Foodwatch with Catherine Saxelby

Stevia to the rescue in the noncaloric beverage business

Catherine Saxelby

Zero-calorie sweetener, stevia (Stevia rebaudiana) hit the headlines in the Wall Street Journal in December 2008 with the announcement that the FDA were approving two rebiana-based sweeteners (from rebaudioside A, a highly purified extract of stevia) as being safe for use as a general purpose sweetener in foods and beverages. Australia’s food regulator, FSANZ, had granted approval earlier in 2008.

Cargill is marketing its rebiana-based sweetener Truvia with Coca-Cola; Merisant is working with PepsiCo with their version, Purevia. Both have developed non-nutritive tabletop sweeteners from it.

In what they expect to be the first of many new low- and zero-calorie beverages sweetened with Truvia, Coca Cola has launched a reduced-calorie version of Sprite, called Sprite Green, in the US. Odwalla, also owned by Coke, has added two new reduced-calorie juice drinks to its product line – Mojito Mambo and Pomegranate Strawberry. Apparently not all flavours taste good sweetened with stevia. Citrus flavours taste the best – so we may not see Coke Zero with stevia.

Rebaudioside A – stevia extract

Not to be outdone, Pepsi has three flavors of a stevia-sweetened zero-calorie SoBe Lifewater in Fuji Apple & Pear, Black and Blue Berry, and Yumberry Pomegranate with added vitamins as well. They’ve also just brought out an orange-juice drink called Trop50 with 50% less sugar and calories and the juice of freshly squeezed oranges.

Why the interest in stevia? It’s all part of a move away from aspartame (Equal, Nutrasweet) and acesulphame K towards more ‘natural’ substitutes for sugar for diet drinks. Despite being cleared twice by food authorities, aspartame has been plagued by persistent internet rumours linking it to brain cancer and Alzheimer’s that refuse to go away. Trop50, for example, replaces Tropicana’s previous Light ‘n Healthy orange juice beverage that was made with an artificial sweetener.

Stevia and blood glucose Stevioside does not appear to affect blood glucose levels, good news for those with diabetes. The human body does not metabolise the sweet glycosides and they pass through and are eliminated, so the body does not obtain any kilojoules/calories. You’ll see it sold as a white powder, a liquid extract or as tablets for tea or coffee. It has a slight liquorice flavour. It works well in beverages or yoghurts but not in biscuits or muffins as it can’t duplicate sugar’s ability to add bulk and contribute to the golden-brown colour of baked goods.

So far, so good. If you’re after a non-kilojoule sweetener that’s more ‘natural’, stevia hits the spot. It will be interesting to see how well its safety remains over time and how consumers take to the taste of these new drinks.

Background on stevia Native to South America, the leaves of this semi-tropical shrub are around 30 times sweeter than cane sugar but without the kilojoules/calories. As a herb, the leaves can be used fresh or dried – less than 2 tablespoons of crushed dried leaves can replace a cup of sugar, although it’s hard to be specific as actual sweetness can vary. You can buy stevia leaf powder online from specialty spice merchants such as Herbies Spices (www.herbies.com.au). Ian Hemphill says ‘use sparingly as there is a bitter aftertaste if too much is added to food.’

Catherine Saxelby is an accredited dietitian and nutritionist and runs the Foodwatch Nutrition Centre. For more information on stevia and healthy eating, visit www.foodwatch.com.au.