Prunus spp. fruits as practical natural colouring agents in food

Fruits and vegetables are among the most important phytochemical sources worldwide, which can also provide an anticipated food colour. The sensory perception of the food is directly linked to its colour. Consumers have a specific expectation for the colour of food i.e. desired and vivid ones. Thus, colour additives, both natural and synthetic, are so important to the food industry. Colour additives are able to enhance the sensory attributes lost during processing, and to expand product variety. However, studies report a link between synthetic colours and some health disorders. That is why serious attention is paid to natural dyes. In this context, Prunus fruits present an excellent alternative source of natural compounds that enable the production of a wide range of colouring molecules, such as anthocyanins, carotenoids and chlorophylls. Moreover, in addition to their ability to colour, they also contribute by increasing food’s bioactive qualities. Carotenoids are the pigments that give the yellow and orange colour to the pulp and skin of apricots and other Prunus fruits. Along with them, flavonoids, anthocyanins (purple, blue colours), etc. are also found in prunes, for example. Still, whether the fruit can be used as a reliable source of food colouring is an open question worth answering. Therefore, more research is currently needed to better understand the behaviour of natural compounds during the extraction processes and further incorporation into food matrices. In this regard, scientists add fruits directly in the food in order to avoid extraction and potential loss of bioactive compounds, i.e. natural dyes. Regulation approvals should always be considered as well and it has to be noted that different legislation applies to different countries. In view of the sustainable food cycle provision and the seek for more value added ingredients, natural dyes ought to be taken into account with priority.