Speaking at a conference at Leatherhead Food Research, Dr. Alfrun Erkner from the Nestlé Research Centre in Switzerland said:“People want a tasty, low calorie yoghurt drink that fills them up. From a development perspective this is challenging, but marketing teams want it anyway.”
Erkner told industry players at Dietary Fibre 2010 that product formulation challenges coupled with the EU health claims regulation landscape meant that food producers needed to be increasingly careful about satiety claims: “From a consumer viewpoint, perhaps the best we might be able to say is that such products make you feel a little less hungry for a certain time.”
Fibre and satiety
The link between fibre consumption and satiety is well-grounded. A 2001 study by Howarth et al. in Nutrition Reviews examined reviewed studies and concluded that all those where participants had consumed food according to normal preference showed that an additional 14g of fibre daily resulted in 10 per cent less energy intake.
But Erkner pointed to general difficulties in formulating products with an increased fibre content without adversely affecting taste and desirability amongst consumers, meaning that companies face a tricky balancing act between health and saleability.
Despite the obvious importance of different fibres as a means of increasing the satiating effect of foods, she added: “Fibre cannot act on its own for satiation and satiety – at least not in foods and drinks that consumers would like.”
She also addressed a related marketing problem regarding negative public perceptions of fibre-rich foods.“It’s a particular problem we’ve discussed at Nestlé – consumers want these kind of healthy products but don’t really want to hear about them.”
As background to Nestlé’s recent research regarding the potential development of an high-fibre yoghurt drink, Erkner cited a paper the firm had sponsored by Slavin and Green in 2007. Published in Nutrition Bulletin, it analysed studies looking into satiety effects of high-fibre diets, whole foods and isolated fibres added to foods.
The results showed that foods containing viscous fibres such as psyillium, pectin and guar gum had the strongest satiating effects.“The key question is how you get this fibre into low-calorie food such as yoghurts,” Erkner said.
“We wanted a drinking yoghurt with a marked satiating effect. We increased the fibre content, which is not easy with viscosifying fibres, because you face the potential problem of adversely affecting taste – producing something that is too viscous and fruit-laden.”
She revealed that Nestlé had developed a fibre-rich drinking yoghurt that carried 1.8g of fibre in a 160ml serving, which it then tested in a randomised cross-over trial against other iso-caloric foods. These were a regular yoghurt, a banana, a cracker portion and a water serving that acted as an iso-volumetric, zero-calorie control.
Erkner said the research showed that after 60 minutes the high-fibre drinking yoghurt returned higher combined satiety scores than all the other products on a 100-point satiety scale. “Overall there was a clear trend for the high-fibre yogurt to be the most satiating,” she said.