Recent advancements in natural colorants and their application as coloring in food and in intelligent food packaging

•Dyes are essential in the development of many foods.•Natural colorants allow the substitution of potentially harmful synthetic dyes.•The addition of natural colorants to food permits obtaining fortified products.•Food freshness can be monitored using natural colorants in smart packaging.•The interaction between food/ packaging and natural dyes needs to be further studied. Colorants are widely employed in the food industry as an essential ingredient in many products since color is one of the most valued attributes by consumers. Furthermore, the utilization of colorants is currently being extended to the food packaging technologies. The objective of this review was to compile recent information about the main families of natural coloring compounds, and to describe their real implications in food coloring. In addition, their technological use in different food systems (namely, bakery products, beverages, meat and meat products, and dairy products) and their utilization in intelligent packaging to monitor the freshness of foodstuffs with the aim of extending food shelf life and improving food properties was discussed. The potential of using natural colorant in different food to improve their color has been demonstrated, although color stability is still a challenging task. More interestingly, the application of intelligent colorimetric indicators to exhibit color changes with variations in pH can enable real-time monitoring of food quality.