Although the growing demand for natural alternatives is a long-term trend, it went up a notch when warning labels were introduced across Europe on foods containing the synthetic colours implicated in hyperactivity by the now famous Southampton study. The 2007 study, funded by the Food Standards Agency, looked at the effect of six synthetic colours on children.
While the study only looked at a handful of colours, the subsequent publicity has led to far wider reformulation efforts to appeal to consumers looking to avoid anything artificial. And what seems to be happening now is that there is a growing drive across Europe to ditch even natural colour additives and replace them with ingredients that add colour.
These colouring foods, or foodstuffs, don't have e-numbers and do not have to go through the same onerous approvals process as additives in the EU do essentially because they're made from concentrates of things like fruit and veg that people eat already.
Lots of colouring additives are also derived from recognisable food sources, such as curcumin from turmeric, so the status of some colouring foods as ingredients rather than additives can be something of a grey area.
The Natural Food Colours Association (Natcol) uses a working definition that stipulates that colouring foodstuffs should be food processed so as not to 'selectively extract' the pigment. Meanwhile, food additives are defined in EU legislation as 'any substance not normally consumed as a food in itself and not normally used as a characteristic ingredient of food, whether or not it has nutritive value, the intentional addition of which to food for a technological purpose results in it or its by-products becoming directly or indirectly a component of such foods'.
"You might start with a food but if you're extracting an element of it it's more likely to be an additive," says Dominic Watkins, senior associate, litigation, regulatory, for specialist food law firm DWF. "There are plenty of examples of instances where the distinction is blurred."
Colourant road tests
The European Commission (EC) currently has a working group that is 'road testing' the status of various colouring substances with a view to establishing a clearer dividing line later this year. The candidates under scrutiny include orange carrot, black carrot, elderberry, hibiscus, red cabbage, safflower, spirulina, turmeric/curcumin, paprika, pumpkin, beetroot, nettle extract and gardenia concentrates.
However, Watkins is doubtful whether the guidance will arrive on schedule. "Don't hold your breath for things moving swiftly," he warns.
If the EC eventually decides that some colouring foods are additives rather than ingredients, it will no longer be legal to use them to colour food products in the EU until they go through the approvals process to be added to the community list.
So with a frenzy of research and development work underway in this area, what should food manufacturers do? According to Watkins, it seems sensible to "keep doing what you're doing if it makes business sense now", rather than waiting for months or even years to see which side of the line a particular colouring substance ultimately falls on.
And that's pretty much what the industry has been doing, with colouring food ranges being launched or expanded across the board to meet growing demand.
Naturex launched its VegeBrite range at the end of 2011. Lionel Lesegretain, business manager of the natural colours division at Naturex, explains the company's approach: "We have adopted the simplest position: we only offer pure fruit and vegetable concentrates obtained only from physical processes such as centrifugation or filtration. Water is the only solvent extraction that is accepted to manufacture these colouring foodstuffs.
"For example, we do not consider that turmeric oleoresins at 45% can be part of the VegeBrite range. The concentration indicates that this product has been selectively extracted and the solvent used is not water (it's hexane or acetone). For Naturex, this product is a spice extract, and therefore cannot be included in the colouring foodstuffs category."
The Naturex yardstick also excludes other potential candidates, such as spinach and carrot oleoresins, which are extracted using hexane: "VegeBrite offers colouring foodstuffs that are compliant with the most 'clean-label' definition. They do not contain any additives such as emulsifiers (absolutely necessary for the formulation of the naturally oil soluble oleoresins such as turmeric, paprika, carrot or spinach) or stabilisers and are aseptically packed in order to be preservative free."
Range extension
Chr Hansen has also jumped on board by substantially expanding its FruitMax colouring foodstuffs range, which was first launched in 2007. It now offers a broader palette across more applications, with vivid greens, blues and purples for confectionery, for example.
"Of course regulation has played its part, but consumers in general are really driving the conversion," says Peter Thorninger, head of marketing in Chr Hansen's natural colours division. "Natural colours are really booming in emerging markets like Asia and Latin America, while colouring foodstuffs are more important in mature markets such as Europe."
Lesegretain also sees colouring foods as a characteristically European development: "The VegeBrite range particularly benefits from the strong demand from within the European market. E-Color [Naturex's natural colour additive range] is predicted to a have double-digit growth, thanks to our ability to understand our client's needs and to offer innovations that meet the customers' technical constraints worldwide."
There are various technical challenges associated with making a switch to food colourings.
"Because it's a food it's going to be less concentrated so the dosage needs to come up and you'll need to get more technical advice," says Thorninger. "With the synthetic colours you didn't need to think about it because they just worked. Natural colours are more difficult and colouring foodstuffs are even more so."
"It's not a 'one in, one out' substitution," agrees Paul Collins, md of GNT, which has been offering colouring foods in the shape of its Exberry range for decades. "There are always challenges. If it's a soft drink it's likely to be maintaining stability throughout a shelf-life of nine to 12 months in a clear bottle. With a boiled sweet it's the extreme heat that occurs during processing.
"Colouring foods have been progressively developed over the years to answer these challenges. It would be an exaggeration to say that everything is possible but we've progressively been finding solutions driven by market demand."
According to Lesegretain, pH sensitivity means that confectionery, beverages and dairy will continue to be the "easy win" application areas for colouring foods: "All fruit and vegetable concentrates providing red shades contain anthocyanins that are very sensitive to pH. This makes them a perfect ingredient to be included in acidic applications such as beverages and confectionery.
"The beverage, confectionery and dairy sectors are very dynamic at the moment in terms of product development. The group is continually researching new pigment sources. Several fruits and flowers are being studied for their hue properties and their response to pH. Intra-molecular or extra-molecular co-pigmentation can provide another solution to this problem."
Sensient's new Cardea range aims to push the application envelope further by introducing the first colouring foods to be available in both water and oil-soluble versions. "Sensient has incorporated a breakthrough innovation which allows all-natural oil-soluble solutions for the first time," says the company. "This Cardea line is ideal for oil-based colouring products such as chocolate decorations, dressings or glazes. Together with the water soluble versions, they can be also recommended for jellies and high boiled candies, fruit preps, as well as dairy and ice cream products."
Improved stability
The technology behind Cardea uses interactions between ingredients to improve stability while remaining totally natural, according to Sensient: "The Cardea product line contains fruit and vegetable concentrates and extracts such as paprika, lemon, acerola, red beet, apple, carrot, sunflower and spinach. These modules function as natural pigment and natural stabilising ingredients. This allows protection against both oxidation and fading in order to safeguard the intense natural colour shades."
Colouring foods are still a relatively niche market compared with natural colour additives, and there is also a lot of work going on in additives. Take carmine, for example, which is a natural red pigment extracted from beetles. Raw material costs shot through the roof in recent years, leading to a variety of new solutions and alternatives.
For instance, Chr Hansen's award-winning Red Strawberry Fragaria 100 WS is a liquid carmine colour that enables manufacturers to reduce pigment concentration by 1020% compared to standard carmine. Meanwhile, LycoRed has just launched a vegetarian carmine substitute based on tomato lycopene for the surimi (mock crab) market. LycoRed's tomato lycopene formulations are freely blendable with other colours such as paprika to allow manufacturers to tailor the red colour to suit local preferences.
Ultimately, it's all about consumer choice. "Colouring food should be providing an honest, genuine alternative to additives. It should be different or we're not offering consumers a real choice. That's why we think colouring foods will remain part of the portfolio going forwards," says GNT's Collins.