Sunday, September 20, 2009

Stevia is Going Mainstream

Several years ago sister-in-law Tonee told me about Stevia, and said it was a great natural, sugar-free sweetener. I thought it had a strange aftertaste but the following year I bought some stevia (stevia rubaudia) seeds, and they were easy to grow. The herb was less than satisfactory as a sweetener. While I could taste some sweetness chewing on the stem, the leaves gave mostly a planty flavor.  After this I used to joke that stevia was not a sugar substitute, that it was a saccharine substitute. At right is a stevia plant.

Well, the organic food movement marched on, and big food companies are going to introduce stevia-based products for the mass market. At left is a prototype Sprite Green bottle with Stevia based sweetener.

Rather than the crude stevia extract, they are taking the best tasting fraction of the plant, and with modern plant hybridization (not gene splicing-- at least yet,) the flavor is much better.

It turns out that there are seven sweet components in the stevia extract, and the best tasting of them is called Rebaudioside A. All of these are glycosides of  a terpene alcohol called steviol. The components are shown on the graph at left which is from They vary in the modifications. Rebaudioside A has three pendant glucoses. Its structure is at the bottom. It is a larger and more complex sweetener than any of the current synthetic sweeteners, and happily it is not chlorinated.

Rebaudioside A production is being ramped up by some big name food companies including Coke and Cargill, Pepsi and Merisant, who makes Equal (aspartame). Botanists have developed strains that make 4% rebaudioside A on total plant weight, which will help keep costs down, and I am sure better varieties are coming. The new food products will all be based on plant extract rather than synthetics.

Early on there were controversy about whether the base terpene, steviol, caused liver damage. It seems that this has been disproven, and several companies are claiming GRAS status for Stevia extract. Stevia extract has been an FDA food additive for a while. GRAS status means that it is "generally regarded as safe", and a chemical on this list receives the broadest acceptance in foods.

More: Yes this is my second sweetener story in one weekend. For another sugar fix see my posting on non-fermentable sugars. This reminds me of the movie we saw yesterday The Informant! which was about food additives. The link will take you to my review.