As the saying goes, "We eat first with our eyes". The visual appearance, especially the colour, of a food or beverage product is one of the first things that a consumer will assess, using this information to decide whether a product looks good enough to taste or purchase.
Studies have shown that colour significantly impacts peoples' ability to identify food and beverages, with uncoloured or miscoloured products being identified correctly less frequently than appropriately coloured products. We often associate certain colours in certain foods as an indication that the food has gone off (for example, green bread indicates the presence of mould). A product that has the "wrong" colour may therefore deter consumers from tasting it. In fact, the colour of a food or beverage can exert a dramatic effect on a person's psychological expectation of taste. As such, colour may be the most visual aspect of a food or beverage item and is thus a critical component in new product development.
The addition of colours to foods has been carried out for centuries, dating back as far as the ancient Egyptians. In 1856, William Henry Perkin developed and patented one of the first synthetic dyes, mauveine, which was initially used to dye clothing. While the dye was also approved for use as a food colouring, it was later found to be toxic!
Today, colourings remain a key part of the food and drink industry – according to some estimates, the global food colours market will reach USD 6 billion by 2028.However, as with other food and drink ingredients, consumers are increasingly concerned about the long term health effects of synthetic food colourings, the environmental impact of additives and their production, and ethical issues associated with some food colourings, such as carmine which is derived from crushed insects. At the same time, food producers are increasingly looking to develop products that are eye-catching and distinct from the competition, while retaining their visual properties during storage and on the shelf.
So, how are manufacturers of food colourings responding to these challenges? In order to find the very latest innovations in the field, we reviewed the patent literature to identify recently-published applications relating to food colours and their production.
Some of the major players who have filed patent applications in this sector include Givaudan, Chr Hansen Natural Colours, Oterra, Mars, Japanese company Fancl Corp, Chenguang Biotech Group based in China, and Danish start-up Chromologics. As for the types of technology that patent applicants such as these are focussing on, our search revealed the following key trends:
(1) Improved stability
One of the main challenges for those developing food colours is achieving a colouring agent that remains stable during manufacture of the final food or beverage product, and on the shelf.
Phycocyanin, a natural blue dye derived from spirulina (the cyanobacterium Arthrospira platensis), is of particular interest due to its antioxidant and anti-inflammatory properties. However, phycocyanin is sensitive to pH, temperature and light, leading to discolouration and limiting its use in certain products. Givaudan seeks to solve this problem by combining phycocyanin with certain water-soluble proteins or peptides, such as those derived from potatoes, beans and nuts, as described in international patent application WO2023052343.
Further compositions aimed at stabilizing phycocynanins are the subject of patent applications filed by Chr Hanson Natural Colours (now Oterra). EP3975750 describes a composition in which the phycocyanin is stabilized by polyphenol, which acts as a complexing agent, and an encapsulating agent. A follow-on application EP4072313 focuses on the specific combination of phycocyanin with glycerol and modified starch.
(2) Colours produced by fermentation
The use of fermentation for the production of food colours has several benefits, including the reduced cost of raw materials, ease of scale-up, higher yields and reduced environmental impact compared to synthetic methods, and no seasonal variations as with plant-derived colours.
Numerous companies are taking advantage of these benefits of fermentation. One of these, Danish start-up Chromologics, has filed a family of patent applications (for example EP4176069), directed to a method of preparing an atrorosin food colouring composition from fermentation broth. Atrorosins were discovered in 2019 as a new class of red pigments produced by the filamentous fungus Talaromyces atrotoseus. Atrotosins are said to solve problems associated with existing natural red food colourants such as betanin (Beetroot Red, E162), which has poor temperature stability, and carmine (cochineal, E120), which is extracted from insects making it unsuitable for kosher, halal and vegan foods.
Also aimed at red pigments, patents have been granted to The Technical University of Denmark (DTU) for a new class of natural red azaphilone pigments and their production by the fungus Aspergillus cavernicola (see, for example, granted European patent EP3909954B1). These provide an alternative to the production of pigments using the fungus Monascus, which produces a cocktail of pigments that can vary in its composition, as well as potentially containing mycotoxins.
The purification of phycocyanins produced by fermentation of microalgae is the subject of a series of applications filed by Fermentalg, including European application EP3908121A1. The method of the invention is said to solve the problem of industrial-scale purification of phycocyanins, while avoiding harsh chemicals, reducing residual sugar content and preserving the properties of the colourant.
(3) Meat mimetics
In addition to developing products that have the taste and texture of meat, another challenge for producers of meat mimetics is replicating the colour of meat – not only the colour of raw or cooked meat, but both. Inventions relating to food colourings which undergo a colour change from pink or red to brown upon heating are the subject of a number of recently-filed patent applications.
For example, international patent application WO2023232931 (Givaudan) describes a colouring composition comprising lutein (a carotenoid), ferrous iron and optionally chlorophyll. In addition to providing colour, the composition is said to provide a "meaty" odour and taste, as well as imparting a caramelized taste note upon heating to higher temperatures over a longer period of time, as in cooked meat.
Another example developed by Australian company V2 Foods, and launched under the brand name "RepliHue", is claimed in international patent application WO2021195708. The invention is based on the finding that certain phycobiliproteins, in particular phycoerythrin, provide a similar colour change to that which occurs during cooking of animal meat.
Central to all of these key themes, and the majority of other inventions identified in our patent search, is the focus on natural food colours, as consumers increasingly look towards food products which are clean label and have reduced environmental impact.
What's also clear is that despite centuries of development in food colouring technology, there is no shortage of innovation as companies rise to meet the ongoing challenges presented to them by food manufacturers and consumers alike.
The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.
