A carries a trisaccharide at C-13 (one additional glucose), which accounts for its cleaner taste relative to stevioside.
| Parameter | Stevioside | Rebaudioside A | Rebaudioside M |
|---|---|---|---|
| Molecular Formula | C₃₈H₆₀O₁₈ | C₄₄H₇₀O₂₃ | C₅₆H₉₀O₃₃ |
| Molecular Weight (g/mol) | 804.87 | 967.01 | 1291.30 |
| CAS Number | 57817-89-7 | 58543-16-1 | 1220616-44-3 |
| Sugar units at C-13 | Disaccharide (sophorose) | Trisaccharide | Trisaccharide |
| Sugar units at C-19 | Monosaccharide (glucose) | Monosaccharide (glucose) | Trisaccharide |
| Sweetness vs. Sucrose | 150–300× | 250–450× | 250–300× |
| Sensory Profile | Bitter/licorice aftertaste | Clean, mild aftertaste | Closest to sucrose, no aftertaste |
Commercial Grades and Purity Specifications
Steviol glycoside extracts sell in a range of standardized grades, differentiated by total steviol glycoside content and, within that, by the proportion of specific glycosides. What these grades mean for formulation performance and cost-in-use drives procurement decisions — see our stevia extract grades for current specifications.
| Grade | Total Steviol Glycosides | Stevioside Content | Typical Applications |
|---|---|---|---|
| Stevioside 80% (GSG 80%) | ≥80% | ~65–75% | Industrial food processing, baked goods, sauces, condiments |
| Stevioside 90% | ≥90% | ~75–85% | Functional beverages, dairy, dietary supplements |
| Stevioside 95% | ≥95% | ~85–90% | Pharmaceutical excipients, pediatric formulations, premium nutraceuticals |
| Reb A 97% | ≥97% (Reb A) | Minimal | Premium beverages, clean-label products, applications requiring minimal aftertaste |
| Reb M 95% | ≥95% (Reb M) | Minimal | Premium zero-sugar products, sucrose-profile replacement, next-generation formulations |
For most high-volume food manufacturing — baked goods, condiments, dairy, and industrial beverage bases — GSG 80% (stevioside-dominant) is the cost-optimal specification. Its lower purification requirement relative to high-purity Reb A grades translates directly to lower raw-material cost per unit of sweetness, and the bitter aftertaste, while present, is manageable through masking agents and flavor modulation.
Where aftertaste is a primary consumer-facing concern — premium beverages, direct-consumption supplements, or products without the flavor complexity to mask bitterness — higher-purity Reb A 97% or Reb M 95% become the appropriate specification despite higher cost. The grade decision is fundamentally a cost-vs-sensory trade-off calibrated to the application.
Stability Properties: Why Stevioside Performs Under Demanding Conditions
Stevioside’s tetracyclic diterpene backbone gives it strong resistance to degradation under the thermal and pH conditions of commercial food and beverage processing. Published data indicates it maintains chemical integrity at up to 120°C for one hour and performs consistently across pH 2–10 — a window covering carbonated soft drinks (pH 3–4), dairy (pH 6–7), and baked goods at oven temperatures.[3]
This compares favorably to certain other natural sweetener systems. Some minor steviol glycosides and enzymatically modified compounds show measurable degradation under prolonged heat, requiring formulators to adjust processing or add stabilizers. Stevioside’s resilience in high-acid and thermally demanding applications removes that complexity in most standard production environments.
Water solubility is adequate for most aqueous applications — about 0.13 g/mL at room temperature, improving at elevated temperatures, which suits standard beverage dissolution. Its non-hygroscopic powder form supports conventional packaging and storage without special moisture control.
Functional and Biomedical Properties
Beyond sweetness delivery, the published research on stevioside covers several areas of functional activity relevant to nutraceutical and pharmaceutical positioning.
Glycemic Safety and Metabolic Profile
Stevioside is non-nutritive and non-cariogenic — it doesn’t contribute to dental caries and isn’t metabolized for caloric energy in the conventional sense. In the gut, it’s hydrolyzed by intestinal microbiota to release steviol, which is then absorbed, conjugated, and excreted without accumulation. This clean metabolic pathway underpins the US FDA GRAS designation for high-purity steviol glycosides and the EFSA acceptable daily intake of 4 mg/kg body weight (as steviol equivalents).[4]
Research has also examined stevioside’s potential direct contribution to glycemic management. Some studies report modest effects on insulin secretion and glucose uptake at pharmacological concentrations, but the evidence remains primarily preclinical, and the effect at typical dietary exposure isn’t considered clinically significant. For products positioned in the blood-sugar-management category, the more defensible claim rests on stevioside’s role as a zero-calorie sucrose replacement, not on direct pharmacological activity.
Antioxidant Activity
Steviol glycosides, including stevioside, show measurable free-radical scavenging in standard in vitro assays. A review published in Molecules confirmed that stevioside and Reb A carry antioxidant properties alongside their sweetening function — a dual utility behind their adoption in nutraceutical formulations.[1] The practical significance in finished products depends on the concentration used and the formulation matrix, and in vitro values should not be extrapolated to in vivo claims.
Pharmaceutical Applications
Stevioside’s combination of high sweetness intensity, thermal stability, zero caloric value, and established safety makes it a workable excipient in oral pharmaceutical formulations — particularly pediatric syrups, chewable tablets, and oral suspensions where palatability affects patient compliance. Its stability across the pH range relevant to oral dosage forms (pH 2–8) avoids the formulation complications that arise with less stable sweeteners in medicated liquids.
Stevioside vs. Rebaudioside A: The Practical Formulation Decision
The choice between stevioside-dominant and Reb A-dominant extracts is the most frequent specification decision in steviol glycoside procurement. It’s primarily a matter of cost versus sensory performance, not safety or regulatory status — both are covered under the GRAS designation for steviol glycosides.
Stevioside is the economically dominant option wherever flavor masking is feasible or the matrix has enough complexity to absorb the bitter aftertaste — low-pH carbonated beverages, high-fat dairy, and baked goods all perform well commercially at lower cost. Reb A is preferred where the product is relatively simple in flavor and bitterness would be perceptible without mitigation. Reb M, while superior in sensory terms, carries a cost premium reflecting its low natural abundance and more demanding purification.[2] For a side-by-side breakdown across taste, stability, and cost, see rebaudioside A vs stevia.
Formulation Usage Guide: Steviol Glycosides by Application
The following guide is for food and beverage formulators working with steviol glycoside ingredients. Addition levels are expressed as total steviol glycosides per kilogram of finished product and align with the maximum use levels in major frameworks including GB 2760 (China), EU Regulation (EC) No 1333/2008, and FDA GRAS notices. Grade selection follows the sensory and cost considerations outlined above.
Beverages
| Application | Recommended Level (g/kg) | Recommended Grade | Formulation Notes |
|---|---|---|---|
| Carbonated soft drinks | 0.18–0.25 | Reb A 97% or Reb M 95% | Low pH (3–4) enhances sweetness perception; aftertaste more noticeable in still vs. carbonated; consider citric acid co-addition for flavor rounding |
| Flavored water / sports drinks | 0.18–0.22 | Reb A 97% or Reb M 95% | Simple matrix with no fat to mask aftertaste; Reb M preferred for clean label premium positioning |
| Fruit juice beverages | 0.20–0.27 | Reb A 97% or GSG 80% | Natural fruit acids aid masking; GSG 80% acceptable in high-flavor-intensity products such as tropical or citrus variants |
| Tea and coffee drinks (RTD) | 0.20–0.25 | Reb A 97% | Tannins in tea and coffee provide bitterness masking that makes Reb A workable; avoid GSG 80% in mild green tea variants |
| Plant-based / oat milk drinks | 0.18–0.23 | Reb A 97% or Reb M 95% | Fat content aids aftertaste masking; Reb M preferred where sucrose-mimic positioning is a label claim |
Dairy Products
| Application | Recommended Level (g/kg) | Recommended Grade | Formulation Notes |
|---|---|---|---|
| Flavored yogurt | 0.20–0.25 | Reb A 97% or GSG 80% | Lactic acid and fat content provide strong masking; GSG 80% is cost-effective here |
| Flavored milk / drinking yogurt | 0.18–0.23 | Reb A 97% or GSG 80% | Dairy fat and protein buffer bitterness effectively; vanilla and chocolate variants tolerate GSG 80% well |
| Ice cream and frozen desserts | 0.20–0.27 | Reb A 97% | High fat content is excellent for aftertaste masking; note that cold temperature reduces sweetness perception — calibrate at service temperature |
| Cheese and fermented dairy | 0.09–0.15 | GSG 80% | Low addition levels required; complex flavor matrix tolerates GSG 80% without sensory penalty |
Bakery and Confectionery
| Application | Recommended Level (g/kg) | Recommended Grade | Formulation Notes |
|---|---|---|---|
| Bread and plain baked goods | 0.4–0.5 | GSG 80% | Stevioside is thermally stable to 120°C; Maillard reaction products in baked goods provide substantial bitterness masking; GSG 80% is the standard specification for cost efficiency |
| Cakes and sweet pastries | 0.4–0.5 | GSG 80% or Reb A 97% | Higher fat and egg content aids masking; note that stevioside does not provide the bulking or tenderizing function of sucrose — use bulking agents (erythritol, inulin) to compensate |
| Biscuits and cookies | 0.4–0.5 | GSG 80% | Low water activity and high-fat matrix tolerate GSG 80% without sensory issues; chocolate coatings further mask residual bitterness |
| Candy and hard confectionery | 0.27–0.33 | Reb A 97% | Concentrated sugar matrix: even small amounts of bitterness are amplified; Reb A preferred; fruit acid inclusion (citric, malic) aids sweetness rounding |
| Chocolate and cocoa products | 0.23–0.27 | GSG 80% or Reb A 97% | Cocoa’s natural bitterness masks stevioside aftertaste effectively; dark chocolate variants tolerate GSG 80% |
Condiments, Sauces, and Processed Foods
| Application | Recommended Level (g/kg) | Recommended Grade | Formulation Notes |
|---|---|---|---|
| Sauces and dressings | 0.2–0.4 | GSG 80% | Salt, vinegar, and umami compounds provide masking; stevioside is stable through pasteurization; GSG 80% is the standard specification |
| Jams and fruit preserves | 0.2–0.3 | Reb A 97% or GSG 80% | High-acid, high-flavor matrix; thermal processing at jam temperatures (≥85°C) does not degrade stevioside |
| Pickled and fermented products | 0.09–0.20 | GSG 80% | Low use levels required; complex salt-acid environment masks bitterness |
| Processed meat products | 0.09–0.15 | GSG 80% | Low addition; savory matrix effectively masks any stevia character |
Dietary Supplements and Nutraceuticals
| Application | Recommended Level (g/kg) | Recommended Grade | Formulation Notes |
|---|---|---|---|
| Protein powders and meal replacements | 0.20–0.30 | Reb A 97% or Reb M 95% | Protein matrices can amplify bitterness; Reb A or Reb M preferred; vanilla and chocolate flavors improve palatability |
| Chewable tablets and gummies | 0.20–0.27 | Reb A 97% | Direct mouthfeel contact; Reb A minimum; polyols (sorbitol, xylitol) complement sweetness profile and provide bulk |
| Oral liquid supplements and syrups | 0.20–0.25 | Reb A 97% or Reb M 95% | Simple aqueous matrix with no masking — Reb M 95% recommended for pediatric formulations where taste acceptance directly affects compliance |
Frequently Asked Questions
What is the difference between stevia and stevioside?
Stevia refers to the plant (Stevia rebaudiana Bertoni) or loosely processed leaf material. Stevioside is a specific purified compound extracted from the stevia leaf — one member of the steviol glycoside family the plant produces. The leaf contains over 40 identified steviol glycosides; stevioside is the most abundant, typically 5–10% of leaf dry weight. Commercial stevia extracts are standardized by total steviol glycoside content and the proportion of specific glycosides such as stevioside or rebaudioside A.
What are the main steviol glycosides in stevia leaf?
The four major glycosides in a standard stevia leaf are stevioside (5–10% dry weight), rebaudioside A (2–4%), rebaudioside C (1–2%), and dulcoside A (0.3–0.5%). Minor glycosides present in trace amounts include rebaudioside B, D, E, F, M, and rubusoside. Rebaudioside M has attracted commercial interest for its superior sensory profile — sweetness closest to sucrose with minimal aftertaste — despite its very low natural concentration in the leaf.
Is stevioside safe and does it have regulatory approval?
Yes. The US FDA recognizes high-purity steviol glycosides, including stevioside, as Generally Recognized as Safe (GRAS). The European Food Safety Authority (EFSA) has set an acceptable daily intake of 4 mg/kg body weight expressed as steviol equivalents. China’s GB 2760 food additive standard also approves steviol glycosides across a wide range of food categories. Stevioside is metabolized in the gut to steviol, which is then excreted without accumulation. This clean metabolic pathway, supported by extensive toxicological review, underpins its regulatory acceptance across major global markets.
When should a formulator choose stevioside over rebaudioside A?
Stevioside (GSG 80%) is the better specification for high-volume applications where cost efficiency is the primary driver and the matrix can manage its bitter aftertaste — carbonated beverages, baked goods, dairy products, condiments, and industrial food processing. Rebaudioside A 97% is preferred where a cleaner sensory profile is required and the product cannot absorb the bitterness through flavor complexity or masking agents. The decision is a cost-versus-sensory trade-off; both compounds carry the same GRAS regulatory status.
What is the molecular formula of rebaudioside M and how does it differ from stevioside?
Rebaudioside M has the molecular formula C₅₆H₉₀O₃₃ with a molecular weight of 1291.30 g/mol (CAS No. 1220616-44-3). Stevioside, by comparison, is C₃₈H₆₀O₁₈ (MW 804.87 g/mol). The key structural difference is at the C-19 position: stevioside carries only a single glucose unit there, while Reb M carries a trisaccharide chain — the same extension seen at C-13. This additional sugar substitution at both positions is what produces Reb M’s markedly cleaner, sucrose-like taste with no licorice aftertaste, distinguishing it from all other major commercial steviol glycosides.
References
[1] Orellana-Paucar, A.M. Steviol Glycosides from Stevia rebaudiana: An Updated Overview of Their Sweetening Activity, Pharmacological Properties, and Safety Aspects. Molecules, 28(3), 1258 (2023). https://doi.org/10.3390/molecules28031258
[2] Okonkwo, C.E. et al. A review on rebaudioside M: The next generation steviol glycoside and noncaloric sweetener. Journal of Food Science, 89(11), 6946–6965 (2024). https://doi.org/10.1111/1750-3841.17401
[3] Khilar, S. et al. An Insight into attributes of Stevia rebaudiana Bertoni: Recent advances in extraction techniques, phytochemistry, food applications and health benefits. Journal of Agriculture and Food Research, 10, 100458 (2022). https://doi.org/10.1016/j.jafr.2022.100458
[4] Ashwell, M. Stevia, Nature’s Zero-Calorie Sustainable Sweetener: A New Player in the Fight Against Obesity. Nutrition Today, 50(3), 129–134 (2015). https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4890837/
[5] Wong, X.J. et al. Discovery of Novel Minor Steviol Glycoside from the Stevia rebaudiana: Structural Characterization and Proposed Biosynthetic Pathway of Rebaudioside D17. Biomolecules, 16(1), 146 (2026). https://doi.org/10.3390/biom16010146
