The trend toward natural colours for foods, drinks and sweets is here to stay – but raises huge technical challenges, according to Steve Tolliday, principal product technologist at Nestlé’s Product and Technology Centre in York, UK.
The trend for natural colours was given a major boost in the European Union in 2010 when a warning label was required to flag the presence of six commonly used artificial colours – known as the ‘Southampton Six’ – after a study from the UK’s University of Southampton claimed their consumption was linked to hyperactivity in some children.
“At Nestlé, we start with what the consumer wants,” said Tolliday at the recent HIE conference in Frankfurt, Germany. “…There is no way back for consumers. Everything now is going to be natural colours in one way or another.”
He highlighted a range of potential challenges for food manufacturers looking to switch out artificial colours, including reduced light and heat stability of many natural alternatives; changes in the volume of colour affecting product recipes; changes in the necessary storage conditions; effects on product pH; increased cost; and consumer acceptability of the colour itself.
However, manufacturers should not be too precious about matching natural alternatives exactly to an existing artificial colour, he said.
“In the end it is the consumer who decides whether a colour is acceptable for that product…But there is research that the consumer doesn’t expect the colour to be 100% the same.”
Tolliday said some natural colours – particularly those sourced from vegetables like pumpkin, carrots or beets – can also have a strong flavour or odour, affecting consumer acceptability. Therefore, it is important to understand how people consume a product before reformulating.
“Depending on the product and concentration we can get comments from consumers, especially when colours are sourced from vegetables,” he said. “…In panned sweets the colour is concentrated in the outer layer of the product.”
For panned confectionery, such as Smarties for example, many children like to lick the colour off the sweet, or use the colour on their lips to imitate lipstick, thereby increasing the chance that they may taste a bitter, vegetable-like flavour unless it is taken into account when choosing which natural colour to use.
Natural colours generally have reduced light stability, Tolliday added, so cutting out artificial colours may mean that manufacturers can no longer use clear packaging.
“We have to spend a lot of time thinking about packaging. You want your consumer to be able to see your product on the shelf, so hiding it in a bag means you have then got to use the artwork to illustrate what’s inside,” he said.
However, there have been advances over the past few years in what is possible for new formulations. Boundaries have been pushed in terms of heat stability, and new colour sources have been identified and developed.
Over the next few years, Tolliday says he expects more discussion about sustainable sourcing of natural colours, as well as interest from other global markets.