Newly discovered plant pigments could hold food industry promise
The discovery of a new class of natural colours could lead to more vibrant and stable colourings for foods and beverages. Is this the breakthrough the industry has been waiting for?
Anthocyanins are used widely in the food industry, and until now, have been thought of as the main pigments of plants, providing colour to flowers, fruit, and foliage and helping protect against environmental stresses. However, researchers at the New Zealand Plant and Food Research Institute claim to have discovered a new class of plant pigment, which they have dubbed “auronidins”.
The researchers identified the colouring compounds in liverworts, which are thought to be among the closest living relatives to the world’s first land plants – and are known for their ability to survive in extremely harsh conditions. Auronidins are flavonoids with similar colours to anthocyanins, but different chemistry, including strong fluorescence, they wrote in a paper published in Proceedings of the National Academy of Sciences (PNAS).
Like anthocyanins, auronidins tend to be red within plant cells, but in solution, they are able to produce a broader range of colours, from yellow to red and orange and even purple, depending on acidity. Anthocyanins tend toward a narrower range of red-spectrum colours in the conditions typical of foods.
The discovery could lead scientists to rethink the evolution of plant pigments, and also open new possibilities for colouring foods and drinks. If auronidins are able to be used in this way, the New Zealand researchers’ work in understanding how plants make the pigments is likely to be useful in producing them at a commercial scale.
Companies that already have a strong presence in the anthocyanin space, such as DDW, Sensient Food Colors and Naturex (now part of Givaudan), are likely to have a particular interest in more stable, vibrant, plant-derived colourings, but all colour houses are on the lookout for ways to extend their natural colours toolbox.
According to Mintel data, global use of natural colours overtook synthetic in value terms in 2011, and more than 90% of new European product launches have been naturally coloured since 2012. Despite this overwhelming uptake of natural pigments, challenges still remain – among them the very vibrancy and stability issues that auronidins promise to address. Watch this space