31
May

Steviol Glycosides

The stevia plant has enormous sweetening power. The question is what makes stevia sweet? The answer to this question is that the sweet taste comes from naturally occurring compounds within the stevia plant, scientifically called steviol glycosides.

What are steviol glycosides?

Steviol glycosides are the collective name of the sweet substances found naturally in the plant Stevia rebaudiana commonly called stevia.

• There are about forty different steviol glycosides.

• Twelve of them have been approved as sweeteners in the EU.

• Two of these twelve are mainly encountered in practice (Reb A and Reb M)

The steviol glycosides listed below differ in their molecular structure, their sweetening power and their taste.

• Stevioside

• Steviolbioside

• Rubusoside

• Dulcoside A

• Rebaudioside A

• Rebaudioside B

• Rebaudioside C

• Rebaudioside D

• Rebaudioside E

• Rebaudioside F

Rebaudiana A (Reb A) is found in a smaller proportion of stevia leaves (2–4%). Reb A is the most commonly used steviol glycoside in food and beverages. Compared with stevioside which is most commonly found in stevia leaves (5-10%), it has a much less bitter off-taste and much less of an aftertaste of liquorice.

Rebaudiana M (Reb M) has no bitterness and no liquorice-like aftertaste at all. The taste profile of Reb M is almost identical to sugar. This makes Reb M an excellent substitute sweetener for sugar. The proportion of Reb M in stevia leaves is tiny (< 0.1%). That’s why Reb M is much more expensive than Reb. 

What makes steviol glycosides good as sweeteners?

There are two reasons why steviol glycosides are excellent sweeteners. First and foremost, they supply zero calories and do not affect blood sugar levels.

The second reason is that steviol glycosides are extracted from stevia in much the same way that sugar is extracted from sugar beets and canes. Consequently, many consumers see them as a more natural alternative to synthetically produced sweeteners such as aspartame, acesulfame K and sucralose.

Extraction of steviol glycosides

In order for stevia leaf extracts to be used in food, these extracts must strictly adhere to established specifications of identification and purity established by national and global food safety authorities.

Stevia extracts are removed from the leaves of the stevia plant by traditional water/alcohol extraction methods which do not alter the composition of the plant’s sweet compounds.

The process involves steeping the dried leaves of the stevia plant in water, filtering and separating the liquid from the leaves and stems, and further purifying the remaining plant extract with either water or food grade alcohol.

Stevia extracts are exactly the same compound outside the leaf as they are found in the leaf. The goal of this process is to extract and purify the natural substances (steviol glycosides) from the leaves of the plant. The result is a white natural substance which contains at least 95 % steviol glycoside.

Are steviol glycosides natural?

Steviol glycosides are naturally found in stevia plants, and they are extracted in a way that is similar to how sugar is extracted from sugar beets and canes. However, according to EU legislation, steviol glycosides can not be referred to as natural. However, it is OK to say that steviol glycosides are of natural origin.

 Bottom Line

Stevia is a magical plant that offers sweetness with fewer calories and does not show any side effects after consumption on human health. They are thermostable even at higher temperatures, making them suitable for use in cooked foods. Stevia cultivation and production would further help those who have to restrict carbohydrate intake in their diet, to enjoy the sweet taste with minimal or no-calories.

References

International Stevia Council

Disclaimer

Onder Food does not offer personal health or medical advice, diagnosis, or treatment. No content (any medical information) on this site is not intended as a substitute for informed medical advice and you should not take any action before consulting with a healthcare professional.