Stevia, a natural sweetener derived from the leaves of the Stevia rebaudiana plant, has revolutionized sugar reduction in food and beverages. Its sweetening compounds, steviol glycosides, range in purity and composition, offering distinct sweetness profiles, taste characteristics, and applications.

The most notable steviol glycosides include Rebaudioside A (Reb A), Rebaudioside M (Reb M), Rebaudioside D (Reb D), and Stevioside, each with unique functionalities tailored for specific formulations.

This blog provides a comprehensive exploration of stevia grades, focusing on Reb A (60, 80, 97, 99), Reb D, Reb M, and Stevioside, highlighting their technical specifications and diverse applications.

Understanding Steviol Glycosides

Steviol glycosides are calorie-free, natural compounds that are 150–300 times sweeter than sucrose. These compounds vary in molecular structure, which directly affects sweetness intensity, bitterness, solubility, and thermal stability.

Primary Steviol Glycosides:

• Rebaudioside A (Reb A): High sweetness intensity with varying purity levels.
• Rebaudioside M (Reb M): Offers the closest sugar-like taste with minimal bitterness.
• Rebaudioside D (Reb D): A cleaner, milder sweetener suitable for blends.
• Stevioside: Traditionally used but has a stronger aftertaste.

Stevia Grades: Purity and Technical Features

The performance of stevia in formulations depends on the grade, which varies in glycoside content and purity.

Reb A Grades

1. Stevioside:
   • Purity: Varies.
   • Taste: Strong sweetness with a characteristic bitter aftertaste.
   • Applications: High-heat applications like baking and caramelizing.
2. Reb A 60:
   • Purity: 60% Reb A.
   • Taste: Noticeable bitterness, suitable for blending with other sweeteners.
   • Applications: Cost-efficient sugar-free drinks and confectioneries.
3. Reb A 80:
   • Purity: 80% Reb A.
   • Taste: Moderate sweetness, less bitter than Reb A 60.
   • Applications: Sauces, mid-range beverages, and baked goods.
4. Reb A 97:
   • Purity: 97% Reb A.
   • Taste: Clean sweetness with minimal aftertaste.
   • Applications: Premium beverages and table-top sweeteners.
5. Reb A 99:
   • Purity: 99% Reb A.
   • Taste: Nearly sugar-like sweetness with negligible bitterness.
   • Applications: Dairy formulations, clean-label products.

Advanced Glycosides

5. Reb D:
   • Purity: ≥95%.
   • Taste: Very Low bitterness and high sweetness intensity.
   • Applications: Used in blends to mask aftertaste in confections and beverages.
6. Reb M:
   • Purity: ≥95%.
   • Taste: Closest to sucrose, with no detectable bitterness. Very high sweetness.
   • Applications: Premium sugar replacements in dairy, beverages, and functional foods.

Applications of Steviol glycosides Grades

Beverages

• Reb A 97/99 and Reb M are ideal for carbonated drinks, flavored waters, and energy beverages due to their clean sweetness profiles.
• Reb D works well in complex beverages like teas, masking herbal or acidic notes.

Baking

• Reb A 80 and Stevioside are widely used in baked goods for their heat stability.
• Reb M enhances the sugar-like sweetness in premium baked products, reducing aftertaste.

Dairy Products

• Reb M provides a sugar-like profile in yogurts, ice creams, and milk alternatives.
• Reb A 99 is used for low-calorie dairy formulations, maintaining a clean-label appeal.

Confectionery and Table-Top Sweeteners

• Reb A 97/99 and Reb M dominate table-top sweeteners, offering consumers an excellent sugar alternative.
• Stevioside and Reb A 60 are cost-effective for hard candies and chewing gums.

Technical Considerations of Steviol Glycosides for Formulators

1. Solubility and Stability

• Reb M and Reb D are highly soluble, making them suitable for liquid formulations.
• Stevioside excels in stability under high temperatures and acidic conditions, ideal for baking.

2. Blending with Other Sweeteners

• Reb A 60 and Reb A 80 are often blended with erythritol, xylitol, or maltitol to mitigate bitterness and improve texture.
• Reb M pairs well with erythritol for sugar-like taste without calorie addition.

3. Flavor Masking

• Advanced grades like Reb M and Reb D minimize aftertaste and can mask herbal or bitter notes in beverages and dairy products.

Conclusion

The wide range of stevia grades allows formulators to tailor sweetness profiles for specific applications.

From the clean, sugar-like sweetness of Reb M to the robust stability of Stevioside, stevia offers versatility across industries.

Understanding the technical nuances of each grade empowers manufacturers to create innovative, reduced-calorie products that meet consumer expectations for taste, functionality, and health.