Good carb, bad carb

Talk about dietary fibre 20 years ago and the words bran flakes would spring to mind; 10 years later fibre gurus were talking whole-meal bread, pasta and muesli. Today when nutritionists mention fibre they speak of bad carbs and good carbs.

That is because carbohydrates break down in the body to become sugar -- which gives us energy -- and fibre. But most of those currently used in processed foods are refined carbohydrates that contribute a lot to energy levels but not much in the way of fibre.

However, it seems the Atkins and South Beach diet revolution has initiated a wider questioning of the value of carbohydrates. And while the diet crazes may be waning, consumers are now more aware that, if carbs are to be consumed they should at least be the good ones.

Today, there is a huge array of carbohydrate-based ingredients on the market, ranging from traditional ingredients such as wheat and corn flour, to cassava, tapioca and guar gum to the prebiotic inulins and functional starches sold by the likes of Orafti, National Starch, Cargill and Acatris. But it is the ones with health benefits, such as the ability to release sugar slowly, that have good future prospects.

As Lisbeth Neven, product manager for health ingredients at Acatris, says, in the current market, where consumers are measuring food by their carbs rather than calories, the next trend is the 'slow carb' trend.

Slow Carbs

She's talking about carbohydrates that break down slowly to give a slow release of sugar rather than creating peaks and troughs in blood sugar levels -- a phenomenon commonly expressed and measured in terms of glycaemic index (GI).

Petra de Wit, marketing communication manager at Acatris, believes there is increasing awareness of the role of GI, which is coming to be seen as a more sensible way of reducing sugars and losing weight: "We are predicting a link between the current trend for low carbs and 'slow carbs' or low-GI foods," she says.

Both in the US and here, low-GI starches are now being marketed at food manufacturers for applications that include breads, tortillas, pizza crusts, cookies, muffins, breakfast cereals, nutritional bars and more.

The fibre aspect is important for other health reasons. For example, the majority of starches are digested and absorbed into the body through the small intestine. Those that are high in fibre resist digestion and pass through to the large intestine.

Known as resistant starches, they are starting to have an impact on starch choice. Hi-maize from National Starch, for example, is already being used in products such as a high-fibre white bread, on the market in Sweden, and in breakfast cereals launched by Vogel in the UK.

In the US Cargill plans to produce and market corn- and tapioca-based resistant starches through a process it will sub-license from ingredient company MGPI. Cargill already markets a resistant maltodextrin called ActiStar in Europe.

To help consumers distinguish such high-fibre products, National Starch is now calling for a change in US rules that would allow fibre content to be listed independently of the 'total carbohydrate' declaration listed on packs.

Cancer prevention

Some high fibre ingredients are said to offer prebiotic health benefits. This is because the fibre present in the lower intestine gives the 'friendly' bacteria in the gut literally something to chew on. These bacteria, in turn, help to maintain a healthy digestive system.

There is even research into whether such bacteria can help prevent colon cancer. Orafti for example, which markets chicory inulin and oligofructose for gut health, has been investigating the action of its ingredient Raftilose Synergy 1, combined with probiotic bacteria, against colon cancer.

At the Swiss health ingredients exhibition Vitafoods held in May, the Swiss group DKSH Schweiz (formerly known as SiberHegner Co) unveiled two new products: arabinogalactan, a pH stable prebiotic fibre derived from larch trees, and WGP beta-Glucan, a carbohydrate derived from baker's yeast, which it says can boost the immune system.

Such activity suggests that while the diets may come and go, the awareness that they have created means the switch to healthy carbs could be a trend that is around for much longer.FM