The food and cosmetics industries have few solutions when they are looking for a water-soluble yellow colorant. One of the most widely employed is a synthetic pigment, tartrazine (E 102), which is suspected of causing asthma and urticaria. Tartrazine is banned in Norway and Austria.â
Last year the UKs Co-op chain banned a raft of food colours, along with tartrazine, due to health concerns.
Now France's Institute for Agronomy Research (INRA) said its scientists studied the natural yellow pigment, POP (phloridzine oxidation product), in collaboration with cider company Val de Vire.
POP has antioxidant properties and is obtained from apples. It can be used in both the food and cosmetic industries. The structure of POP, and how it is obtained, have been patented by INRA and Val de Vire.
Phloridzine is a polyphenol specific to apples. When apples are pressed to obtain juice, phloridzine, oxygen and polyphenoloxidase enzyme combine to form POP, INRA stated in a press release.
INRA researchers claim to have worked out for the first time POP'sâ full structure and the three-stage mechanism by which it is formed.
The production of POP is currently under development. The natural colourant will be useful in foods such as syrups and confectionery creams among others. It could also be used as a colourant for cosmetics, they stated.
Phloridzine oxidation products are known to be partially responsible for the yellow colour of apple juice which remains stable and resistant to the majority of food production processes.
â The POP pigment, which has been purified, produces a brilliant yellow colour with two nuances depending on the acidity of the medium. It is yellow for products with an acidity of less than pH 5 and orange for products with a pH 6, without affecting the luminosity of the original product.â
The spectral properties of POP pigment are stable at between pH 3-5, a level that corresponds to the majority of food and drink products.
Since it is freely soluble in water, POP can be incorporated easily in water-based foods. In addition, products coloured with POP do not stain plastic packaging, unlike those coloured with hydrophobic carotenoid pigments, the scientists stated.
The polyphenol structure of POP pigment gives it antioxidant potential. Synthetic colorants with an azo structure, such as tartrazine, are known to be pro-oxidants.
The scientists are now working to better characterise the behaviour of the colorant in a food product and its behaviour temperature, light stability and other processing parameters. The researchers are also testing the synthesis of certain derivatives of the pigment for cosmetic applications.â
They are also studying how to efficiently produce POP in large quantities.