History of Stevia
Stevia is a plant native to South America that has been used as a sweetener for hundreds of years. Today, zero-calorie stevia, as high-purity stevia leaf extract, is being used globally to reduce energy and added sugar content in foods and beverages.
WHERE DOES STEVIA COME FROM?
Stevia is a naturally sourced, zero-calorie sweetener that has been used as a natural sugar substitute and flavoring ingredient for hundreds of years. The stevia plant is native to South America and was first consumed there over 200 years ago when the indigenous people used leaves of the plant to sweeten beverages or chewed them for their sweet taste. The plant leaves, often called “sweet herb,” were dried and used to sweeten teas and medicines or simply chewed as a sweet treat.
The stevia plant was first scientifically recorded in 1899 as Eupatorium rebaudianum by Moises Santiago de Bertoni, in Paraguay. In 1905, it was later defined as Stevia rebaudiana, a member of the sunflower (Asteraceae) family.
Stevia, as a plant extract, was first commercially adopted as a sweetener by Japan in the 1970s, where it is still a popular ingredient today. Stevia is cultivated mostly in Paraguay, Kenya, China, and the United States and within many other parts of the world, including Vietnam, Brazil, India, Argentina, and Colombia.
Stevia Definitions
Stevia is the generic term used to refer to different forms of the sweetener, including the whole plant Stevia (S rebaudiana Bertoni) and the leaves where the sweet compounds are found. Stevia extract is a generic name for a preparation made by steeping the leaves of the Stevia plant to extract the sweet compounds from the leaf material.
On the other hand, high-purity stevia leaf extract contains 95% or greater steviol glycosides. Only high-purity stevia extracts meeting this specification are approved by major regulatory agencies, including the Joint Food and Agriculture Organization/World Health Organization (WHO) Expert Committee on Food Additives and Codex Alimentarius (Codex) for use in foods and beverages.
The term “stevia” as used in this article refers to high-purity stevia leaf extract.
Stevia is a sweetener and a natural origin plant extract that has been consumed for over 200 years. However, high-purity stevia leaf extract is now on the market today.
STEVIA’S SWEETNESS
The sweet-tasting components of stevia are called steviol glycosides, which are naturally present in the stevia leaf. There are 11 major steviol glycosides (Figure 1), of which rebaudioside A and stevioside are the most abundant. Figure 2 shows the basic chemical structure of all steviol glycosides. Purified stevia leaf extracts can contain one steviol glycoside or several different glycosides, which can be up to 250 to 300 times sweeter than sucrose
The process of purifying stevia into high-purity stevia leaf extract is similar to how other plant-based ingredients, such as cane sugar or natural vanilla extract, are made through a series of steps beginning with the harvested, raw plant material through to the end product. The process begins by drying the leaves and then steeping them in hot water. Next, the liquid extract is filtered and purified with water or in some cases in combination with food-grade alcohol. If food-grade alcohol is used, it is later removed and no significant amount of alcohol remains in the end product. Other processes may be used in some cases. Further technical details are available in the cited article by Prakash et al.3
The purified steviol glycosides are the same molecules as originally found in the leaf. High-purity stevia leaf extracts (>95% steviol glycosides) are required to meet US and European regulatory approvals and safety standards for foods and beverage use.
PURIFIED STEVIA LEAF EXTRACT
High-purity stevia extract contains 95% or greater steviol glycoside content and is often referred to as stevia, steviol glycosides, stevia extracts, purified stevia leaf extract, high-purity stevia, or rebiana. Only high-purity stevia extracts meeting this specification are approved by major regulatory agencies, including the Joint Food and Agriculture Organization/WHO Expert Committee on Food Additives4 and Codex, for use in foods and beverages. For simplicity, the term “stevia” as used in this article refers to purified steviol glycosides.
Stevia in Your Foods and Drinks
Food scientists continue to explore ways to use stevia-based sweeteners. Proposed uses for high-purity stevia leaf extracts include soft drinks, canned fruit and jams, ice cream and other dairy products, cakes and desserts, and alcoholic beverages.
Stevia Metabolism
The backbone of all steviol glycosides is steviol, to which various glycoside (glucose) groups attach to form the variety of sweet compounds in stevia (Figure 2). Steviol glycosides pass through the upper gastrointestinal tract fully intact. Gut bacteria in the colon hydrolyze steviol glycosides into steviol by snipping off their glucose units. Steviol is then absorbed via the portal vein and primarily metabolized by the liver, forming steviol glucuronide, which is primarily excreted in the urine. Research shows that there is no accumulation of stevia (or any component or by-product of stevia) in the body and that it passes through the body during metabolism. Energy from fermentation of glucose units (usually assessed as 2 kcal/g) is so low that it is minimal, and so, effectively, stevia can be said to provide zero calories.5,6 High-purify stevia leaf extract is not metabolized, so it provides zero calories.
Reference:
